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  • 151.
    Garoff, Maria
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Johansson, Elias
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Ahlqvist, Jan
    Umeå University, Faculty of Medicine, Department of Odontology.
    Arnerlöv, Conny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Levring Jäghagen, Eva
    Umeå University, Faculty of Medicine, Department of Odontology.
    Wester, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Calcium quantity in carotid plaques: detection in panoramic radiographs and association with degree of stenosis2015In: Oral surgery, oral medicine, oral pathology and oral radiology, ISSN 2212-4403, E-ISSN 2212-4411, Vol. 120, no 2, p. 269-274Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To determine calcium volume in extirpated carotid plaques, analyze correlations between calcium volume and degree of stenosis, and analyze whether calcium volume influences the possibility of detecting stenosis in panoramic radiographs.

    STUDY DESIGN: Ninety-seven consecutive patients with ultrasonography-verified carotid stenosis were examined with panoramic radiography before surgery. Extirpated carotid plaques (n = 103) were analyzed for calcium volume by cone beam computed tomography (CBCT). Panoramic radiographs were analyzed for carotid calcifications.

    RESULTS: The median calcium volume was 45 mm(3) (first quartile subtracted from the third quartile [IQR], 14-98 mm(3)). We observed no correlation between calcium volume and degree of stenosis. Seventy-eight stenoses were situated within the region included in the panoramic radiographs, and their volumes ranged from 0 to 509 mm(3). Of these, 99% revealed carotid calcifications on panoramic radiographs.

    CONCLUSIONS: We found no association between calcium volume and degree of carotid stenosis. Calcium volume did not influence the possibility of detecting carotid calcifications in panoramic radiographs.

  • 152.
    Garoff, Maria
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Johansson, Elias
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience, Clinical Neuroscience.
    Ahlqvist, Jan
    Umeå University, Faculty of Medicine, Department of Odontology.
    Levring Jäghagen, Eva
    Umeå University, Faculty of Medicine, Department of Odontology.
    Arnerlöv, Conny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Wester, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Detection of calcifications in panoramic radiographs in patients with carotid stenoses ≥50%2014In: Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics, ISSN 1079-2104, E-ISSN 1528-395X, Vol. 117, no 3, p. 385-391Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: Carotid stenoses ≥50% are associated with increased risk for stroke that can be reduced by prophylactic carotid endarterectomy (CEA). Calcifications in arteries can be detected in panoramic radiographs (PRs). In a cross-sectional study, we analyzed (1) extirpated plaques for calcification, (2) how often PRs disclosed calcified plaques, (3) how often patients with stenoses ≥50% presented calcifications in PRs, and (4) the additional value of frontal radiographs (FRs).

    STUDY DESIGN: Patients (n = 100) with carotid stenosis ≥50% were examined with PRs and FRs before CEA. Extirpated carotid plaques were radiographically examined (n = 101).

    RESULTS: It was found that 100 of 101 (99%) extirpated plaques were calcified, of which 75 of 100 (75%) were detected in PRs; 84 of 100 (84%) patients presented carotid calcifications in the PRs, in 9.5% contralateral to the stenosis ≥50%.

    CONCLUSIONS: Carotid calcifications are seen in PRs in 84% of patients with carotid stenosis ≥50%, independent of gender. FRs do not contribute significantly to this identification.

  • 153. Giannobile, William V.
    et al.
    Berglundh, Tord
    Al-Nawas, Bilal
    Araujo, Mauricio
    Bartold, P. Mark
    Bouchard, Philippe
    Chapple, Iain
    Gruber, Reinhard
    Lundberg, Pernilla
    Umeå University, Faculty of Medicine, Department of Odontology.
    Sculean, Anton
    Lang, Niklaus P.
    Lyngstadaas, Petter
    Kebschull, Moritz
    Galindo-Moreno, Pablo
    Schwartz, Zvi
    Shapira, Lior
    Stavropoulos, Andreas
    Reseland, Janne
    Biological factors involved in alveolar bone regeneration Consensus report of Working Group 1 of the 15(th) European Workshop on Periodontology on Bone Regeneration2019In: Journal of Clinical Periodontology, ISSN 0303-6979, E-ISSN 1600-051X, Vol. 46, p. 6-11Article in journal (Refereed)
    Abstract [en]

    Background and Aims: To describe the biology of alveolar bone regeneration.

    Material and Methods: Four comprehensive reviews were performed on (a) mesenchymal cells and differentiation factors leading to bone formation; (b) the critical interplay between bone resorbing and formative cells; (c) the role of osteoimmunology in the formation and maintenance of alveolar bone; and (d) the self‐regenerative capacity following bone injury or tooth extraction were prepared prior to the workshop.

    Results and Conclusions: This summary information adds to the fuller understanding of the alveolar bone regenerative response with implications to reconstructive procedures for patient oral rehabilitation. The group collectively formulated and addressed critical questions based on each of the reviews in this consensus report to advance the field. The report concludes with identified areas of future research.

  • 154. Glibert, Maarten
    et al.
    Östman, Sara
    Umeå University, Faculty of Medicine, Department of Odontology.
    De Bruyn, Hugo
    Östman, Pär-Olov
    The Influence of Initial Hard and Soft Tissue Dimensions on Initial Crestal Bone Loss of Immediately Loaded Dental Implants2018In: The international journal of periodontics & restorative dentistry, ISSN 0198-7569, E-ISSN 1945-3388, Vol. 38, no 6, p. 873-878Article in journal (Refereed)
    Abstract [en]

    The aim of this case-control study was to evaluate the influence of soft tissue thickness at implant placement (thin [< 3 mm] vs thick [>= 3 mm]) and bone volume (abundant vs limited) on initial crestal bone remodeling of immediate postextraction and delayed (healed site) implants in immediate loading situations. A total of 67 patients with 133 implants could be evaluated, of which 77 were placed immediately after extraction and 56 in healed ridges. If sufficient bone volume is present and primary stability is achieved, immediate loading of the implant yields good clinical and radiographic outcomes, yet implants placed in healed ridges with thin soft tissues are more prone to initial crestal bone loss.

  • 155.
    Gonzales, Jose Roberto
    et al.
    Department of Periodontology, Justus-Liebig University of Giessen.
    Groeger, Sabine
    Department of Periodontology, Justus-Liebig University of Giessen.
    Johansson, Anders
    Umeå University, Faculty of Medicine, Department of Odontology.
    Meyle, Jörg
    Department of Periodontology, Justus-Liebig University of Giessen.
    T helper cells from aggressive periodontitis patients produce higher levels of interleukin-1 beta and interleukin-6 in interaction with Porphyromonas gingivalis2014In: Clinical Oral Investigations, ISSN 1432-6981, E-ISSN 1436-3771, Vol. 18, no 7, p. 1835-1843Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: In this study, we analyzed the production of Interleukin-1 beta (IL-1β) and IL-6 by activated CD4+ cells obtained from aggressive periodontitis (AgP) patients in comparison with healthy subjects (HC).

    MATERIALS AND METHODS: CD4+ cells were automatically separated from lymphocytes obtained from peripheral blood of patients with AgP and healthy controls. Cells were activated for 4, 8, and 24 h with three different stimuli: anti-CD3/anti-CD28, phytohemagglutinin (PHA), and Porphyromonas gingivalis (P. gingivalis) outer membrane protein (OMP). Protein levels were measured in supernatants of activated CD4+ cells by a bead-based immunoassay (CBA). In addition, serum antibodies against P. gingivalis were determined. Data were analyzed using U test (p < 0.05).

    RESULTS: T helper cells of AgP patients activated with P. gingivalis OMP produced higher levels of IL-1β and IL-6 in comparison with healthy controls (p < 0.05). Neither the activation with anti-CD3/anti-CD28 nor the activation with PHA showed significantly different production of IL-1β and IL-6 by the cells 25 % of patients and 17 % of controls presented with high serum reactivity to P. gingivalis.

    CONCLUSION: In view of these results, it is possible to conclude that P. gingivalis contributes to the pathogenesis of AgP by inducing high levels of pro-inflammatory cytokines such as IL-1β and IL-6 by peripheral CD4+ T helper cells.

    CLINICAL RELEVANCE: In accordance with the clinical parameters and the immunological data, we suggest that full-mouth disinfection with adjunctive systemic antibiotics might be the anti-infectious non-surgical periodontal treatment of choice in this type of patients. Microbiological analyses at the beginning and at the end of the periodontal treatment are recommended. However, it is necessary to verify these data in longitudinal clinical studies.

  • 156. Gori, Francesca
    et al.
    Lerner, Ulf
    Umeå University, Faculty of Medicine, Department of Odontology. Centre for Bone and Arthritis Research at Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
    Ohlsson, Claes
    Baron, Roland
    A new WNT on the bone: WNT16, cortical bone thickness, porosity and fractures2015In: BoneKEy Reports, ISSN 2047-6396, Vol. 4, article id 669Article, review/survey (Refereed)
    Abstract [en]

    The last decade has provided abundant data implicating the WNT pathway in bone development and in the regulation of skeletal homeostasis. Rare human mutations together with gain-and loss-of-function approaches in mice have clearly demonstrated that disrupted regulation of this pathway leads to altered bone mass. In addition to these rare human and mice mutations, large population-based genome-wide association studies (GWASs) have identified single-nucleotide polymorphisms in similar to 60 loci strongly associated with variations in bone mineral density (BMD) at different skeletal sites. Among the loci/genes identified by BMD GWAS, components of the WNT signaling pathway are numerous and have been shown to contribute to skeletal development and homeostasis. Within the components of WNT signaling, the gene coding for WNT16, one of the 19 WNT ligands of the human genome, has been found strongly associated with specific bone traits such as cortical bone thickness, cortical porosity and fracture risk. Recently, the first functional characterization of Wnt16 has confirmed the critical role of Wnt16 in the regulation of cortical bone mass and bone strength in mice. These reports have extended our understanding of Wnt16 function in bone homeostasis and have not only confirmed the unique association of Wnt16 with cortical bone and fracture susceptibility, as suggested by GWAS in human populations, but have also provided novel insights into the biology of this WNT ligand and the mechanism(s) by which it regulates cortical but not trabecular bone homeostasis. Most interestingly, Wnt16 appears to be a strong anti-resorptive soluble factor acting on both osteoblasts and osteoclast precursors.

  • 157.
    Grahn, K
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Wikström, S
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Nyman, Linda
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Stecksén-Blicks, Christina
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Attitudes about dental care among parents whose children suffer from severe congenital heart disease: a case-control study2006In: International Journal of Paediatric Dentistry, ISSN 0960-7439, E-ISSN 1365-263X, Vol. 16, no 4, p. 231-238Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: To examine attitudes and experiences of parents whose children have complex congenital heart disease (CHD) with respect to dental health information and advice, dental care, and service and to compare the results with data from an age- and gender-matched control group without any medical problems.

    SETTING: Faculty of Medicine (Paediatric Cardiology and Paediatric Dentistry), Umea University, Umea, Sweden.

