Response to letter to the Editor: Look at the elephant! Commentary on 'Prevalence of temporomandibular disorders in adult obstructive sleep apnoea patients: A cross-sectional controlled study'.

Obstructive sleep apnoea and temporomandibular disorders are complex pathologies. Considering dento-skeletal occlusion as their main predisposing factor could be detrimental for optimal patient care.

Online information on mandibular advancement device for the treatment of obstructive sleep apnea: A content, quality and readability analysis.

BACKGROUND: Despite increasing scientific interest in the effectiveness of mandibular advancement device (MAD) for the treatment of obstructive sleep apnoea (OSA), laypeople lack knowledge about this treatment option. OBJECTIVES: To investigate content, quality and readability of the online information regarding MAD. METHODS: Google, Yahoo and Bing were searched for 'sleep apnea', 'mandibular advancement device' and 'oral appliance'. Websites were analysed for content (multidisciplinary care team, qualified dentist, treatment contraindications and side effects), as well as for quality (DISCERN instrument, HONcode) and readability scores (Flesch Reading Ease, FRE and Flesch-Kincaid Reading Grade, FKG). RESULTS: Totally, 155 websites were included: 53% from health professionals, 20% commercial, 17% academic and 10% from non-health professionals. Content was incomplete, especially for commercial ones. 71.61% websites failed to acknowledge treatment contraindications, approximately 40.00% did not mention side effects and the need for a multidisciplinary care team, while 22.58% did not address the need to consult a qualified dentist. Quality and reliability were poor. Mean DISCERN score was 39.93 (95% CI 37.90-41.96), with lower scores for commercial websites compared with others. Only nine websites displayed HONcode certification. Readability was quite difficult, with mean FRE score of 59.50 (95% CI 57.58-61.42) and mean FKG level of 6.92 (95% CI 6.64-7.21). CONCLUSION: Health care professionals should be aware that currently available online information do not fulfil the most important aspects of MAD therapy and may be difficult to understand by laypeople. This could contribute to cause delays in appropriate OSA care and unrealistic treatment expectations, increasing the risk of treatment discontinuation.

Prevalence of temporomandibular disorders in adult obstructive sleep apnoea patients: A cross-sectional controlled study.

BACKGROUND: Obstructive sleep apnoea (OSA) is characterised by partial or complete obstruction of the upper airways during sleep and it has been associated with temporomandibular disorders (TMDs) on the basis of several pathophysiological hypotheses. OBJECTIVES: To assess the prevalence of TMDs in a population of patients affected by OSA compared to a control group of subjects not affected by OSA. METHODS: A cross-sectional controlled study was conducted on a group subjects studied by polygraphy (PG) at the snoring section of the ENT department, Sant'Orsola-Malpighi Hospital - University of Bologna. Patients who received a diagnosis of OSA were included in the study group and subjects with a negative PG diagnosis for Sleep Disordered Breathing and PG respiratory pattern that did not suggest the occurrence of sleep disorders were enrolled in the control group. Both the subjects included in the study group and the control group underwent an examination following the Diagnostic Criteria for Temporomandibular Disorders Axis I and II. RESULTS: Forty-three OSA patients (29 M, 16 F, mean age 52.26 ± 11.40) and 43 healthy controls (25 M, 18 F, mean age 49.95 ± 7.59) were included in the study. No significant differences were found between groups in demographic data. TMD prevalence and Axis II results did not differ between groups. CONCLUSIONS: This paper does not highlight a higher prevalence of TMDs in adults with OSA compared to healthy controls. Further high-quality studies are needed to confirm the results and to give possible pathophysiological explanations, providing reliable evidence.

Dropout and adherence of obstructive sleep apnoea patients to mandibular advancement device therapy: A systematic review of randomised controlled trials with meta-analysis and meta-regression.

