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Background: This study aimed to evaluate the effect of bioactive composite (ACTIVA) on enamel demineralisation when used as an orthodontic adhesive, compared to other adhesives.

Materials and methods: Human upper premolars (n=64) were randomly divided into two equal groups; the first group stored the bonded teeth in deionised water for 30 days at 37°C, and the second group exposed the bonded teeth to acidic media. Each group was further subdivided into four subgroups, with eight premolars in each subgroup, based on the type of adhesive used to bond metal brackets: non-fluoride-releasing adhesive (Transbond XT), fluoride-releasing adhesive (Light Bond), light-cured, resin-reinforced glass ionomer (GC Fuji ortho LC), and bioactive restorative composite (ACTIVA BioACTIVE-RESTORATIVE). Enamel demineralisation was assessed at baseline and after 30 days with a laser fluorescence device (DIAGNOdent™ Pen).

Results: There were significant differences in fluorescence variation values (ΔFV) among all four tested adhesive systems in both water and acid groups after 30 days. Light Bond adhesive showed the highest fluorescence variation value, while glass ionomer showed the lowest, indicating less enamel demineralisation around the bracket. ACTIVA had less enamel demineralisation in acidic media. However, there was no significant difference in enamel demineralisation between water storage and acidic media groups.

Conclusion: ACTIVA (RMGIC + composite) exhibited less enamel demineralisation than Light Bond; however, Fuji ortho LC showed the lowest enamel demineralisation.

Purpose: The aim was to assess skeletal stability after maxillary advancement using either distraction osteogenesis (DO) or conventional Le Fort I osteotomy (CO) in patients with cleft lip and palate (CLP) or cleft palate (CP) utilising a new superimposition-based cephalometric method.

Method: This retrospective study included patients who were treated with DO (N = 12) or CO (N = 9). Sagittal and vertical changes after surgery, and skeletal stability at 18 months post-operatively were assessed with superimposition-based cephalometry, comparing lateral cephalograms performed pre-operatively (T0), post-operatively after CO or immediately after completed distraction in DO (T1), and at 18 months of follow-up (T2).

Results: The mean sagittal movements from T0 to T2 in the DO and CO groups were 5.9 mm and 2.2 mm, respectively, with a skeletal relapse rate of 16% in the DO group and 15% in the CO group between T1 and T2. The vertical mean movement from T0 to T2 in the DO and CO groups was 2.8 mm and 2.0 mm, respectively, and the skeletal relapse rate between T1 and T2 was 36% in the DO group and 32% in the CO group.

Conclusion: Sagittal advancement of the maxilla was stable, in contrast to the vertical downward movement, which showed more-extensive relapse in both groups. Despite more-extensive maxillary advancement in the DO group, the rates of skeletal relapse were similar.

Background: Foetal alcohol spectrum disorders (FASD) include somatic and neurological developmental disturbances after prenatal alcohol exposure, including facial anomalies. However, the knowledge of the orthodontic skeletal and dental cephalometric relations in this group is limited. The aim of the study was to assess the dentofacial characteristics of children and adolescents with FASD and to compare them with a matched control group.

Methods: The study group comprised all available children and adolescents diagnosed with FASD (> 7 years of age) in whom good quality cephalograms were available. The control group comprised non-syndromic, orthodontically untreated children with normal occlusion and skeletal relations matched with age and gender. Cephalometric analysis included eighteen linear and angular measurements. The general linear model for repeated measures regarding age, gender and the type of FASD was applied.

Results: The group with FASD included 35 individuals (21 girls and 14 boys) aged 7–18 years including 21 with foetal alcohol syndrome. The mean age in the study and the control group was 12.8 years (SD, range 3.2, 7.1–18.1) and 13.0 (SD, range 2.9, 9.1–18.1), respectively. Statistically significant differences between the groups were found in 15 out of 18 of the cephalometric measurements (83%). In children with FASD the mandible was more retrusive, the incisors were more proclined and the mandibular incisors and the lips were more protruded when compared with controls. There was no significant evidence of an influence of age, gender or FASD type.

Conclusions: Dentofacial characteristics of children and adolescents with FASD significantly differ from controls. Early orthodontic diagnosis and prophylaxis should play a part of the interdisciplinary care of patients in this group.

Background: The long-term effects on dentofacial morphology of interceptive treatment with premolar extractions, in the absence of subsequent orthodontic treatment, have not been fully explored.

Objective: The aim was to investigate the effects of premolar extractions (without subsequent orthodontic treatment) on the dentoskeletal and soft tissue profile of patients aged between 12 and 62 years with Class I malocclusion with severe crowding, as compared to untreated controls.