    SAMPLE AND METHOD: Each group comprised parents of 33 children; the children's mean age was 9.4 years. All the cases and the controls resided in the county of Vasterbotten, northern Sweden. Data were collected with a questionnaire with 20 joint questions to both groups and four additional questions to the CHD group.

    RESULTS: Of the 20 joint questions, significant differences were displayed in the following areas: the professional group that provided the parents with dental health information and advice (P < 0.01), attitudes to reception at the dental clinic, and experience of sedation before operative dental treatment (P < 0.05). Parents to 11 children with CHD who were patients at a specialist clinic for paediatric dentistry scored the reception at the dental clinic as excellent in nine cases and satisfactory in two, compared to excellent (3), satisfactory (11), decent (4), and poor (4) among those who were patients in general dental practice (P < 0.01). No statistically significant differences in educational level or in parental experience of dental health were noted between the two groups (P > 0.05).

    CONCLUSION: Children with CHD in northern Sweden mainly receive their dental health information from a physician or a dentist, and healthy children mainly receive information from a dental hygienist indicating that children with CHD are given priority in the dental care system. Parental attitudes to reception in the dental service differed, and parents of healthy children scored the reception at the dental clinic better than parents of children with CHD. It is suggested that children with severe CHD should receive dental care in clinics for paediatric dentistry, particularly at early ages.

  • 158. Grigoriadis, A
    et al.
    Johansson, Roland S
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB).
    Trulsson, M
    Temporal profile and amplitude of human masseter muscle activity is adapted to food properties during individual chewing cycles2014In: Journal of Oral Rehabilitation, ISSN 0305-182X, E-ISSN 1365-2842, Vol. 41, no 5, p. 367-373Article in journal (Refereed)
    Abstract [en]

    Jaw actions adapt to the changing properties of food that occur during a masticatory sequence. In the present study, we investigated how the time-varying activation profile of the masseter muscle changes during natural chewing in humans and how food hardness affects the profile. We recorded surface electromyography (EMG) of the masseter muscle together with the movement of the lower jaw in 14 healthy young adults (mean age 22) when chewing gelatin-based model food of two different hardness. The muscle activity and the jaw kinematics were analysed for different phases of the chewing cycles. The increase in the excitatory drive of the masseter muscle was biphasic during the jaw-closing phase showing early and late components. The transition between these components occurred approximately at the time of tooth-food contact. During the masticatory sequence, when the food was particularised, the size of the early component as well as the peak amplitude of the EMG significantly decreased along with a reduction in the duration of the jaw-closing phase. Except for amplitude scaling, food hardness did not appreciably affect the muscle's activation profile. In conclusion, when chewing food during natural conditions, masseter muscle activation adapted throughout the masticatory sequence, principally during the jaw-closing phase and influenced both early and late muscle activation components. Furthermore, the adaptation of jaw actions to food hardness was affected by amplitude scaling of the magnitude of the muscle activity throughout the masticatory sequence.

  • 159.
    Gunne, Johan
    et al.
    Umeå University, Faculty of Medicine, Odontology, Prosthetic Dentistry.
    Nyström, Elisabeth
    Umeå University, Faculty of Medicine, Odontology, Oral and Maxillofacial Surgery.
    Kahnberg, Karl-Erik
    Bone grafts and implants in the treatment of the severely resorbed maxillae: a 3-year follow-up of the prosthetic restoration.1995In: International Journal of Prosthodontics, ISSN 0893-2174, E-ISSN 1139-9791, Vol. 8, no 1, p. 38-45Article in journal (Refereed)
    Abstract [en]

    Thirty patients with severely resorbed maxillae were treated in a one-stage procedure using bone graft and implant placement. A horseshoe-shaped bone graft was taken from the iliac wing and fixed to the residual maxillary ridge using titanium implants, which supported the prostheses placed after a 6-month healing period. The material constituted two groups: a development group, the first 10 patients; and a routine group, the following 20 patients. At the 3-year follow-up, the implant survival was 87.5% and the prosthesis stability was 100% in the routine group. The probing depth did not change during the follow-up period, while the grafted region decreased in volume during the first postoperative year. The patients reported improved chewing ability and improved life quality. Very few technical and prosthodontic complications occurred.

  • 160. Gustafsson, I
    et al.
    Nyström, Elisabeth
    Umeå University, Faculty of Medicine, Odontology, Oral and Maxillofacial Surgery.
    Quiding, H
    Effect of preoperative paracetamol on pain after oral surgery.1983In: European Journal of Clinical Pharmacology, ISSN 0031-6970, E-ISSN 1432-1041, Vol. 24, no 1, p. 63-65Article in journal (Refereed)
    Abstract [en]

    A double-blind, randomized cross-over trial was carried out in 50 patients undergoing surgical removal of bilaterally impacted lower wisdom teeth. Surgery in each patient was performed twice and paracetamol 1000 mg was administered once preoperatively and once postoperatively. The time interval to additional analgesic intake and the pain intensity up to and at that time were assessed. There was no difference between the 2 treatments. It was concluded that preoperative paracetamol does not offer any clinical advantage in patients who undergo surgical removal of impacted lower wisdom teeth.

  • 161.
    Gustafsson, Nils
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Ahlqvist, Jan B.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Wester, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Medicine. Department of Clinical Sciences, Karolinska Institutet Danderyds Hospital, Stockholm, Sweden..
    Buhlin, Kare
    Gustafsson, Anders
    Levring Jäghagen, Eva
    Umeå University, Faculty of Medicine, Department of Odontology.
    Calcified carotid artery atheromas in panoramic radiographs are associated with a first myocardial infarction: a case-control study2018In: Oral surgery, oral medicine, oral pathology and oral radiology, ISSN 2212-4403, E-ISSN 2212-4411, Vol. 125, no 2, p. 199-205Article in journal (Refereed)
    Abstract [en]

    Objective. The aim of this case-control study was to investigate whether patients with a first myocardial infarction (MI) had a higher prevalence of calcified carotid artery atheromas (CCAAs) on panoramic radiographs (PRs) than age-, gender-, and residential area-matched controls without MI. Study Design. Six hundred ninety-six cases with a first MI and 696 controls were included in this substudy of the Swedish multicentre PAROKRANK study. All participants underwent panoramic radiography, and the PRs were evaluated for CCAAs. Results. The prevalence of CCAAs detected by PR was 33.8% (235 of 696) in cases and 27.6% (192 of 696) in controls (odds ratio [OR] 1.24; 95% confidence interval [CI] 1.04-1.44; P = .012). Among males, 32.7% of cases (184 of 562) and 26.5% of controls (149 of 562) displayed CCAAs on PRs (OR 1.24; 95% CI 1.03-1.48; P = .022). Among both genders, bilateral CCAAs were significantly more common among cases than among controls (P = .002). Conclusions. Cases with recent MIs had a significantly higher prevalence of CCAAs on PRs compared with controls without MIs. This difference between groups was more pronounced for bilateral CCAAs. These findings supported the hypothesis that CCAA detection could serve as a risk indicator for future MIs.

  • 162.
    Gustafsson, Nils
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Ahlqvist, Jan
    Umeå University, Faculty of Medicine, Department of Odontology.
    Levring Jäghagen, Eva
    Umeå University, Faculty of Medicine, Department of Odontology.
    Long-term skill improvement among general dental practitioners after a short training programme in diagnosing calcified carotid artery atheromas on panoramic radiographs2019In: European journal of dental education, ISSN 1396-5883, E-ISSN 1600-0579, Vol. 23, p. 54-61Article in journal (Refereed)
    Abstract [en]

    PURPOSE: To study general dental practitioners (GDPs) ability to detect calcified carotid artery atheromas (CCAAs) in panoramic radiographs (PRs) and if their diagnostic accuracy in long term is improved after a short training programme.

    METHODS: Fourteen GDPs had their diagnostic accuracy regarding CCAA in PR assessed at baseline, 2 weeks and 1 year after training. Comparison was made with a reference standard based on consensus results from two experienced oral and maxillofacial radiologists. At each session, 100 radiographs were assessed individually by the GDPs. After the baseline assessment, the GDPs participated in a 2-hour training programme comprising a lecture and diagnostic training by calibration. The GDPs results before and after training were compared, as well as between follow-up sessions.

    RESULTS: A significant improvement in diagnostic accuracy was observed with increased sensitivity (from 41.8% to 55.7%, P = 0.02) without a significant decrease in specificity (from 87.2% to 86.7%, P = 0.87). The Kappa values also increased (from 0.66 to 0.71, P = 0.04). At 1-year follow-up, the improvement compared to baseline remained significant. There were no significant changes between the 2-week and 1-year follow-up assessment.

    CONCLUSION: A short training programme can significantly and sustainable improve GDPs diagnostic accuracy regarding CCAA.

  • 163.
    Gyll, Johanna
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Ridell, Karin
    Öhlund, Inger
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Akeson, Pia Karlsland
    Johansson, Ingegerd
    Umeå University, Faculty of Medicine, Department of Odontology.
    Lif Holgerson, Pernilla
    Umeå University, Faculty of Medicine, Department of Odontology.
    Vitamin D status and dental caries in healthy Swedish children2018In: Nutrition Journal, ISSN 1475-2891, E-ISSN 1475-2891, Vol. 17, article id 11Article in journal (Refereed)
    Abstract [en]

    Background: Vitamin D is crucial for mineralized tissue formation and immunological functions. The purpose of this study was to evaluate the association between vitamin D status and dental status in healthy children with vitamin D supplementation in infancy and at 6 years of age.

    Method: Eight-year-old children who had participated, in a vitamin D intervention project when they were 6 years old were invited to participate in a dental follow-up study. They had fair or darker skin complexion and represented two geographically distant parts of Sweden. 25-hydroxy vitamin D in serum had been measured at 6 years of age and after a 3-month intervention with 25, 10 or 2 (placebo) mu g of vitamin D-3 per day. Two years later, caries and enamel defects were scored, self-reported information on e.g., oral behavior, dietary habits and intake of vitamin D supplements was collected, and innate immunity peptide LL37 levels in saliva and cariogenic mutant streptococci in tooth biofilm were analyzed. The outcome variables were caries and tooth enamel defects.

    Results: Dental status was evaluated in 85 of the 206 children in the basic intervention study. Low vitamin D levels were found in 28% at baseline compared to 11% after the intervention, and 34% reported continued intake of vitamin D supplements. Logistic regression supported a weak inverse association between vitamin D status at 6 years of age and caries 2 years later (odds ratio 0.96; p = 0.024) with minor attenuation after an adjustment for potential confounders. Multivariate projection regression confirmed that insufficient vitamin D levels correlated with caries and higher vitamin D levels correlated with being caries-free. Vitamin D status at 6 years of age was unrelated to enamel defects but was positively associated with saliva LL37 levels.

    Conclusion: An association between vitamin D status and caries was supported, but it was not completely consistent. Vitamin D status at 6 years of age was unrelated to enamel defects but was positively associated with LL37 expression.

  • 164.
    Habib, Aboud
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Shamoel, Sargon
    Umeå University, Faculty of Medicine, Department of Odontology.
    Difference in marginal and internal fit between Luxatemp crowns and Empress crowns2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose with this in-vitro study is to examine the difference in marginal and internal gap width between bis-acryl composite resins (Luxatemp Fluorescence) and IPS Empress crowns.

