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The association between the activity of masticatory muscles and craniofacial development has been studied in man as well as in animals. The common finding of these investigations is that the muscles closing the mandible influence the transversal closing the mandible inflkuence the transversal and the vertical dimensions of the craniofacial skeleton. The loading of the facial bones due to masticatory muscle function may stimulate sutural growth and increase bone apposition, leading in turn to an increase of the transversal growth of the maxilla and broader bone bases for the dental arches. The big functional demands of the masticatory muscles are often associated with anterior growth rotation pattern and well-developed angular, coronoid, and condylar processes in the mandible. Individuals with disabilities have an increased prevalence of malocclusion and poor oral function. Behavioural problems and deviating orofacial growth and function will complicate the orthodontic treatment. But with behavioural and various treatment modifications, we can give those patients a well adopted orthodontic treatment. That may favour the facial appearance, achieving a better mouth closure and improve the posibilities to eat and speak. The development and critical evaluation of treatment methods aiming towards normalizing craniofacial and occlusal development is essential. Modified functional appliances such as the ”mandibular repositioning appliance” (MRA) has in placebo controlled studies been shown to reduce periods of respiratory arrest and snoring in patients with mild apnea. This method may also be an alternative in more severe cases where patients do not accept treatment with continous overpressured air (CPAP). Sucessful treatment of sleep apnea must be based on a close cooperation of dentists with knowledge in this field and doctors at sleep apnea clinics. Effects and side effects of treatment must be supervised during long periods.

Although continuous positive airway pressure (CPAP) is considered to represent the standard treatment for patients with moderate-to-severe obstructive sleep apnoea/hypopnoea syndrome (OSAHS), poor treatment compliance and/or refusal is an issue in ∼20-3% of these patients.

As an alternative to life-long CPAP treatment, conservative procedures exist with dental appliances for mandibular advancement, as well as curative surgical techniques.

Surgical treatment of OSAHS can be divided into the following two main groups:

1) upper airway surgery by soft tissue resection (uvulopalatopharyngoplasty, etc.), and

2) skeletal procedures, such as maxillo-mandibular advancement. Proper selection of patients for the different treatment modalities is the key for full treatment success.

Patient-related factors, such as the site of upper airway collapse, craniofacial characteristics, dental health, obesity, age, profession and positional dependence, as well as treatment-related factors, should be evaluated before a final proposal for these treatment alternatives is formulated.

Snoring and obstructive sleep apnea form part of a spectrum of sleep disordered breathing affecting a significant proportion of the general population and particularly the middle aged. The consequences can be severe and even life threatening for both the individual directly affected and those more remotely involved. Adverse sequelae can manifest themselves acutely or in the longer term as a result of obstructive breathing induced hypersomnolence, neurocognitive deficits and cardiovascular abnormilities. The combination of anatomical and neuromuscular risk factors in the pathogenesis of OSA has resulted in a varied appoach to its management. One such treatment option is mandibular repositioning appliances (MRA), which mechanically stabilize the airway. Whilst the efficacy of this simple intervention has been rigorously proven quite recently in a significant proportion of patients with varying disease severity, individual patient selection in its application remains uncertain. Short-term side-effects are common but usually transient, whilst in the long-term minor permanent adverse developments on the dentition and occlusion have been reported. Considering both the medicolegal implications of snoring and OSA and the increasing popularity of MRA, it is recommended that skilled multidisciplinary respiratory and dental personnel form the primary care team.

CONCLUSIONS:There are gender differences when it comes to the risk factors for sleep apnea. Large tonsils, a high tongue and a wide uvula are risk factors for sleep apnea in men, while large tonsils and a retrognathic mandible are risk factors in women. Upper airway abnormalities including mandibular retrognathia are, however, unable to predict sleep apnea among snorers being investigated for suspected sleep apnea.

OBJECTIVES: To identify gender-specific risk factors for obstructive sleep apnea and the diagnostic performance from physical upper airway examinations among snoring men and women investigated because of suspected sleep apnea.

PATIENTS AND METHODS: The dimensions of the uvula, tonsils, velopharynx and tongue, and nasal septal deviation, mandibular position, neck circumference, weight, and height were systematically scored in 801 consecutive snoring patients (596 men and 205 women), who had been referred for a primary sleep apnea recording.