Materials and methods: The Extraction group (N = 30 with Class I crowding malocclusion) had their first premolars removed in early adolescence without subsequent orthodontic treatment. The Control group included 30 untreated subjects with Class I normal occlusion. Cephalograms were taken at 12 (T1), 15 (T2), 30 (T3), and 62 (T4) years of age. A superimposition-based cephalometric method was used to assess the dentoskeletal and soft tissue changes.

Results: There were no significant differences between the Extraction and Control groups in terms of skeletal sagittal relation, incisor inclination, and protrusion, or most of the soft tissue parameters throughout the observation period. However, significant differences were observed between the groups with respect to the vertical relations in T2-T3, such that the Extraction group showed more-pronounced decreases in the ML/NSL, ML/NL, and Gonial angles and more-pronounced increases in facial heights.

Conclusions and implications: Treatment for subjects with Class I malocclusion with severe crowding by the extraction of four premolars, without subsequent orthodontic treatment, does not affect the long-term dentoskeletal and soft tissue profile, as compared to an untreated Control group. The degree of crowding, rather than changes in dentofacial morphology, is crucial in deciding on extraction therapy.

Background: In long-term studies of orthodontic, orthognathic, and prosthodontic treatments, control subjects are needed for comparison.

Objectives: To study the craniofacial (skeletal, soft tissue, and dental) changes that occur in untreated subjects with normal occlusion between13 and 62 years of age.

Materials/Methods: Thirty subjects with a Class I normal occlusion and harmonious facial profle were studied. X-ray examinations were performed at 13 (T1), 16 (T2), 31 (T3), and 62 (T4) years of age, and data were obtained from cephalograms. In total, 53 angular and linear parameters were measured using superimposition-based and conventional cephalometric methods to describe the craniofacial changes.

Results: The jaws showed signifcant anterior growth from T1 to T2, and signifcant retrognathism from T3 to T4. The anterior face height andjaw dimensions increased signifcantly until T3. Signifcant posterior rotation of the mandible and opening of the vertical jaw relation, in additionto signifcant retroclination of the incisors and straightening of the facial profle, were found from T3 to T4.Limitations: Given the small sample size at T4, it was not possible to analyse the gender dimension.

Conclusions/Implications: Craniofacial changes continue up to the sixth decade of life. These changes are consistent, albeit to a lesser extent,with the adolescent growth patterns for most of the studied parameters, with the exceptions of incisor inclination, sagittal jaw position, verticaljaw relation and inclination, and posterior face height.

Objectives: Study I: To evaluate the reliability and validity of different superimposition methods and to increase the precision with which craniofacial growth and treatment can be quantified. Study II: To explore the craniofacial changes that occur from early adolescence to late adulthood. Study III: To assess the impact of premolar extractions on dentoskeletal and facial morphologies up to late adulthood. Study IV: In a 50-year follow-up, to study how early extraction of four premolars affects the development of age-related lower incisor crowding. 

Materials and Methods: Study I: Forty pairs of cephalograms were analysed at mean ages of 9.9 (T1) and 15.0 (T2) years. Three superimposition methods were assessed: the Sella-Nasion (SN); the Tuberculum Sella-Wing (TW); and Björk’s structural. Björk’s structural method was performed using three techniques: direct, tracing template, and subtraction. Study II: Thirty subjects with a Class I normal occlusion and harmonious facial profile were investigated. Study data were obtained from cephalograms performed at 12 (T1), 15 (T2), 30 (T3), and 62 (T4) years of age. The craniofacial changes were assessed using superimposition-based and conventional cephalometric methods. Study III: Two groups were included. The Extraction group (N=30 with Class I crowding malocclusion) had their first premolars extracted at a mean age of 11.5 years, without subsequent orthodontic treatment. The Control group included 30 untreated subjects with Class I normal occlusion. Study data were obtained from cephalograms performed at 12 (T1), 15 (T2), 30 (T3) and 62 (T4) years of age. The dentoskeletal and soft tissue changes were assessed using superimposition-based and conventional cephalometric methods. Study IV: Two groups were included. The Extraction group (N=24 with Class I crowding malocclusion) that had their first premolars extracted at mean age of 11.5 years, without subsequent orthodontic treatment. The Control group included 21 untreated subjects with Class I normal occlusion. Study data were obtained from dental casts and cephalograms performed at mean ages of 11.4 and 13.0 years, for the two groups, respectively (T1), and at mean ages of 30.9 years (T2) and 61.7 years (T3).