    A maxillary left first phantom Frasaco molar tooth placed in a maxillary Frasaco model was prepared for an all-ceramic crown. 15 provisional Luxatemp crowns were made and silicon replicas of the intermediate space between the prepared tooth and the inside of the Luxatemp crowns were made to measure the internal and marginal gap width. The silicon replicas were divided into four pieces and the gap width was measured at 240 points under microscope. The results were compared to data on internal and marginal gap width for an IPS Empress crown from a published study.

    The results of this present study showed a slight difference in marginal and internal gap width between the Luxatemp crowns and the IPS Empress crowns (control). The Luxatemp crowns have a slightly minor overall gap width than the IPS Empress crowns. The marginal and occlusal gap width was slightly wider for the Luxatemp crowns (205µm) than for the IPS Empress crowns (170µm).

    The conclusion of this study is that provisional materials made of bis-acryl composite resins give a marginal and internal fit that can be compared to the marginal and internal fit of an IPS Empress crown.

  • 165. Hallman, M
    et al.
    Lundgren, Stefan
    Umeå University, Faculty of Medicine, Odontology, Oral and Maxillofacial Surgery.
    Sennerby, L
    Histologic analysis of clinical biopsies taken 6 months and 3 years after maxillary sinus floor augmentation with 80% bovine hydroxyapatite and 20% autogenous bone mixed with fibrin glue.2001In: Clinical Implant Dentistry and Related Research, ISSN 1523-0899, E-ISSN 1708-8208, Vol. 3, no 2, p. 87-96Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Bovine hydroxyapatite (Bio-Oss, Geistlich Pharmaceutical, Wollhausen, Switzerland) has been suggested to be used in maxillary sinus floor augmentation procedures prior to or in conjunction with implant placement. However, the long-term histologic fate of this material is not well understood. PURPOSE: The aim with this study was to histologically evaluate the tissue response in patients to a mixture of bovine hydroxyapatite (BH), autogenous bone, and fibrin glue 6 months and 3 years after a maxillary sinus floor augmentation procedure. MATERIALS AND METHOD: Biopsies were taken from a group of 20 consecutive patients 6 months (n = 16) and 3 years (n = 12) after maxillary sinus floor augmentation with a mixture of BH (80%), autogenous bone (20%), and fibrin glue and prepared for histologic analysis. RESULTS: Light microscopy and morphometry from biopsies taken after 6 months showed various amounts of mineralized bone tissue. The specimen area was occupied by 54.1 +/- 12.6% nonmineralized tissue, followed by 21.2 +/- 24.5% lamellar bone, 14.5 +/- 10.3% BH particles, and 10.2 +/- 13.4% woven bone. The nonmineralized tissue seen in bone-forming areas consisted of a loose connective tissue, rich with vessels and cells. There were no signs of resorption of the BH particles. The lamellar bone appeared to have originated from the recipient site and was seldom in contact with the BH particles. After 3 years, the nonmineralized tissue area had decreased to 36.0 +/- 19.0% (p < .05) and consisted mainly of bone marrow tissue. The surface area of lamellar bone had increased to 50.7 +/- 22.8% (p < .05), and there was almost no immature bone. The mean specimen area occupied by BH particles, was 12.4 +/- 8.7% and had not changed from 6 months (not significant). Moreover, the sizes of the particles were similar after 6 months and 3 years. The degree of BH particle-bone contact had increased from 28.8% +/- 19.9% after 6 months to 54.5 +/- 28.8% after 3 years (p < .05). CONCLUSION: Histology of specimens from maxillary sinuses augmented with 80% BH particles, 20% autogenous bone, and fibrin glue showed a positive bone tissue response after 6 months and 3 years after augmentation of the maxillary sinus floor prior to implant placement in a group fo 20 patients. The bone surrounding and in contact with the BH particles after 6 months was mainly immature woven bone, which with time was replaced by mature lamellar bone filling the interparticle space as observed in the 3-year specimens. Moreover, bone-integrated BH particles seem to be resistant to resorption. The results indicate that the procedure may be considered when only small amounts of intraoral autogenous bone graft are available.

  • 166.
    Hallman, Mats
    et al.
    Umeå University, Faculty of Medicine, Odontology, Oral and Maxillofacial Surgery.
    Cederlund, Andreas
    Lindskog, Sven
    Lundgren, Stefan
    Umeå University, Faculty of Medicine, Odontology. Umeå University, Faculty of Medicine, Odontology, Oral and Maxillofacial Surgery.
    Sennerby, Lars
    A clinical histologic study of bovine hydroxyapatite in combination with autogenous bone and fibrin glue for maxillary sinus floor augmentation. Results after 6 to 8 months of healing.2001In: Clinical Oral Implants Research, ISSN 0905-7161, E-ISSN 1600-0501, Vol. 12, no 2, p. 135-143Article in journal (Refereed)
    Abstract [en]

    Biopsies were taken from 16 out of 20 consecutive referral patients 6 to 8 months after maxillary sinus floor augmentation with a mixture of bovine hydroxyapatite (BH), autogenous bone particles and fibrin glue. Four days prior to biopsy retrieval the patients were given a single dose of tetracycline to label bone forming sites. Fluorescence microscopy of 100 microm thick sections revealed active bone formation in conjunction with the BH particles in 14 of 15 specimens analysed. Light microscopy and morphometry of ground sections from 16 patients showed various amounts of mineralised bone tissue in all except one specimen. In the latter case, the BH particles were encapsulated by a dense fibrous connective tissue. Sections from the augmented areas were occupied by non-mineralized tissue (54.1+12.6%), lamellar bone (21.2+24.5%), BH particles (14.5+10.3%) and woven bone (10.2+13.4%). The non-mineralized tissue seen in bone forming areas consisted of a loose connective tissue, rich of vessels and cells, and in the periphery of a more dense fibrous connective tissue. Woven bone with large and scattered osteocyte lacunae was bridging between the BH particles and the lamellar trabecular bone. There were no signs of resorption of the BH particles. The lamellar bone appeared to have originated from the recipient site and was seldom in contact with the BH particles. It is concluded that the tested implant material has bone conducting properties. The bone associated with the BH particles after 6 to 8 months of healing was mainly woven.

  • 167.
    Hallman, Mats
    et al.
    Umeå University, Faculty of Medicine, Odontology, Oral and Maxillofacial Surgery.
    Hedin, Måns
    Sennerby, Lars
    Lundgren, Stefan
    Umeå University, Faculty of Medicine, Odontology. Umeå University, Faculty of Medicine, Odontology, Oral and Maxillofacial Surgery.
    A prospective 1-year clinical and radiographic study of implants placed after maxillary sinus floor augmentation with bovine hydroxyapatite and autogenous bone.2002In: Journal of oral and maxillofacial surgery (Print), ISSN 0278-2391, E-ISSN 1531-5053, Vol. 60, no 3, p. 277-284; discussion 285Article in journal (Refereed)
    Abstract [en]

    PURPOSE: The purposes of this study were 1) to evaluate the survival rate of implants placed in maxillary sinuses augmented with bovine hydroxyapatite and autogenous bone 6 months before implant surgery and 2) to estimate dimensional changes of the bone graft with time using a new radiographic method. PATIENTS AND METHODS: Thirty maxillary sinuses in 20 consecutive patients with severe resorption (mean, 3.8 mm of remaining alveolar bone) were augmented with a mixture of 80% bovine hydroxyapatite and 20% autogenous bone mixed with fibrin glue to enable the placement of screw-shaped dental implants. After 6 months of primary healing, 108 implants were placed and followed with clinical and radiographic examinations during the first year of loading. Measurements of changes in height, width, and length of the grafted material were made on tomographic Scanora (Soredex Orion Corporation Ltd, Helsinki, Finland) and panoramic radiographs taken 3 and 12 months after grafting and after 1 year of bridge loading. RESULTS: Ten implants in 6 patients were lost during the study (9 before loading and 1 after 1 year of functional loading), for a survival rate of 90.7%. All patients received fixed restorations, and the bridge survival rate was 100% after 1 year of loading. Small (<10%) but statistically significant dimensional changes in the grafted material were seen during the study period. CONCLUSIONS: Acceptable short-term results can be obtained with implants placed after the use of bovine hydroxyapatite and autogenous bone for maxillary sinus floor augmentation. These grafts show good resistance to resorption.

  • 168.
    Hallman, Mats
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology, Oral and Maxillofacial Surgery. Department of Oral and Maxillofacial Surgery, Public Health Service, Gävle, Sweden; Center for Research and Development, Uppsala University/Gävleborg County Council, Gävleborg, Sweden.
    Mordenfeld, Arne
    Strandkvist, Tomas
    Bone replacement following dental trauma prior to implant surgery: present status2009In: Dental Traumatology, ISSN 1600-4469, E-ISSN 1600-9657, Vol. 25, no 1, p. 2-11Article, review/survey (Refereed)
    Abstract [en]

    Dento-alveolar trauma often leads to a need for reconstruction of the alveolar crest before an implant can be placed. Although autogenous bone grafts is considered the 'gold standard', this may be associated with patient morbidity and graft resorption. Consequently, the use of bone substitutes has increased. Today, a substantial number of biomaterials are available on the market, but only a few are well documented. The user should be aware that these biomaterials have different properties: resorbable or non-resorbable, time of resorption and resorption mechanism. The purpose of this review is to describe the function of various bone substitutes and indications for their use in reconstructive implant surgery and to give an overview of the current situation.

  • 169.
    Hallman, Mats
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology, Oral and Maxillofacial Surgery.
    Sennerby, Lars
    Lundgren, Stefan
    Umeå University, Faculty of Medicine, Department of Odontology. Umeå University, Faculty of Medicine, Department of Odontology, Oral and Maxillofacial Surgery.
    A clinical and histologic evaluation of implant integration in the posterior maxilla after sinus floor augmentation with autogenous bone, bovine hydroxyapatite, or a 20:80 mixture.2002In: International Journal of Oral & Maxillofacial Implants, ISSN 0882-2786, E-ISSN 1942-4434, Vol. 17, no 5, p. 635-643Article in journal (Refereed)
    Abstract [en]

    PURPOSE: This study was designed to clinically and histologically evaluate the integration of titanium implants in different grafting materials used for maxillary sinus augmentation procedures. MATERIALS AND METHODS: A total of 21 patients and 36 maxillary sinuses were augmented with (1) autogenous particulated bone from the mandibular ramus, (2) bovine hydroxyapatite (BH) with membrane coverage, or (3) an 80/20 mixture of BH and autogenous bone. The grafts were allowed to heal for 6 to 9 months prior to placement of microimplants for histology and standard implants for prosthetic rehabilitation. After another 6 months of healing, when abutments were connected, the microimplants were retrieved for histologic and morphometric analyses. The outcome of the standard implants was clinically evaluated after 1 year of loading. RESULTS: The mean bone-implant contact was 34.6 +/- 9.5%, 54.3 +/- 33.1%, and 31.6 +/- 19.1% for autogenous bone, mixture of 20% autogenous bone/80% BH, and 100% BH, respectively. The corresponding values for the bone area parameter were 37.7 +/- 31.3%, 39.9 +/- 8%, and 41.7 +/- 26.6%. The BH area was found to be 12.3 +/- 8.5% and 11.8 +/- 3.6% for 20% autogenous bone/80% BH and 100% BH, respectively. There were no statistically significant differences for any parameter between any of the groups. After 1 year of loading, 6 of the 33 implants placed in autogenous bone grafts, 2 of the 35 implants placed in the BH/autogenous bone mixture, and 2 of 43 implants placed in BH were lost. There were no statistically significant differences between any of the groups. DISCUSSION: The histomorphometric analysis showed no differences between the 3 groups, indicating that autogenous bone graft can be substituted with bovine hydroxyapatite to 80% or 100% when used for maxillary sinus floor augmentation. The effect of adding autogenous bone remains unclear but may allow for a reduction of the healing time. CONCLUSION: The results from this clinical and histologic study indicate that similar short-term results can be expected when using autogenous bone, BH, or a mixture of them for maxillary sinus floor augmentation and delayed placement of dental implants.