BACKGROUND: Mandibular advancement devices (MADs) are used as an alternative to continuous positive airways pressure to treat obstructive sleep apnoea (OSA) patients, but to date, specific data on the adherence to MAD therapy are lacking. OBJECTIVES: The aim of the present systematic review was to investigate the dropout rate and adherence of OSA patients to different custom-made (CM) and non-custom-made (NCM) MAD therapies. SEARCH METHODS: An electronic search was performed in MEDLINE, Cochrane Database of Systematic Reviews, Scopus, LILACS and Web of Science. SELECTION CRITERIA: Randomised controlled trials (RCTs) assessing the compliance to customised and not customised MADs in the treatment of adult OSA patients were included. DATA COLLECTION AND ANALYSIS: The quality of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) and the risk of bias by the Cochrane Collaboration's tool for assessing risk of bias in RCT. The dropout rate of each study was computed and the adherence to MAD therapy in terms of hours per night and nights per week was extracted from each study. RESULTS: Thirty-two RCTs were included. The risk of bias resulted low in most of the studies. The GRADE scores indicated that the quality of evidence was from very low to moderate. The meta-analyses showed that the mean dropout rate did not significantly differ between CM and NCM MADs: The overall mean dropout rate was 0.171 [0.128-0.213] with a mean follow-up of 4.1 months. The hours per night adherence was significantly higher for CM MADs (6.418 [6.033-6.803]) compared to NCM MADs (5.107 [4.324-5.890]. The meta-regression showed that the dropout rate increases significantly during time (p < .05). CONCLUSIONS: There is a very low to moderate quality of evidence that the dropout rate of MAD therapy is similar among CM and NCM MADs, that the dropout rate increases significantly during time and that CM MADs have higher hours per night adherence compared with NCM MAD. REGISTRATION: The study protocol was registered on PROSPERO (n. CRD42020199866).

Obstructive sleep apneas naturally occur in mice during REM sleep and are highly prevalent in a mouse model of Down syndrome.

STUDY OBJECTIVES: The use of mouse models in sleep apnea study is limited by the belief that central (CSA) but not obstructive sleep apneas (OSA) occur in rodents. We aimed to develop a protocol to investigate the presence of OSAs in wild-type mice and, then, to apply it to a validated model of Down syndrome (Ts65Dn), a human pathology characterized by a high incidence of OSAs. METHODS: In a pilot study, nine C57BL/6J wild-type mice were implanted with electrodes for electroencephalography (EEG), neck electromyography (nEMG), and diaphragmatic activity (DIA), and then placed in a whole-body-plethysmographic (WBP) chamber for 8 h during the rest (light) phase to simultaneously record sleep and breathing activity. CSA and OSA were discriminated on the basis of WBP and DIA signals recorded simultaneously. The same protocol was then applied to 12 Ts65Dn mice and 14 euploid controls. RESULTS: OSAs represented about half of the apneic events recorded during rapid-eye-movement-sleep (REMS) in each experimental group, while the majority of CSAs were found during non-rapid eye movement sleep. Compared with euploid controls, Ts65Dn mice had a similar total occurrence rate of apneic events during sleep, but a significantly higher occurrence rate of OSAs during REMS, and a significantly lower occurrence rate of CSAs during NREMS. CONCLUSIONS: Mice physiologically exhibit both CSAs and OSAs. The latter appear almost exclusively during REMS, and are highly prevalent in Ts65Dn. Mice may, thus, represent a useful model to accelerate the understanding of the pathophysiology and genetics of sleep-disordered breathing and to help the development of new therapies.

Effectiveness of different mandibular advancement device designs in obstructive sleep apnoea therapy: A systematic review of randomised controlled trials with meta-analysis.

Mandibular advancement devices (MADs) are used to treat patients with obstructive sleep apnoea (OSA). To date, there are no data that identify the most effective MAD design for apnoea-hypopnea index (AHI) reduction. The purpose of this systematic review is to investigate the effectiveness of different MAD designs in AHI reduction and oxygen saturation improvement in OSA patients. An electronic search was performed in MEDLINE, Cochrane Database, Scopus, Web of Knowledge and LILACS. Randomised controlled trials (RCTs) investigating the reduction of AHI on adult patients wearing MAD for OSA were included. The quality of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) and the risk of bias by the Cochrane Collaboration's tool for assessing risk of bias in randomised controlled trial. The success rate of each study was computed: [(mean baseline AHI - mean AHI after treatment)/mean baseline AHI]. Fifty RCTs were included. The risk of bias resulted with some concerns in most of the studies. The GRADE scores indicated that the quality of evidence was very low. The meta-analysis showed a success rate with mono-bloc and duo-bloc MADs respectively of 0.821 [0.722-0.887] and 0.547 [0.443-0.637]. The mono-bloc compared with duo-bloc better improved the minimum oxygen saturation (10.048 [7.733-12.363] and 3.357 [2.290-4.423], respectively). There is a very low quality body of evidence that mono-bloc MADs are more effective in reducing AHI and improving minimum oxygen saturation compared with duo-bloc MADs. The study protocol was registered on PROSPERO (n. CRD42019118084).