RESULTS: In men, large tonsils, a high tongue, and a wide uvula were independent factors associated with an apnea-hyopnea index of > 15. In women, large tonsils and mandibular retrognathia were independent factors associated with an apnea-hypopnea index of > 15. The positive predictive values for upper airway abnormalities ranged between 0.20 and 0.25 in men and between 0.09 and 0.15 in women.

Background. Studies have shown conflicting results on the association between nickel exposure from orthodontic appliances and nickel sensitization.

Objectives & Method. In a cross-sectional study, we investigated the association between nickel sensitization and exposure to orthodontic appliances and piercings. 4376 adolescents were patch tested following a questionnaire asking for earlier piercing and orthodontic treatment. Exposure to orthodontic appliances was verified in dental records.

Results. Questionnaire data demonstrated a reduced risk of nickel sensitization when orthodontic treatment preceded piercing (OR 0.46; CI 0.27–0.78). Data from dental records demonstrated similar results (OR 0.61, CI 0.36–1.02), but statistical significance was lost when adjusting for background factors. Exposure to full, fixed appliances with NiTi-containing alloys (OR 0.31, CI 0.10–0.98) as well as a pooled ‘high nickel-releasing’ appliance group (OR 0.56, CI 0.32–0.97) prior to piercing was associated with a significantly reduced risk of nickel sensitization.

Conclusion. High nickel-containing orthodontic appliances preceding piercing reduces the risk of nickel sensitization by a factor 1.5–2. The risk reduction is associated with estimated nickel release of the appliance and length of treatment. Sex, age at piercing and number of piercings are also important risk indicators. Research on the role of dental materials in the development of immunological tolerance is needed.

Major reductions in caries prevalence among children have been seen in many countries, arguing for changes in organization of annual check-ups and prophylactic procedures. The purpose of our study was to clarify whether an organization of annual oral health examinations of children in the Swedish PDHS by dental assistants or dental hygienists, without a legal right for diagnosing deviations in occlusal development, has resulted in changes in diagnosis or measures related to deviations in maxillary cuspid eruption. Dental records from 6 to 14 years of age for 1000 patients from clinics with traditional annual examinations by dentists and 999 from clinics with ”delegated” check-ups were scrutinized with regard to notes or measures related to cuspid development and eruption. A significant lower number of deviations in cuspid eruptions were reported in clinics with ”delegated” check-ups (p=0.003). A tendency for later radiological examinations was also seen in this group. Sixty patients (2.7%) had been given the diagnosis ”retained maxillary cuspid”, but with no difference in number between the two groups of clinics. A lower quality with regard to diagnosis and measures of deviations in occlusal development in delegated annual examinations of children could thus not be contradicted.

In this study, the effect of the integrated Herbst appliance (IHA) was examined in 30 Swedish males (mean age 14.2 +/- 0.96 years) with a Class II malocclusion. An evaluation of hand-wrist radiographs showed that the patients were in the maturation stages MP3-F, MP3-FG, or MP3-G at the start of treatment. The average treatment time with the Herbst mechanics was 0.7 years. Dentoskeletal and soft tissue parameters were analysed on lateral radiographic head films taken at the start and end of the IHA treatment. The pre- and post-Herbst values of a number of skeletal and dental variables in the treatment group were compared with the corresponding values in a group of untreated age-matched males with Class II malocclusions. Differences in the cephalometric measurements pre- and post-Herbst treatment were determined using paired t-tests. In general, the control group exhibited only minor or no changes during the period of observation, whereas treatment with the IHA resulted in statistically significant and favourable changes of the recorded variables. In the IHA patients, ANB angle was reduced on average by 2.1 degrees. However, a skeletal post-normality (ANB = 3.9 degrees) remained even though a Class I dental relationship had been obtained. In comparison with treatment effects achieved with other designs of Herbst appliances, some minor differences in the changes of the variables SNA and ML/NSL were noted in the present study. These differences could probably be attributed to the particular treatment protocol which was applied in the IHA treatments.