  • 170.
    Hanna, Carola
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology, School of Dentistry.
    Sabet Motlagh, Tina
    Umeå University, Faculty of Medicine, Department of Odontology, School of Dentistry.
    Inflammatory markers in sera in patients diagnosed with mucosal lichen planus2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    OBJECTIVE: Lichen planus is a disease that can affect both skin and mucosa, in some cases both at the same time. Among patients with lichen planus, the oral version of lichen planus (OLP) can be observed in 50 – 70 %. OLP is the most common chronic inflammatory disease of oral mucosa. Today it is known that OLP is an inflammatory condition but it is not known exactly what substances are prominent and active during this specific inflammatory process. The aim of this study was to examine inflammatory factors involved in OLP. METHODS: A total of 24 individuals were included in this prospective study. 15 of these were patients diagnosed with mucosal LP, whereas the other nine were healthy controls. Blood samples were taken from all participants and sent to Life Science Lab in Uppsala where they used Olinks inflammation panel to analyse inflammatory markers in the blood samples. RESULTS: There were differences in inflammatory factors in blood between the controls and patients with mucosal lichen planus. The inflammatory factors that contributed the most to this difference were IL-5, SCF, FGF-19 and FGF-21. CONCLUSIONS: Due to the differences between LP-patients and controls we can conclude that there are tendencies to an inflammatory process going on systemically involving different levels of mainly IL-5, SCF, FGF-19 and FGF-21. The inflammatory factors that contributed the most to the differences between the two groups are not the typical ones that have been the resulting elevated inflammatory factors in other previous studies.

  • 171.
    Hansson, Lena
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Stecksen-Blicks, Christina
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Oral microflora and dietary intake in infants with congenital heart disease: a case control study2012In: European Archives of Paediatric Dentistry, ISSN 1818-6300, E-ISSN 1996-9805, Vol. 13, no 5, p. 238-243Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Infants with moderate to severe congenital heart disease (CHD) are at a higher risk for growth failure and malnutrition due to increased metabolic demands and inadequate energy intake. This state requires meals that are more frequent and a special enriched diet, which may have negative implications on oral health.

    AIM: To examine the oral colonisation of some bacteria associated with caries development during infancy; mutans streptococci (MS) and lactobacilli (LCB) in infants with CHD and whether their dietary intake had an impact on the bacterial levels.

    DESIGN: This was a prospective case-control study. 11 infants with CHD and 22 healthy, age-matched infants were enrolled. Saliva samples and food diaries were collected at 6, 9, and 12 months of age. The total viable counts of MS and LCB in saliva were determined, and energy intake, meal frequency, intake of proteins, fat, carbohydrates and sucrose were calculated.

    RESULTS: At 12 months of age, the MS count was higher in the CHD group than in the controls (p<0.01), and MS constituted a higher ratio of the total viable count of oral bacteria (p<0.01). Meal frequency was higher in the CHD group at 6 and 9 months of age than in the controls (p<0.05). The intake of sucrose did not differ between the groups, while the total carbohydrate intake was higher in the control group at 6 and 12 months of age (p<0.05). Compared with the control group, which had six courses of antibiotic administration, the CHD infants had 21 courses (p<0.05).

    CONCLUSIONS: Infants with severe CHD have higher levels of MS at 12 months of age than the healthy controls. A higher meal frequency and use of diuretic medication and antibiotics may have influenced MS colonisation.

  • 172.
    Hansson, Patrik
    et al.
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Sunnegårdh-Grönberg, Karin
    Umeå University, Faculty of Medicine, Department of Odontology, Dental Hygiene.
    Bergdahl, Jan
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Bergdahl, Maud
    Nyberg, Lars
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Physiology. Umeå University, Faculty of Medicine, Umeå Centre for Functional Brain Imaging (UFBI). Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Nilsson, Lars-Göran
    Relationship between natural teeth and memory in a healthy elderly population2013In: European Journal of Oral Sciences, ISSN 0909-8836, E-ISSN 1600-0722, Vol. 121, no 4, p. 333-340Article in journal (Refereed)
    Abstract [en]

    The relationship between mastication and cognitive function remains unclear, but both animal and experimental human studies suggest a possible causal relationship. In the present study it was hypothesized that natural teeth are of importance for hippocampus-based cognitive processes, such as episodic long-term memory. A population-based sample of 273 participants (55-80yr of age; 145 women) was investigated in a cross-sectional study. The participants underwent health assessment, completed a battery of cognitive tests, and took part in an extensive clinical oral examination. The number of natural teeth contributed uniquely and significantly to explaining variance (3-4%) in performance on measures of episodic memory and semantic memory over and above individual differences in age, years of education, gender, occupation, living conditions, and medical history. The number of natural teeth did not have an influence on the performance of measures of working memory, visuospatial ability, or processing speed. Within the limitations of the current study, a small, but significant, relationship between episodic memory and number of natural teeth is evident.

  • 173. Harnesk Nygren, Helen
    et al.
    Blomstrand, Lena
    Graming Legert, Karin
    Magnusson, Mikael
    Sjöström, Mats
    Svensk Käkkirurgisk förening.
    Lund, Bodil
    Rekommendation för antibiotika till patienter som strålbehandlats mot munhålan2016In: Tandläkartidningen, ISSN 0039-6982, no 5, p. 58-59Article in journal (Other academic)
  • 174.
    Hasslöf, Pamela
    Umeå University, Faculty of Medicine, Department of Odontology.
    Probiotic Lactobacilli in the context of dental caries as a biofilm-mediated disease2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background: The World Health Organization defines probiotics as ‘live microorganisms which, when administered in adequate amounts, confer a health benefit to the host’. Traditionally, probiotic microorganisms have been used to prevent or treat gastrointestinal tract diseases. In the last 15 years, there has been increasing interest of a possible probiotic impact on the oral microbiota and dental caries. Dental caries is a multifactorial disease, and the causative factor in the oral microbiota includes a shift from a balanced microflora to a microflora that includes more aciduric species such as mutans streptococci (MS), non-mutans streptococci, and Actinomyces. MS is considered an opportunistic pathogen although several other bacteria also contribute to the disease. Early acquisition of MS is associated with early development of caries; therefore a desirable complement to other prophylactic measures would be a MS colonization inhibitor.

    Objective: To better understand how selected strains of probiotic lactobacilli interact with MS in vitro and in vivo and to study the impact of probiotic lactobacilli on caries development during childhood.

    Material and methods: The in vitro properties of probiotic lactobacilli were studied with regard to (i) acid production from sugars and sugar alcohols, (ii) growth inhibition capacity on clinical isolates and reference strains of MS as well as Candida albicans and (iii) the capacity to co-aggregate with MS. A randomized controlled trial (RCT) tested the short-term effect of intervention with two Lactobacillus reuteri strains on MS, which was evaluated after treatment with chlorhexidine. The re-growth patterns of MS and 19 other selected strains were also evaluated. In the second clinical study  we investigated the long-term effect on MS prevalence and dental caries after an intervention with Lactobacillus paracasei ssp. paracasei F19 (LF19) between 4 and 13 months of age.

    Results: The results from the in vitro testing showed that strains of probiotic lactobacilli differed in their fermentation patterns, inhibition capacity and their capacity to co-aggregate, which should be kept in mind in the translation to clinical research. The clinical study on short-term effects of two L. reuteri strains on MS and other oral strains showed no effect on re-growth patterns after intervention. The clinical study on long-term effects of LF19 showed no effect on the prevalence of MS. Furthermore, the clinical follow-up at 9 years of age showed no differences in either decayed, missing, and filled surface (dmfs) or DMFS between the probiotic and placebo groups. Evaluation of saliva samples showed no signs of oral colonization with LF19 in the study group.

    Conclusion: The in vitro testing showed potentials of the selected probiotic Lactobacillus strains for interference with MS and C. albicans. The results from the clinical studies showed no such effect on MS or dental caries. Evidence regarding the effectiveness of specific probiotic applications in the prevention of dental caries is limited and does not allow for conclusions concerning the use of probiotic bacteria as a preventive measure.

  • 175.
    Hasslöf, Pamela
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Hedberg, Maria
    Umeå University, Faculty of Medicine, Department of Odontology, Oral Microbiology.
    Twetman, Svante
    Stecksén-Blicks, Christina
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Growth inhibition of oral mutans streptococci and candida by commercial probiotic lactobacilli: an in vitro study2010In: BMC Oral Health, ISSN 1472-6831, E-ISSN 1472-6831, Vol. 10, p. 18-Article in journal (Refereed)
    Abstract [en]

    The selected probiotic strains showed a significant but somewhat varying ability to inhibit growth of oral mutans streptococci and Candida albicans in vitro.

  • 176.
    Hasslöf, Pamela
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Twetman, Svante
    Caries prevalence in children with cleft lip and palate: a systematic review of case-control studies2007In: International Journal of Paediatric Dentistry, ISSN 0960-7439, E-ISSN 1365-263X, Vol. 17, no 5, p. 313-319Article in journal (Refereed)
    Abstract [en]

    AIM: To conduct a systematic review of literature in order to examine the evidence of an increased prevalence of dental caries in children with cleft lip and palate (CLP).

    METHODS: A search of the PubMed database was conducted through May 2006. Sex- and age-matched case-control studies with noncavitated and manifest caries lesions as endpoint were targeted (n = 6). The studies were assessed independently by two reviewers and scored A-C according to predetermined criteria for methodology and performance.

    RESULTS: Significantly more caries in CLP children were reported in two of the four studies in the permanent dentition and in three out of four publications dealing with primary teeth. None of the articles were, however, assessed with the highest grade 'A' and the level of evidence was therefore based on three papers graded 'B'. There was a tendency towards higher caries scores in preschool children, but as conflicting results were revealed, the evidence that children with CLP exhibit more caries than noncleft controls was inconclusive.