Results: Study I: The numerical data from the superimposition-based cephalometrics reflected a graphical illustration of superimposition and differed significantly from the data acquired using conventional cephalometrics. While there were no significant differences between the TW method and Björk’s three techniques, significant differences were found between the SN method and the other methods. Study II: The maxilla and mandible showed significant anterior growth from T1 to T2, and significant retrognathism from T3 to T4. The anterior facial height and jaw dimensions increased significantly until T3. From T3 to T4, significant posterior rotation of the mandible and opening of the vertical jaw relation were observed, in addition to significant retroclination of the upper incisors, decrease in lip prominence, and straightening of the facial profile. Study III: There were no significant differences between the Extraction and Control groups in terms of the skeletal sagittal relation, incisor inclination and protrusion (or for most of the soft tissue parameters) during the observation period. Study IV: The Extraction group showed significant improvement in the space deficiency of the lower teeth and no changes in the irregularity of the lower incisors up to late adulthood. In contrast, both the space deficiency of the lower teeth and irregularity of the lower incisors were significantly exacerbated in the Control group, up to late adulthood. 

Conclusions: The superimposition-based cephalometric method accurately generates numerical data for the craniofacial changes. Superimposition using the TW method is valid, reliable, and feasible, and is recommended to be used for superimposition-based cephalometrics. Moreover, craniofacial changes and development of lower incisor irregularity and crowding continue up to late adulthood in untreated subjects who were originally classified as having normal occlusion. For successful long-term outcomes, clinicians should therefore consider age-related changes in patients when planning for orthodontic, orthognathic, and prosthodontic treatments. Treatment with the extraction of four premolars alone in patients with Class I malocclusion with severe crowding does not impact the long-term dentoskeletal and soft tissue profile, and results in unchanged lower incisor alignment.

Objectives: To study the effects of extraction of four premolars, without subsequent orthodontic treatment, on the crowding of lower incisors in subjects between early adolescence and late adulthood, as compared to untreated subjects.

Materials and methods: A total of 45 subjects were included in this study. The extraction group comprised 24 subjects who had all the first premolars removed at a mean age of 11.5 years, to relieve crowding in a class I malocclusion without subsequent orthodontic treatment. The control group had 21 untreated subjects, having a normal occlusion at a mean age of 13.0 years. The participants were documented with dental casts and cephalograms at mean ages of 11.4 and 13.0 years, for the two groups respectively (T1), and at mean ages of 30.9 years (T2) and 61.7 years (T3). Changes in lower incisor crowding were described as changes in “irregularity” and “space deficiency.”

Results: The extraction group showed no changes in the irregularity of the lower incisors and significant improvement of the space deficiency of the lower teeth into late adulthood. While in the control group, both irregularity of the lower incisors and space deficiency of the lower teeth increased significantly into late adulthood.

Conclusion: Lower incisor alignment remains mainly unchanged into late adulthood in subjects who have all their first premolars removed in childhood, as the only treatment to relieve teeth crowding.

Clinical relevance: Severe crowding in a class I occlusion can be solved solely with premolar extraction, allowing for spontaneous adjustments with more stable incisor alignment up to late adulthood.

To assess the craniofacial changes related to growth and/or to orthodontic and orthognathic treatments, it is necessary to superimpose serial radiographs on stable structures. However, conventional superimposition provides only a graphical illustration of these changes. To increase the precision of growth and treatment evaluations, it is desirable to quantitate these craniofacial changes. The aims of this study were to (1) evaluate a superimposition-based cephalometric method to process numerical data for craniofacial growth changes and (2) identify a valid, reliable, and feasible method for superimposition. Forty pairs of cephalograms were analyzed at T1 and T2 (mean age 9.9 and 15.0 years, respectively). The superimposition-based cephalometric method involved relating the sagittal and vertical measurements on the T2 radiographs to the nasion and sella landmarks on the T1 radiographs. Validity and reliability were evaluated for three superimposition methods: the sella-nasion (SN); the tuberculum sella-wing (TW); and Björk’s structural. Superimposition-based cephalometrics can be used to quantify craniofacial changes digitally. The numerical data from the superimposition-based cephalometrics reflected a graphical illustration of superimposition and differed significantly from the data acquired through conventional cephalometrics. Superimposition using the TW method is recommended as it is valid, reliable, and feasible.

Objective: To evaluate the effects of rapid maxillary expansion (RME) on nocturnal enuresis (NE) related to the nasal airway, nasal breathing, and plasma osmolality (as an indicator for antidiuretic hormone).

Materials and Methods: Nineteen patients with monosymptomatic primary NE, aged 6-15 years, were treated with RME for 10-15 days. To exclude a placebo effect of the RME appliance, seven patients were first treated with a passive appliance. Computed tomography of nasal cavity, rhinomanometric, and plasma osmolality measurements were made 2-3 days before and 2-3 months after the RME period. RME effects on NE were followed for three more years.

Results: Two to three months after the expansion there were significant improvements in the breathing function and a decrease in the plasma osmolality. NE decreased significantly in all patients after the RME period, and all patients showed full dryness after 3 years.

Conclusions: This study demonstrates that RME causes complete dryness in all patients, with significant effects on pathophysiological mechanisms related to NE.