This overview summarizes current knowledge of effects, side effects and indications for oral appliances in the treatment of patients with obstructive sleep apnea (OSA) and snoring. Mandibular repositioning appliances (MRAs) in various designs represent the most evaluated type of oral appliance. MRAs relocate the lower jaw forward and downward in order to prevent sleep-induced pharyngeal collapse. Short-term success rates with MRAs of over 80% of selected OSA patients have been reported, but figures vary. MRAs are indicated for patients with mild to moderate OSA, men with supine-dependent OSA and women. Patients with initial treatment success may benefit from MRAs over a long time, provided that they do not gain weight and wear high quality devices. There are few randomized controlled trials of treatment effects from MRAs on OSA, particularly regarding symptoms. MRA design, methodology and the teamwork between dentists and physicians has an influence on the treatment outcome. Continuous positive airway presssure is the primary treatment for patients with more severe OSA because of its superior effects compared with MRAs. Another drawback of MRAs is their dependence on healthy teeth and the risk of dental side effects. It is concluded that MRAs are indicated for selected patients with OSA, but more research is needed.

Introduction: Orthodontic side effects can complicate the long-term use of mandibular advancement devices (MADs) in the treatment of patients with snoring anad obstructive sleep apnea. The aim of this study was to find predictors of dental side effects from monoblock MADs. Methods: Four hundred fifty patients, who consecutively received treatment with either soft elastomeric or hard acrylic devices, were followed up after 5.4 ± 0.8 years (mean ± SD). The continuing patients responded to questionnaires and had dental examinations and plaster casts made. Results: Twenty-seven patients had moved or died during the follow-up period. Two hundred thirty-six of the remaining 423 patients (56%) continued treatment, and 187 of them reported compliance rates of ≥50% at night. A small reduction in overjet of <1 mm was associated with a deepbite with an overbite of >3mm and an overjet of ≤3 mm (odds ratio [OR] = 7.5; P =.015), nasal congestion (OR = 2.9; P = .005), or the use of a soft elastomeric device (OR = 2.7; P = .014) controlled for age, sex, treatment time, and mandibular displacement. A small reduction in overbite of <1 mm was related to a small opening of the mandible of <11 mm (OR = 2.5; P = .008). Conclusions: Orthodontic side effects might be predictable on the basis of initial characteristics in dental occlusion and the design of MADs.

Mandibular repositioning appliances (MRAs) reduce symptoms of obstructive sleep apnoea in the short term, but the long-term effects are unknown. Our objective was to evaluate the long-term symptomatic effects of custom-made MRAs and to identify the patients who will experience subjective benefits from treatment. A cohort of 260 consecutive patients treated with appliances for non-apnoeic snoring or sleep apnoea was followed up by a questionnaire and examination after an average of 5.4 years. The subjective effect was defined as good when complaints of daytime sleepiness occurred less than once a week. A total of 185 patients (71%) responded to the questionnaires. Of the respondents, 96 reported frequent use, 33 reported infrequent use, 26 reported discontinued treatment and 30 reported modified treatment. Mild cases (apnoea-hypopnoea index [AHI] < 15) were likelier than more severe cases to continue treatment. Patients who had used MRAs reported fewer complaints of sleepiness, headaches and daytime naps. Frequent use (P = 0.001), few night-time awakenings before start of treatment (P = 0.02) and effective apnoea reduction during treatment of more severe cases (P = 0.02) correlated with a good subjective effect at long-term follow-up. Our conclusion is that custom-made MRAs reduce sleep apnoea symptoms in the long term. The mildest cases will experience the greatest long-term benefit.The reason is that non-apnoeic snorers and patients with a mild disease are more likely to continue treatment and that their long-term results with regard to excessive sleepiness are similar to patients with a more severe disease.

Objective: To evaluate the effects of a mandibular advancement device on apneas and sleep in, mild, moderate and severe obstructive sleep apnea.

Design: Prospective study.

Subjects: Forty-four of 47 patients included.

Intervention: Individually adjusted mandibular advancement devices.

Measurements: Polysomnographic sleep recordings for 1 night without the device and 1 night with it, with a median of 1 day and no changes in weight, medication, or sleep position between the recordings.

Results: The device reduced the median apnea-hypopnea index from 11 (range, 7 to 19) to 5 (range, 0 to 17) (p<0.001) in 21 patients with mild sleep apnea, from 27 (range, 20 to 38) to 7 (range 1 to 19) (p<0.001) in 15 patients with moderate sleep apnea, and from 53 (range 44 to 66) to 14 (range, 2 to 32) (p=<0.05) in 8 patients with severe sleep apnea. The arousal index decreased and the sleep stage patterns improved in all severity groups. Twenty-eight of 44 patients were successfully treated with an obstructive apnea-hypopnea index of below 10 and a subjective reduction in snoring. Nine of 16 patients with treatment failure still reported a reduction in snoring. The success rate correlated inversely to the disease severity (r=-0.41; p<0.01).