    CONCLUSION: This systematic review of literature was unable to find firm evidence for the assumption that CLP children have an increased prevalence of dental caries.

  • 177.
    Hasslöf, Pamela
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    West, Christina
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Karlsson Videhult, Frida
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Brandelius, Charlotte
    Umeå University, Faculty of Medicine, Department of Odontology.
    Stecksén-Blicks, Christina
    Umeå University, Faculty of Medicine, Department of Odontology.
    Early intervention with probiotic Lactobacillus paracasei F19 has no long-term effect on caries experience2013In: Caries Research, ISSN 0008-6568, E-ISSN 1421-976X, Vol. 47, no 6, p. 559-565Article in journal (Refereed)
    Abstract [en]

    The aim of the study was to evaluate possible long-term effects of a cereal diet supplemented with Lactobacillus paracasei F19 (LF19) during weaning on caries experience, mutans streptococci (MS) and lactobacilli (LBC) in a group of 9-year-old children. A secondary aim was to evaluate if the intervention resulted in the permanent integration of LF19 as part of the oral microbiota. The study followed up on a double-blind placebo-controlled randomised trial. Among 179 infants that were randomised to a daily diet that included cereals with or without LF19 from 4 to 13 months of age, 56 from the probiotic group and 62 from the placebo group participated in the follow-up at 9 years. Data were collected by oral clinical examination and questionnaires. MS and LBC levels were assessed with conventional cultivation; LF19 was detected by using randomly amplified polymerase chain reactions (RAPD-PCR). At the follow-up, neither decayed, missing and filled surfaces for primary teeth (dmfs) nor decayed, missing and filled surfaces for permanent teeth (DMFS) differed significantly between the probiotic and placebo groups (p > 0.05). MS and LBC levels were similar in both groups (p > 0.05). RAPD-PCR showed no evidence of oral colonisation with LF19 in the study group. It is concluded that an early intervention with LF19 did not affect the frequency of dental caries, MS or LBC. LF19 did not establish itself as a permanent facet of the oral microbiota in any of the subjects included in this study.

  • 178.
    Haubek, Dorte
    et al.
    Århus universitet.
    Johansson, Anders
    Umeå University, Faculty of Medicine, Department of Odontology.
    Pathogenicity of the highly leukotoxic JP2 clone of Aggregatibacter actinomycetemcomitans and its geographic dissemination and role in aggressive periodontitis2014In: Journal of Oral Microbiology, ISSN 2000-2297, E-ISSN 2000-2297, Vol. 6, article id 23980Article in journal (Refereed)
    Abstract [en]

    For decades, Aggregatibacter actinomycetemcomitans has been associated with aggressive forms of periodontitis in adolescents. In the middle of the 1990s, a specific JP2 clone of A. actinomycetemcomitans, belonging to the cluster of serotype b strains of A. actinomycetemcomitans and having a number of other characteristics, was found to be strongly associated with aggressive forms of periodontitis, particularly in North Africa. Although several longitudinal studies still point to the bacterial species, A. actinomycetemcomitans as a risk factor of aggressive periodontitis, it is now also widely accepted that the highly leukotoxic JP2 clone of A. actinomycetemcomitans is implicated in rapidly progressing forms of aggressive periodontitis. The JP2 clone strains are highly prevalent in human populations living in Northern and Western parts of Africa. These strains are also prevalent in geographically widespread populations that have originated from the Northwest Africa. Only sporadic signs of a dissemination of the JP2 clone strains to non-African populations have been found despite Africans living geographically widespread for hundreds of years. It remains an unanswered question if a particular host tropism exists as a possible explanation for the frequent colonization of the Northwest African population with the JP2 clone. Two exotoxins of A. actinomycetemcomitans are known, leukotoxin (LtxA) and cytolethal distending toxin (Cdt). LtxA is able to kill human immune cells, and Cdt can block cell cycle progression in eukaryotic cells and thus induce cell cycle arrest. Whereas the leukotoxin production is enhanced in JP2 clone strains thus increasing the virulence potential of A. actinomycetemcomitans, it has not been possible so far to demonstrate such a role for Cdt. Lines of evidence have led to the understanding of the highly leukotoxic JP2 clone of A. actinomycetemcomitans as an aetiological factor of aggressive periodontitis. Patients, who are colonized with the JP2 clone, are likely to share this clone with several family members because the clone is transmitted through close contacts. This is a challenge to the clinicians. The patients need intense monitoring of their periodontal status as the risk for developing severely progressing periodontal lesions are relatively high. Furthermore, timely periodontal treatment, in some cases including periodontal surgery supplemented by the use of antibiotics, is warranted. Preferably, periodontal attachment loss should be prevented by early detection of the JP2 clone of A. actinomycetemcomitans by microbial diagnostic testing and/or by preventive means.

  • 179. Haworth, Simon
    et al.
    Shungin, Dmitry
    Umeå University, Faculty of Medicine, Department of Odontology.
    Kwak, So Young
    Kim, Hae-Young
    West, Nicola X.
    Thomas, Steven J.
    Franks, Paul W.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Department of Clinical Sciences, Genetic and Molecular Epidemiology Unit, Lund University, Skåne University Hospital Malmo, Malmö, Sweden; Department of Nutrition, Harvard T. H. Chan School of Public Health, Boston, MA, USA.
    Timpson, Nicholas J.
    Shin, Min-Jeong
    Johansson, Ingegerd
    Umeå University, Faculty of Medicine, Department of Odontology.
    Tooth loss is a complex measure of oral disease: determinants and methodological considerations2018In: Community Dentistry and Oral Epidemiology, ISSN 0301-5661, E-ISSN 1600-0528, Vol. 46, no 6, p. 555-562Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: Counts of missing teeth or measures of incident tooth loss are gaining attention as a simple way to measure dental status in large population studies. We explore the meaning of these metrics and how missing teeth might influence other measures of dental status.

    METHODS: An observational study was performed in 2 contrasting adult populations. In total, 62 522 adult participants were available with clinically assessed caries and periodontal indices from the Swedish arm of the Gene-Lifestyle Interactions and Dental Endpoints Study (GLIDE) and the Korea National Health and Nutrition Examination Survey (KNHANES) in the Republic of Korea. Longitudinal measures of tooth loss were available for 28 244 participants in GLIDE with median follow-up of 10.6 years.

    RESULTS: In longitudinal analysis, hazard for tooth loss was associated with baseline dental status (previous tooth loss, periodontal status and caries status) and socio-demographic variables (age, smoking status and highest educational level). Analysis of cross-sectional data suggested that indices of caries exposure were not independent of periodontal status. The strength and direction of association varied between groups, even for measures specifically intended to avoid measuring tooth loss. Individuals with impaired periodontal health (community periodontal index [CPI] 3 or higher in any sextant) had higher standardized decayed and filled surfaces (DFS; number of DFS divided by total number of tooth surfaces) in GLIDE (incidence risk ratio [IRR] 1.05 [95% CI: 1.04, 1.07], but lower standardized DFS in KNHANES (IRR: 0.95 [0.92, 0.98]) than individuals with better periodontal health (CPI <3 in all sextants).

    CONCLUSIONS: Incident tooth loss is a complex measure of dental disease, with multiple determinants. The relative importance of dental caries and periodontal disease as drivers of tooth loss differs between age groups. Measures of dental caries exposure are associated with periodontal status in the studied populations, and these associations can be population-specific. Consideration of the study-specific properties of these metrics may be required for valid inference in large population studies.

  • 180.
    Hedberg, Maria
    et al.
    Umeå University, Faculty of Medicine, Odontology, Oral Microbiology.
    Asikainen, Sirkka
    Umeå University, Faculty of Medicine, Odontology, Oral Microbiology.
    Growth inhibition of Porphyromonas gingivalis biofilm by lactobacilli2007Report (Other academic)
    Abstract [en]

    Background. Chronic periodontitis is one of the most common infectious diseases of the oral cavity. Dental plaque contains a mix of oral bacteria, and grows as biofilm on tooth surfaces. One of the bacterial species associated with periodontitis is Porphyromonas gingivalis, a Gram-negative anaerobic rod. Lactobacilli are used in probiotic products and are known to play an important role in the management of health by stimulating the immune system and contributing to the balance of the normal microflora. The knowledge of probiotic effects on oral bacteria is at present limited.

    Purpose. Lactobacillus reuteri, and Lactobacillus acidophilus are two species used in different probiotic products. In the presence of glycerol L. reuteri produces an antimicrobial product, 3-hydroxypropionaldehyd, also called reuterin. The purpose of the study was to examine the impact of L. reuteri and L. acidophilus on biofilm formed by P. gingivalis.

    Methods. To study whether L. reuteri and L. acidophilus had ability to alter the biofilm formation of P. gingivalis, 108 CFU/mL P. gingivalis and 108 CFU/mL of one of the lactobacilli were co-cultured in Brucella broth using cell-culture plates. After 48 h incubation the broth was removed and the biofilm studied by microscopy, crystal violet staining with subsequent absorbance measurements at 590 nm. Viable bacterial cells were determined in the biofilm and in the removed growth medium.

    Results. P. gingivalis and L. reuteri cultured individually formed heavy layers of biofilm (A590=2.1-3.1), whereas L. acidophilus gave a very thin layer (A590=0.21-0.35). In the biofilm competition assay, the level of viable P. gingivalis cells were reduced by at least 3 logs regardless the addition of glycerol when co-cultured with L. reuteri or L. acidophilus. In presence of glycerol, both P. gingivalis and L. reuteri were reduced below the detection level after 48 h incubation.

    Even though P. gingivalis cultured as single species formed a dense biofilm this was strongly reduced when co-cultured with L. acidophilus.

    Conclusion. In summary, the observed glycerol-dependent growth inhibition of P. gingivalis by L. reuteri seemed to be due to reuterin production. Competition in the biofilm model appeared to favor both lactobacillus species tested at the expense of P. gingivalis. The lactobacilli were able to strongly inhibit or suppress the growth of a major periodontal pathogen in the biofilm-competition assay.

  • 181.
    Hedberg, Maria
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology, Oral Microbiology.
    Hasslöf, Pamela
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Sjöström, I
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Twetman, S
    Stecksén-Blicks, Christina
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Sugar fermentation in probiotic bacteria: an in vitro study2008In: Oral Microbiology and Immunology, ISSN 0902-0055, E-ISSN 1399-302X, Vol. 23, no 6, p. 482-485Article in journal (Refereed)
    Abstract [en]

    INTRODUCTION: Food supplemented with probiotic bacteria is a rapidly growing sector of the market. The aim of the present study was to evaluate and compare the acid production of selected probiotic strains available in commercial products.

    METHODS: Six Lactobacillus strains (Lactobacillus plantarum 299v and 931; Lactobacillus rhamnosus GG and LB21; Lactobacillus paracasei subsp. paracasei F19, and Lactobacillus reuteri PTA 5289) were cultivated at 37 degrees C in an anaerobic atmosphere on Man, Rogosa, Shape (MRS) agar for 48 h or MRS broth for 16 h. After centrifugation, the cells were washed and resuspended in sterile phosphate-buffered saline and immediately subjected to a fermentation assay with 12 different carbohydrates (nine sugars and three sugar alcohols) in microtiter plates with a pH indicator. The plates were examined for color changes after 24, 48, and 72 h of incubation under aerobic and anaerobic conditions. Three scores were used: negative (pH > 6.8); weak (pH 5.2-6.8), and positive (pH < 5.2). The strains were characterized with the API 50 CH system to confirm their identity.

    RESULTS: L. plantarum fermented all the sugars except for melibiose, raffinose, and xylitol. Both L. rhamnosus strains were generally less active although L. rhamnosus GG was slightly more active than strain LB21 in the 5% CO(2) setting. The latter strain exhibited negative reactions for sucrose, maltose, arabinose, and sorbitol under anaerobic conditions. The assays with L. paracasei and L. reuteri had negative or weak reactions for all tested sugars under both aerobic and anaerobic conditions.

    CONCLUSION: The metabolic capacity to form acid from dietary sugars differed significantly between the various probiotic strains.

  • 182.
    Hedberg, Maria
    et al.
    Umeå University, Faculty of Medicine, Odontology, Oral Microbiology.
    Karched, Maribasappa
    Asikainen, Sirkka
    Umeå University, Faculty of Medicine, Odontology, Oral Microbiology.
    In-vitro growth inhibition of periodontitis-associated species by Lactobacillus reuteri2006Report (Other academic)
    Abstract [en]

    Purpose. Lactobacillus reuteri, a species used in probiotic products, produces in vitro a bacteriocin, reuterin, in the presence of glycerol. The purpose of the study was to investigate in vitro whether L. reuteri strains inhibit the growth of periodontal pathogens.

    Methods. The inhibition study was based on a disk-diffusion method. The periodontitis-associated bacteria were pre-grown for 20 h in Brucella broth or Brucella blood agar at 37oC in anaerobic atmosphere. Standardization of bacterial inocula used in the assay was made by determinations of optical density, microscopic counting of cells, and viable count. Brucella blood agar plates, without or with glycerol (100 mM), were seeded with standardized inocula of the periodontal pathogens Fusobacterium nucleatum (IDH 4186), Porphyromonas gingivalis (ATCC 33277), Prevotella intermedia (ATCC 25611), and Actinobacillus actinomycetemcomitans (SA 1398). The lactobacilli L. reuteri ATCC 55730 and L. reuteri PTA 5289 were grown for 16 h in MRS broth. A 20-L aliquot of the suspension containing 107 CFU/mL was used to soak 6-mm paper disks, which were placed on Brucella agar plates (diameter 14 cm), seeded with each periodontal pathogen separately. The plates were then incubated for 3 - 7 days in anaerobic atmosphere at 37oC before measuring the inhibition zones.

    Results. On Brucella blood agar plates seeded with periodontal pathogens, no inhibition zones were seen around the paper discs. When glycerol was added to the agar, zones of 26 to 118 mm appeared. Sizes of the zones depended on the L. reuteri strain, the periodontal pathogen, and the sizes of their inocula. L. reuteri PTA 5289 had a stronger (7-30%) inhibitory effect than L. reuteri ATCC 55730 on all periodontal species. P. gingivalis was the most susceptible species among the tested strains.

    Conclusion. Both L. reuteri strains strongly inhibited or suppressed the growth of the tested periodontitis-associated bacteria in the presence of glycerol. The inhibitory activity of L. reuteri PTA 5289 was consistently higher than that of L. reuteri ATCC 55730. The results suggest that the inhibition activity of the tested lactobacilli was related to reuterin.

  • 183.
    Hedin, Måns
    Umeå University, Faculty of Medicine, Department of Odontology.
    Röntgenbilden av tändernas rotkanaler: en experimentell undersökning1972Doctoral thesis, comprehensive summary (Other academic)
  • 184.
    Hedlund, Sven-Olof
    et al.
    Umeå University, Faculty of Medicine, Odontology, Dental Materials Science.
    Johansson, N Gunnar
    Umeå University, Faculty of Medicine, Odontology, Dental Materials Science.
    Sjögren, Göran
    Umeå University, Faculty of Medicine, Odontology, Dental Materials Science.
    A retrospective study of pre-fabricated carbon fibre root canal posts.2003In: Journal of Oral Rehabilitation, ISSN 0305-182X, E-ISSN 1365-2842, Vol. 30, no 10, p. 1036-40Article in journal (Refereed)
    Abstract [en]

    Although pre-fabricated carbon fibre posts have been used during the past decade clinical evaluations of the technique are still few. Using dental records and radiographs the clinical performance of 65 pre-fabricated carbon fibre posts (Composipost and Endopost) placed in 48 patients who regularly visited a general practice were evaluated in the present study. After an average time of 2.3 +/- 0.8 years (median 2.1 years, range 1-4.9 years) of clinical service the failure rate was 3%. Failure occurred in one tooth with a single crown restoration and in one tooth that was part of a cantilever fixed partial denture. Although the failure rate is lower than those mostly reported for metallic posts and cores more clinical studies are necessary to assess the suitability of pre-fabricated carbon fibre posts for routine use as an alternative to individually cast posts.

  • 185.
    Hedlund, Sven-Olof
    et al.
    Umeå University, Faculty of Medicine, Odontology, Dental Materials Science.
    Johansson, N Gunnar
    Umeå University, Faculty of Medicine, Odontology, Dental Materials Science.
    Sjögren, Göran
    Umeå University, Faculty of Medicine, Odontology, Dental Materials Science.
    Retention of prefabricated and individually cast root canal posts in vitro.2003In: British Dental Journal, ISSN 0007-0610, E-ISSN 1476-5373, Vol. 195, no 3, p. 155-158Article in journal (Refereed)
    Abstract [en]

    Objectives: The aim of the study was to evaluate the retention of prefabricated root canal posts made of a variety of materials that have recently been introduced into dentistry.

    Materials and methods: The posts studied were CosmoPost, Composipost carbon fibres, Composipost Æstheti-Plus, Composipost Light-Post, and Para Post Fiber White. The posts were luted in extracted human premolars and the cores were built up with the resin composites recommended by the manufactures. The retention of individually cast gold alloy posts luted with zinc-phosphate cement were used as reference. A universal testing machine was used to determine the retention of each cemented post. Data were compared using ANOVA supplemented with Fisher’s PLSD at a significance level of p < 0.05.

    Results: Only the CosmoPost system exhibited retention values that were significantly lower then for the conventionally cast gold alloy posts luted with zinc-phosphate cement. The force necessary to loosen the CosmoPost specimens was significantly less than that needed to loosen the Composipost Æstheti-Plus (p < 0.05) and the Composipost Light-Post systems (p < 0.001). The force necessary to loosen the Para Post Fiber White specimens was significantly less than for the Composipost Light-Post system (p < 0.01). Other combinations did not differ significantly (p > 0.05).

    Conclusions: When zirconium oxide ceramic posts are luted with resin composites the bonding between the ceramic and resin composite seems to be weak. Further studies are thus necessary to achieve improved retention of all-ceramic root canal posts.

  • 186. Hedman, J
    et al.
    Sjöman, R
    Sjöström, Inger
    Twetman, Svante
    Umeå University, Faculty of Medicine, Odontology, Pediatric Dentistry.
    Fluoride concentration in saliva after consumption of a dinner meal prepared with fluoridated salt2006In: Caries Research, Vol. 40, p. 158-162Article in journal (Refereed)
    Abstract [en]

    The aim was to determine the fluoride concentration in saliva after intake of a dinner meal prepared with fluoridated salt. The investigation had a randomized cross-over design, and 10 healthy adolescents with natural fluoride content (1.06 ppm) in their drinking water participated after informed consent. After a run-in week, the subjects were served a standardized dinner of spaghetti with minced meat sauce prepared with either fluoridated salt (test arm) or non-fluoridated salt (control arm). The fluoride concentration of the test salt was 250 ppm. Samples of stimulated whole saliva was collected at baseline, directly after eating (0 min) and then after 10, 30 and 180 min. After a 1-week wash-out period, the experimental procedure was repeated with the opposite salt. Fluoride concentration in saliva was measured with a fluoride-specific electrode and the post-ingestion levels were compared with baseline using repeated-measures ANOVA.The mean baseline concentrations were 10.9 and 8.0 microg/l in the test and control arms, respectively. Immediately after the intake, the mean fluoride values increased significantly to 81.6 microg/l in the test arm and to 31.5 microg/l in the control arm (p<0.05). The fluoride levels remained elevated (p<0.05) for 30 min after ingestion of the test meal but not following the control meal. In conclusion, consumption of a dinner meal prepared with fluoridated salt increased the salivary fluoride levels for about 30 min

  • 187. Henning, Petra
    et al.
    Conaway, H. Herschel
    Lerner, Ulf H.
    Umeå University, Faculty of Medicine, Department of Odontology. Centre for Bone and Arthritis Research, Institute for Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
    Retinoid receptors in bone and their in bone remodeling2015In: Frontiers in Endocrinology, ISSN 1664-2392, E-ISSN 1664-2392, Vol. 6, article id 31Article, review/survey (Refereed)
    Abstract [en]

    Vitamin A (retinol) is a necessary and important constituent of the body which is provided by food intake of retinyl esters and carotenoids. Vitamin A is known best for being important for vision, but in addition to the eye, vitamin A is necessary in numerous other organs in the body, including the skeleton. Vitamin A is converted to an active compound, all-transretinoic acid (ATRA), which is responsible for most of its biological actions. ATRA binds to intracellular nuclear receptors called retinoic acid receptors (RAR alpha, RAR beta, RAR gamma). RARs and closely related retinoid X receptors (RXR alpha, RXR beta, RXR gamma) form heterodimers which bind to DNA and function as ligand-activated transcription factors. It has been known for many years that hypervitaminosis A promotes skeleton fragility by increasing osteoclast formation and decreasing cortical bone mass. Some epidemiological studies have suggested that increased intake of vitamin A and increased serum levels of retinoids may decrease bone mineral density and increase fracture rate, but the literature on this is not conclusive. The current review summarizes how vitamin A is taken up by the intestine, metabolized, stored in the liver, and processed to ATRA. ATRAs effects on formation and activity of osteoclasts and osteoblasts are outlined, and a summary of clinical data pertaining to vitamin A and bone is presented.

  • 188. Henningsson, Louise
    et al.
    Jirholt, Pernilla
    Bogestal, Yalda Rahpeymai
    Eneljung, Tove
    Adiels, Martin
    Lindholm, Catharina
    McInnes, Iain
    Bulfone-Paus, Silvia
    Lerner, Ulf H
    Umeå University, Faculty of Medicine, Department of Odontology, Molecular Periodontology.
    Gjertsson, Inger
    Interleukin 15 mediates joint destruction in staphylococcus aureus arthritis2012In: Journal of Infectious Diseases, ISSN 0022-1899, E-ISSN 1537-6613, Vol. 206, no 5, p. 687-696Article in journal (Refereed)
    Abstract [en]

    Background. Staphylococcus aureus arthritis causes severe and rapid joint damage despite antibiotics. Thus, there is a need to identify new treatment targets in addition to antibiotics. Lately, interleukin 15 (IL-15) has been implicated both in osteoclastogenesis and in bacterial clearance-2 important issues in S. aureus-induced joint destruction. This has prompted us to investigate the importance of IL-15 in S. aureus-induced arthritis.