Conclusions: A mandibular advancement device reduces apnea and improves sleep quality in patients with obstructive sleep apnea, especially in those with mild and moderate disease. A follow-up sleep recording during treatment is necessary because of the risk of silent obstructive apneas without subjective snoring with the device.

OBJECTIVE: This pilot study was performed to test the hypothesis that an orthodontic oral appliance (OA) that is designed to work against the backwardly directed forces on the upper incisors may counteract the reduction in overjet from these devices.

MATERIALS AND METHODS: Thirty patients with normal bites, good oral health, and milder sleep apnea were randomized to treatment with either OAs or orthodontic OAs. Bite changes were evaluated on plaster casts and radiographs and by questionnaires after a mean of 2.4 years in 19 frequent users.

RESULTS: Four of nine patients in the orthodontic OA group increased their overjet by > or =0.4 mm, while none of the 10 patients in the OA group experienced that effect.

CONCLUSION: Only the orthodontic OA increases the overjet; this design may therefore be beneficial to patients at risk of negative effects on their bite during OA treatment.

Study objective: To evaluate the tolerability and to find predictors of treatment success for an individually adjusted, one-piece mandibular advancement device in patients with snoring and obstructive sleep apnea.

Design: Prospective study.

Setting: Departments of Respiratory Medicine and Orthodontics, Umeå University.

Patients: Six hundred nineteen of 630 patients (98%), who consecutively received treatment for sleep apnea and snoring from February 1989 to August 2000, were followed up. They had a mean apnea-hypopnea index of 16 (range, 0.0 to 76) and a mean body mass index of 28 (range, 19 to 42).

Measurements: Interviews, questionnaires, and overnight sleep apne a recordings. Patients with an apnea-hypopnea index of ≥10 in the supine and/or lateral position were considered to have obstructive sleep apnea. A lateral apnea-hypopnea index of < 10, together with a supine apnea-hypopnea index of ≥ 10, defined supine-dependent sleep apneas.

Results: One hundred forty-eight of the 619 patients (24%) discontinued treatment. Female gender predicted treatment success, defined as an apnea-hypopnea index of < 10 in both the supine and lateral positions, with an odds ratio of 2.4 (p = 0,01). In the women, the odds ratios for treatment success were 12 for mild sleep apnea (p = 0.04), and 0.1 for complaints of nasal obstruction (p = 0.03). In the men, the odds ratios for treatment success were 6.0 for supine-dependent sleep apneas (p < 0.001), 2.5 for mild sleep apnea (p = 0.04), 1.3 for each millimeter of mandibular advancement (p = 0.03), and 0.8 for each kilogram of weight increase (p = 0.001).

Conclusions: The mandibular advancement device is recommended for women with sleep apnea, for men with supine-dependent sleep apneas defined by a lateral apnea-hypopnea index of < 10, and for snorers without sleep apnea. Men who increase in weight during treatment reduce their chance of treatment success and are advised to be followed up with a new sleep apnea recording with the device.

Mandibular advancement devices (MADs) represent the main non-continuous positive airway pressure (non-CPAP) therapy for patients with obstructive sleep apnoea (OSA). The aim of the European Respiratory Society Task Force was to review the evidence in favour of MAD therapy . Effects of tongue-retaining devices are not included in this report.

 Custom-made MADs reduce apnoea/hypopnoea index (AHI) and daytime sleepness compared with placebo devices. CPAP more effectively dIminishes AHI, while increasing data suggest fairly similar outcomes in relation to symptoms and cardiovascular health from these treatments. Patients often prefer MADs to CPAP. Milder  cases and patients with a proven increase in upper airway size as a result of mandibular advancement are most likely to experience treatment success with MADs. A custom-made device titrated from an initial 50% of  maximum mandibular  advancement has been recommended. More research is needed to define the patients who will benefit from MAD treatment compared with CPAP, in terms of the effects on sleep—disordered breathing and on other diseases related to OSA.

 In conclusion,  MADs are recommended for patients with mild to moderate OSA (Recommendation Level A) and for those who do not tolerate CPAP. The treatment must be followed up and the device adjusted or exchanged in relation to the outcome.