    Methods.Toxic shock syndrome toxin-1 producing S. aureus was intravenously inoculated in IL-15 knockout and wildtype mice and in wildtype mice treated with anti-IL-15 antibodies (aIL-15ab) or isotype control antibody.

    Results. Absence of IL-15, either in knockout mice or after treatment with aIL-15ab, significantly reduced weight loss compared with controls during the infection. The severity of synovitis and joint destruction was significantly decreased in IL-15 knockout and aIL-15ab treated mice compared with controls. In IL-15 knockout mice there was a reduced number of osteoclasts in the joints. The host's ability to clear bacteria was not influenced in the IL-15 knockout mice, but significantly increased after treatment with aIL-15ab.

    Conclusions. IL-15 is a mediator of joint destruction in S. aureus-induced arthritis and contributes to general morbidity, which makes this cytokine an interesting treatment target in addition to conventional antibiotics.

  • 189.
    Holgerson, Pernilla L
    et al.
    Umeå University, Faculty of Medicine, Odontology, Pediatric Dentistry. Pedodonti.
    Sjöström, Inger
    Umeå University, Faculty of Medicine, Odontology, Pediatric Dentistry. Pedodonti.
    Stecksen-Blicks, Christina
    Umeå University, Faculty of Medicine, Odontology, Pediatric Dentistry. Pedodonti.
    Twetman, Svante
    Dental plaque formation and salivary mutans streptococci in schoolchildren after use of xylitol-containing chewing gum.2007In: International Journal of Paediatric Dentistry, ISSN 0960-7439, E-ISSN 1365-263X, Vol. 17, no 2, p. 79-85Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: The aim of this study was to investigate the effect of a fixed daily dose of xylitol on mutans streptococci in saliva and the amount of visible dental plaque. A second aim was to explore if the possible effects differed between children with and without caries experience. METHODS: The study was designed as a double-blind randomized controlled trial with two parallel arms. All pupils (n=149) in grades 1-6 in a comprehensive school in northern Sweden were invited, and 128 children (mean age=12.7 years) consented to participate. The children were stratified as having caries experience (DMFS/dmfs>or=1) or not before the random allocation to a test or control group. The control group (A) was given two pellets containing sorbitol and maltitol three times daily for 4 weeks, and the test group (B) received corresponding pellets with xylitol as single sweetener (total dose=6.18 g day). Clinical scoring and saliva samples were collected at baseline and immediately after the test period. The outcome measures were visible plaque index, salivary mutans streptococci counts and salivary lactic acid production. RESULTS: The amount of visible plaque was significantly reduced in both groups after 4 weeks (P<0.05). Likewise, the sucrose-induced lactic acid formation in saliva diminished in both groups (P<0.05). The proportion of mutans streptococci decreased significantly in the test group compared to baseline, but not in the control group (P<0.05). The alterations in the test group seemed most prominent among children without previous caries experience. CONCLUSIONS: The results suggest that chewing gum with xylitol or sorbitol/maltitol can reduce the amount of dental plaque and acid production in saliva in schoolchildren, but only the xylitol-containing gum may also interfere with the microbial composition.

  • 190.
    Holgerson, Pernilla L
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Vestman, Nelly R
    Umeå University, Faculty of Medicine, Department of Odontology.
    Claesson, Rolf
    Umeå University, Faculty of Medicine, Department of Odontology.
    Öhman, Carina
    Umeå University, Faculty of Medicine, Department of Odontology.
    Domellöf, Magnus
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Tanner, Anne CR
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Johansson, Ingegerd
    Umeå University, Faculty of Medicine, Department of Odontology.
    Oral microbial profile discriminates breast-fed from formula-fed infants2013In: Journal of Pediatric Gastroenterology and Nutrition - JPGN, ISSN 0277-2116, E-ISSN 1536-4801, Vol. 56, no 2, p. 127-136Article in journal (Refereed)
    Abstract [en]

    Objectives: Little is known about the effect of diet on the oral microbiota of infants, although diet is known to affect the gut microbiota. The aims of the present study were to compare the oral microbiota in breast-fed and formula-fed infants, and investigate growth inhibition of streptococci by infant-isolated lactobacilli.

    Methods: A total of 207 mothers consented to participation of their 3-month-old infants. A total of 146 (70.5%) infants were exclusively and 38 (18.4%) partially breast-fed, and 23 (11.1%) were exclusively formula-fed. Saliva from all of their infants was cultured for Lactobacillus species, with isolate identifications from 21 infants. Lactobacillus isolates were tested for their ability to suppress Streptococcus mutans and S sanguinis. Oral swabs from 73 infants were analysed by the Human Oral Microbe Identification Microarray (HOMIM) and by quantitative polymerase chain reaction for Lactobacillus gasseri.

    Results: Lactobacilli were cultured from 27.8% of exclusively and partially breast-fed infants, but not from formula-fed infants. The prevalence of 14 HOMIM-detected taxa, and total salivary lactobacilli counts differed by feeding method. Multivariate modelling of HOMIM-detected bacteria and possible confounders clustered samples from breast-fed infants separately from formula-fed infants. The microbiota of breast-fed infants differed based on vaginal or C-section delivery. Isolates of L plantarum, L gasseri, and L vaginalis inhibited growth of the cariogenic S mutans and the commensal S sanguinis: L plantarum >L gasseri >L vaginalis.

    Conclusions: The microbiota of the mouth differs between 3-month-old breast-fed and formula-fed infants. Possible mechanisms for microbial differences observed include species suppression by lactobacilli indigenous to breast milk.

  • 191.
    Holgerson, Pernilla Lif
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Sjöström, Inger
    Umeå University, Faculty of Medicine, Department of Odontology.
    Twetman, Svante
    Decreased salivary uptake of [14C]-xylitol after a four-week xylitol chewing gum regimen.2007In: Oral health and preventive dentistry, ISSN 1602-1622, Vol. 5, no 4, p. 313-319Article in journal (Refereed)
    Abstract [en]

    PURPOSE: The aims were to evaluate a simple method to disclose a microbial shift in saliva and to investigate the short- and long-term effects of daily use of xylitol-containing chewing gums on mutans streptococci (MS) and [14C]-xylitol uptake in saliva. MATERIALS AND METHODS: In a pilot set-up, saliva samples were collected from 15 healthy adults and the uptake of xylitol was compared with a specific assay determining xylitol-sensitive MS. The main study consisted of 109 schoolchildren (mean age 9.9 years) who volunteered after informed consent. The children were randomly allocated to a test or control group. The control group was given two pellets containing sorbitol and maltitol 3 times daily for 4 weeks and the test group received identical pellets with xylitol as single sweetener (total dose 6.2 g/day). Saliva samples were collected at baseline, after 4 weeks and 6 months after the intervention. The outcome measures were MS and total viable counts, proportion of MS and salivary uptake of [14C]-xylitol. RESULTS: The pilot study disclosed a fair positive correlation (p < 0.05) between the assays. The proportions of MS and salivary xylitol uptake decreased significantly in the xylitol group by 60% and 30% respectively after 4 weeks compared to baseline which was in contrast to the sorbitol/maltitol group (p < 0.05). Six months after the intervention, the outcome measures did not differ significantly from baseline in any of the groups. CONCLUSION: A relatively high daily dose of xylitol could alter salivary microbial composition during the intervention period but no long-term impact was observed.

  • 192.
    Holgerson, Pernilla Lif
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Twetman, Svante
    Stecksen-Blicks, Christina
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Validation of an age-modified caries risk assessment program (Cariogram) in preschool children.2009In: Acta Odontologica Scandinavica, ISSN 0001-6357, E-ISSN 1502-3850, Vol. 67, no 2, p. 106-112Article in journal (Refereed)
    Abstract [en]

    Objectives. (i) To validate caries risk profiles assessed with a computer program against actual caries development in preschool children, (ii) to study the possible impact of a preventive program on the risk profiles, and (iii) to compare the individual risk profiles longitudinally. Material and methods. Caries risk was assessed in 125 two-year-old children invited to participate in a 2-year caries-preventive trial with xylitol tablets. At 7 years of age, 103 were available for follow-up, 48 from the former intervention group and 55 from the control group. At baseline and after 5 years, 7 variables associated with caries were collected through clinical examinations and questionnaires, and scored and computed with a risk assessment program (Cariogram). Results. Children assessed as having a "low chance (0-20%) of avoiding caries" had significantly higher caries at 7 years of age compared to children with a lower risk in the control group (p<0.05) but not in the intervention group. Overall predictive accuracy and precision, however, were moderate in both groups. Less than half of the children remained in the same risk category at both ages, despite a largely unchanged consumption pattern of sugar. The majority of the children who changed category displayed a lowered risk at 7 years. The intervention program seemed to impair the predictive abilities of Cariogram. Conclusion. A modified Cariogram applied on preschool children was not particularly useful in identifying high caries risk patients in a low-caries community.

  • 193.
    Holm, Anna-Karin
    Umeå University, Faculty of Medicine, Department of Odontology, Pediatric Dentistry.
    Tandhälsa hos tre- till femåriga svenska barn1975Doctoral thesis, comprehensive summary (Other academic)
  • 194.
    Holm, Cecilia Koskinen
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Engman, Sara
    Umeå University, Faculty of Medicine, Department of Odontology.
    Sulniute, Rima
    Umeå University, Faculty of Medicine, Department of Odontology.
    Matozaki, Takashi
    Oldenborg, Per-Arne
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB).
    Lundberg, Pernilla
    Umeå University, Faculty of Medicine, Department of Odontology.
    Lack of SIRP alpha phosphorylation and concomitantly reduced SHP-2-PI3K-Akt2 signaling decrease osteoblast differentiation2016In: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 478, no 1, p. 268-273Article in journal (Refereed)
    Abstract [en]

    Normal differentiation of bone forming osteoblasts is a prerequisite for maintenance of skeletal health and is dependent on intricate cellular signaling pathways, including the essential transcription factor Runx2. The cell surface glycoprotein CD47 and its receptor signal regulatory protein alpha (SIRP alpha) have both been suggested to regulate bone cell differentiation. Here we investigated osteoblastic differentiation of bone marrow stromal cells from SIRP alpha mutant mice lacking the cytoplasmic signaling domain of SIRPa. An impaired osteoblastogenesis in SIRP alpha-mutant cell cultures was demonstrated by lower alkaline phosphatase activity and less mineral formation compared to wild-type cultures. This reduced osteoblastic differentiation potential in SIRPa-mutant stromal cells was associated with a significantly reduced expression of Runx2, osterix, osteocalcin, and alkaline phosphatase mRNA, as well as a reduced phosphorylation of SHP-2 and Akt2, as compared with that in wild-type stromal cells. Addition of a PI3K-inhibitor to wild-type stromal cells could mimic the impaired osteoblastogenesis seen in SIRP alpha-mutant cells. In conclusion, our data suggest that SIRPa signaling through SHP-2-PI3K-Akt2 strongly influences osteoblast differentiation from bone marrow stromal cells. 

  • 195. Holm, Charlotta
    et al.
    Tidehag, Per
    Tillberg, Anders
    Molin, Margareta
    Umeå University, Faculty of Medicine, Odontology, Prosthetic Dentistry. Umeå University, Faculty of Medicine, Odontology.
    Longevity and quality of FPDs: a retrospective study of restorations 30, 20, and 10 years after insertion.2003In: International Journal of Prosthodontics, ISSN 0893-2174, Vol. 16, no 3, p. 283-9Article in journal (Refereed)
    Abstract [en]

    PURPOSE: The aim of this retrospective study was to investigate the longevity and clinical performance of fixed partial dentures (FPD) 30, 20, and 10 years after insertion. MATERIALS AND METHODS: A total of 289 FPDs were inserted in 1966/67, 1976/77, and 1986/87. For patients with FPDs presumably still in function, an evaluation according to the CDA criteria was made. RESULTS: For 64 of the FPDs (22%), no information was available. Seventy-nine patients with 94 FPDs (33%) were clinically examined, and 44 of the FPDs (15%) were reported to be still in function by the patients' current clinicians. The remaining 87 FPDs (30%) were considered lost to follow-up. These FPDs had either been removed for various reasons--in most cases dental caries, lost retention, or fractured abutment teeth--or the patient could not be contacted. Eighty-four percent of the FPDs inserted in 1966/67 were still in function after 20 years, compared to 64% of those inserted in 1976/77. Apart from an increase in wear and discoloration, the oldest FPDs had excellent marginal fit and anatomic shape. CONCLUSION: The survival rate of 30-year-old FPDs was high; 53% remained in function after 30 years. Based on the CDA criteria, 78% of the restorations were rated satisfactory in all subgroups. The FPDs placed in 1966/67 obtained the highest ratings in color, anatomy, and margin integrity.

  • 196. Holmquist, Per
    et al.
    Dasmah, Amir
    Sennerby, Lars
    Hallman, Mats
    Umeå University, Faculty of Medicine, Department of Odontology, Oral and Maxillofacial Surgery. Clinic for Oral & Maxillofacial Surgery, Gävle Hospital, Gävle, Sweden.
    A new technique for reconstruction of the atrophied narrow alveolar crest in the maxilla using morselized impacted bone allograft and later placement of dental implants2008In: Clinical Implant Dentistry and Related Research, ISSN 1523-0899, E-ISSN 1708-8208, Vol. 10, no 2, p. 86-92Article in journal (Refereed)
    Abstract [en]

    Background: In cases when the alveolar crest is too narrow to host an implant, lateral augmentation is required. The use of autogenous bone blocks harvested from the iliac crest is often demanded. One disadvantage is the associated patient morbidity.

    Purpose: The purpose of this study was to clinically and histologically evaluate the use of morselized impacted bone allograft, a novel technique for reconstruction of the narrow alveolar crest.

    Materials and methods: Two patients with completely edentulous maxillae and one partially edentulous, with a mean age of 77 years (range 76-79 years) were included in the study. The alveolar crest width was < 3 mm without possibility to place any implant. Bone grafts were taken from a bone bank in Gavle Hospital. Bone from the neck of femur heads was milled to produce bone chips. The milled bone was partially defatted by rinsing in 37 degrees C saline solution. After compression of the graft pieces with a size of 15 mm (height), 30 mm (length), and 6 mm (width), they were then fit to adapt to the buccal surface of the atrophied alveolar crest. One piece was placed to the right and one to the left side of the midline. On both sides fibrin glue was used (Tisseel (R), Baxter AG, Vienna, Austria) to stabilize the graft. After 6 months of graft healing, dental implants were placed, simultaneously biopsies were harvested and in one patient two oxidized microimplants were placed. At the time of abutment connection, microimplants were retrieved with surrounding bone for histology. Fixed screw-retained bridges were fabricated in mean of 7 months after implant surgery. Radiographs were taken before and after implant surgery and after 1 year of loading.

    Results: Sixteen implants with an oxidized surface were placed (TiUnite (R), Nobel Biocare AB, Goteborg, Sweden). After 1 year of functional loading, all implants were clinically stable. The marginal bone loss was 1.4 mm (SD 0.3) after 1 year of loading. The histological examination showed resorption and subsequent bone formation on the allograft particles. There were no signs of inflammatory cell infiltration in conjunction with the allograft. The two microimplants showed bone formation directly on the implant surface.

    Conclusions: This study shows that morselized impacted bone allograft can be used to increase the width of the atrophied narrow alveolar crest as a good alternative to autogenous bone grafts in elderly patients. The histological examination of biopsies revealed a normal incorporation process and no signs of an immunological reaction. Further studies with larger samples are of important to be able to conclude if equal results can be obtained using morselized impacted bone allograft as for autogenous bone graft.

  • 197.
    Hulterström, Anna Karin
    Umeå University, Faculty of Medicine, Department of Odontology, Dental Technology/Dental Materials Science.
    Silicone obturators and the bacterial flora in symptomatic nasal septal perforations2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background A perforation in the nasal septum can cause symptoms such as bleeding, obstruction, crusts and pain, and can be a challenge to treat. Surgery is the treatment of choice, but disease, size of the perforation, or the patient’s wish may contradict surgery. A custom-made silicone obturator is a successful treatment option, but little is known how this treatment affects the microbial flora. The purposes of this thesis were (i) to investigate the microbial flora around symptomatic nasal septal perforations before treatment, (ii) during and after a 12-month treatment period with a custom-made obturator, (iii) to compare the microbial flora around symptomatic perforations with the flora from the same area of the septum in healthy individuals, (iv) to investigate the microbial colonization of the silicone obturator, and (v) also to investigate the water sorption, solubility and if the wettability of silicones are affected by water. The hypotheses were (i) that the bacterial flora around symptomatic perforations would not differ from that found in healthy individuals, apart from a possible presence of Helicobacter pylori; (ii) the bacterial flora would change in composition during the course of treatment and that microorganisms and proteins could be seen on the surface of the silicone obturators; (iii) a material that has adsorbed water would also show an increase in wettability and the surface free energy of the material.

     Methods Twenty-seven patients and 101 healthy individuals volunteered. Swabs were made around the rim of the perforation, or on the septum in the locus Kisselbachi area in the healthy individuals. Bacteria and fungi were isolated and identified with standard laboratory techniques. A biopsy of the granulated tissue at the perforation was taken and cultivated for Helicobacter pylori. Swabs were also taken three, six and twelve months after inserting the obturator. The obturator was analysed after being used twelve months in the nose.  Seven silicones were tested for water sorption and solubility according to ISO standards 1567:1999 and ISO 10477:2004. The change in wettability was examined by measuring the contact angle with a contact goniometer at various stages of the sorption/solubility test.

    Results Staphylococcus aureus was present in 88% of the untreated patients. With treatment a significant reduction of S. aureus occurred to 54.5% (p<0.05). In the healthy group S. aureus was present in 13% of the subjects. No Helicobacter pylori could be cultivated from the biopsies taken of the granulated tissue at the perforation. The flora round the untreated perforation was dominated by S. aureus with few other bacterial species detected. In the healthy group there was a diversified flora with both aerobic and anaerobic bacteria. SEM revealed a rough surface on the silicone obturator and crazing of the silicone surrounding the pigment granules. Both bacteria and proteins could be seen on the obturators in SEM. Candida albicans was detected in one obturator, but not in the mucosal swab at the corresponding time. That patient had, however, been treated for Candida in the nose six months prior to the last visit in the study. Wettability was affected but did not increase with amount of adsorbed water. Some materials showed an increase and some a decrease in the surface-free energy. The tested addition silicones showed little sorption and solubility.

    Conclusions The patients with symptomatic perforations of the nasal septum had a bacterial flora totally dominated by S. aureus. The massive presence of S. aureus around symptomatic perforations may have an impact on the persistence of the granulated and inflamed tissue present in symptomatic perforations, thus forming a vicious circle with bleeding and crustation.

    S. aureus dominance in the mucosa surrounding symptomatic perforations was diminished by using a custom-made obturator. The microbial flora became more diversified with the treatment, although not resembling the flora in healthy individuals. The microbial flora of the obturators was similar, but not the same as the corresponding mucosal flora. The discovery of Candida in the obturator of a patient who had been treated for Candida in the nose six months earlier suggests that obturators need to be exchanged when fungal infections are being treated to prevent the fungus from re-infecting the patient at a later stage.

    The silicone had a rough surface and a poor wettability, both aspects favours colonization of microorganisms. The silicone was negatively affected by the colouring pigments, this should be considered when colouring is not necessary. The slight, but existing solubility of silicones emphasises the importance of using medical grade silicones that are more purified than industrial silicones. 

  • 198.
    Hulterström, Anna Karin
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology, Dental Technology/Dental Materials Science.
    Berglund, Anders
    Umeå University, Faculty of Medicine, Department of Odontology, Dental Technology/Dental Materials Science.
    Ruyter, Ivar Eystein
    Wettability, water sorption and water solubility of seven silicone elastomers used for maxillofacial prostheses2008In: Journal of materials science. Materials in medicine, ISSN 0957-4530, E-ISSN 1573-4838, Vol. 19, no 1, p. 225-231Article in journal (Refereed)
    Abstract [en]

    The wettability, water sorption and solubility of silicone elastomers used for maxillofacial prostheses were studied. The hypothesis was, that a material that has absorbed water would show an increase in the wettability and thus also the surface free energy of the material.

    Seven silicone elastomers, both addition- and condensation type polymers, were included. Five specimens of each material were subjected to treatment according to ISO standards 1567:1999 and 10477: 2004 for water sorption and solubility. The volumes of the specimens were measured according to Archimedes principle. The contact angle was measured with a contact angle goniometer at various stages of the sorption/solubility test.

    Wettability changed over the test period, but not according to theory. The addition type silicones showed little or no sorption and solubility, but two of the condensation type polymers tested had a significant sorption and solubility. This study showed that condensation type polymers may show too large volumetric changes when exposed to fluids, and therefore should no longer be used in prosthetic devices. The results of this study also suggests that it might be of interest to test sorption and solubility of materials that are to be implanted, since most of the materials had some solubility.

  • 199.
    Hulterström, Anna Karin
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology, Dental Technology/Dental Materials Science.
    Sellin, Mats
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Bacteriology.
    Berggren, Diana
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    High prevalence of S. aureus around symptomatic perforations of the nasal septumManuscript (preprint) (Other academic)
  • 200.
    Hulterström, Anna Karin
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology, Dental Technology/Dental Materials Science.
    Sellin, Mats
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Bacteriology.
    Berggren, Diana
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    The effect of obturator treatment on the microbial flora surrounding symptomatic nasal septal perforationsManuscript (preprint) (Other academic)
1234567 151 - 200 of 599
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