Objectives To systematically investigate the biological interface of Bio-Oss by analysing dissolution–precipitation behaviour and osteogenic responses using in vitro experimental systems.

Material and methods Different concentrations (1–100 mg/ml) of Bio-Oss were incubated in cell culture medium for 24 h before elemental concentrations for calcium, phosphorus and silicon in the medium were analysed with inductive coupled plasma-optical emission spectroscopy. Radioactive calcium-45 isotope labelling technique was used to study possible precipitation of calcium on the Bio-Oss particle. Biological interface of Bio-Oss was studied in osteogenic experiments using mineralization medium and three different sources of cells (primary mouse bone marrow stromal cells, primary rat calvarial cells and MC3T3-E1 mouse pre-osteoblast cell line). Cells were fixed and stained with Toulidine blue, von Kossa or Alizarin Red staining for confirmation of extracellular matrix mineralization.

Results Elemental analysis of the cell culture medium demonstrated a significant decrease of calcium and phosphorus and a dose-dependent release of silicon to the medium after incubation with Bio-Oss. A significant decrease of calcium and phosphorus in the medium occurred even at low concentrations of Bio-Oss. Uptake of calcium on the Bio-Oss particle was confirmed with radioactive calcium-45 isotope labelling technique. In osteogenic experiments with Bio-Oss (<1 mg/ml), matrix mineralization around the Bio-Oss particles were demonstrated in all three cell types with von Kossa and Alizarin Red staining.

Conclusion Dissolution–precipitation reactions occur at the surface of Bio-Oss, and osteogenic responses are seen at the biological interface. The concentration of Bio-Oss is a key factor for the experimental in vitro results, and may also have implications for the clinic.

Three bone graft substitute materials (Bioglass 45S5, Bio-Oss (R) and Algipore (R)) were conditioned in a-minimum essential medium (alpha-MEM), with the addition of 10% fetal bovine serum (FBS), for 1 and 7?days. The chemistry of their solid-solution interface was monitored by X-ray photoelectron spectroscopy, using fast-frozen sample technique, and compared to that reported for original alpha-MEM. FBS added to the biological medium causes significant changes in the interface after only 1day of conditioning. Interfacial chemical composition and N 1s spectra show immediate adsorption of proteins at the surface of all three biomaterials, independent of their surface charge and chemical composition. However, the atomic ratio C/N and the C 1s spectra indicate a different orientation of adsorbed serum proteins, which is dependent on the particle's surface charge. Moreover, the adsorption of serum proteins at the surface of Bio-Oss causes a charge reversal at the interface, as evidenced by the change in the atomic ratio of Na/Cl. In addition to the particle's surface charge, the formation of the protein interfacial layer at the surface of the biomaterial seems to be the second major phenomenon important for subsequent cell recognition and the initiation of biomineralization. Copyright (c) 2012 John Wiley & Sons, Ltd.

Rationale: The efficacy of immediate adaptation of mandibular advancement devices made of thermoplastic material as a treatment option for sleep-disordered breathing (SDB) has been demonstrated in clinical studies. To date, there have been no studies comparing the efficacy of such prefabricated devices with custom-made devices.

Objectives: Our purpose was to compare the efficacy of both types of devices in patients with SDB.

Methods: A randomized controlled cross-over trial, comprising 4 months of treatment with a thermoplastic and a custom-made device, with a 1-month washout interval.

Measurements and Main Results: A total of 35 patients (29 males; age, 49 ± 9 yr; apnea–hypopnea index [AHI], 13 ± 11 events/h; body mass index, 28 ± 4 kg/m²) completed the protocol. AHI was only reduced with the custom-madedevice (P = 0.005). In addition, this device reduced snoring to a greater extent than the thermoplastic device. The success rate was higher with the custom-made device (60 vs. 31%; P = 0.02). One-third of the patients demonstrated compliance failure with the thermoplastic device, mainly because of insufficient overnight retention. Total failure rate with the thermoplastic device was 69%, whereas the majority (63%) of these were successfully treated with the custom-made device. At the end of the study, 82% of the patients preferred the custom-made device, and 9% had no preference (P < 0.0001).

Conclusions: In this study, a custom-made device turned out to be more effective than a thermoplastic device in the treatment of SDB. Our results suggest that the thermoplastic device cannot be recommended as a therapeutic option nor can it be used as a screening tool to find good candidates for mandibular advancement therapy.