Evidence from systematic reviews on photobiomodulation of human bone and stromal cells: Where do we stand?

This study summarizes the available evidence from systematic reviews on the in vitro effects of photobiomodulation on the proliferation and differentiation of human bone and stromal cells by appraising their methodological quality. Improvements for future studies are also highlighted, with particular emphasis on in vitro protocols and cell-related characteristics. Six reviews using explicit eligibility criteria and methods selected in order to minimize bias were included. There was no compelling evidence on the cellular mechanisms of action or treatment parameters of photobiomodulation; compliance with quality assessment was poor. A rigorous description of laser parameters (wavelength, power, beam spot size, power density, energy density, repetition rate, pulse duration or duty cycle, exposure duration, frequency of treatments, and total radiant energy), exposure conditions (methods to ensure a uniform irradiation and to avoid cross-irradiation, laser-cell culture surface distance, lid presence during irradiation) and cell-related characteristics (cell type or line, isolation and culture conditions, donor-related factors where applicable, tissue source, cell phenotype, cell density, number of cell passages in culture) should be included among eligibility criteria for study inclusion. These methodological improvements will maximize the contribution of in vitro studies on the effects of photobiomodulation on human bone and stromal cells to evidence-based translational research.

Effect of Chitosan as a Cross-Linker on Matrix Metalloproteinase Activity and Bond Stability with Different Adhesive Systems.

The aim of the present study was to evaluate the effect of 0.1% chitosan (Ch) solution as an additional primer on the mechanical durability and enzymatic activity on dentine using an etch-and-rinse (E&R) adhesive and a universal self-etch (SE) adhesive. Microtensile bond strength and interfacial nanoleakage expression of the bonded interfaces for all adhesives (with or without pretreatment with 0.1% Ch solution for 1 min and air-dried for 5 seconds) were analyzed immediately and after 10,000 thermocycles. Zymograms of protein extracts from human dentine powder incubated with Optibond FL and Scotchbond Universal on untreated or Ch-treated dentine were obtained to examine dentine matrix metalloproteinase (MMP) activities. The use of 0.1% Ch solution as an additional primer in conjunction with the E&R or SE adhesive did not appear to have influenced the immediate bond strength (T0) or bond strength after thermocycling (T1). Zymography showed a reduction in MMP activities only for mineralized and demineralized dentine powder after the application of Ch. Application of 0.1% Ch solution does not increase the longevity of resin-dentine bonds. Nonetheless, the procedure appears to be proficient in reducing dentine MMP activities within groups without adhesive treatments. Further studies are required to comprehend the cross-linking of Ch with dentine collagen.

Maximum voluntary retrusion or habitual bite position for mandibular advancement assessment in the treatment of obstructive sleep apnoea patients.

BACKGROUND: There is no consensus on whether the range of mandibular advancement for the construction of mandibular advancement devices in obstructive sleep apnoea (OSA) patients should be measured from a starting position of maximum voluntary retrusion or habitual bite position. OBJECTIVE: The purposes of this study were to investigate the differences in mandibular advancement registrations starting from maximum voluntary retrusion or from habitual bite position and to evaluate the reliability of these assessments. METHODS: A retrospective cohort analysis of 126 patients with OSA was performed. All patients had their mandibular range of motion evaluated twice (starting from maximum voluntary retrusion and from habitual bite position) through the George Gauge before undergoing drug-induced sleep endoscopy. The Dahlberg formula and paired t test were used to calculate random and systematic errors of dental positions assessment. Test-retest reliability was quantified using the intra-class correlation coefficient (ICC). RESULTS: The mean mandibular range starting from maximum voluntary retrusion and from habitual bite position were 12.49 ± 2.19 mm and 7.68 ± 2.29 mm, respectively, with a mean distance between the two starting positions of 4.81 ± 1.75 mm. No systematic error was found (P > .05), and random errors ranged from 0.30 to 0.95 mm. ICC values were excellent for maximum voluntary protrusion (ICC = 0.986) and maximum voluntary retrusion (ICC = 0.956), whereas habitual bite position showed a good value (ICC = 0.818). CONCLUSION: The difference between maximum voluntary retrusion and habitual bite position is potentially relevant. Maximum retrusion is advisable as starting point of the mandibular advancement registration since it provides a more reliable measure.

Short-term effects of the Sander bite-jumping appliance on the pharyngeal airways in subjects with skeletal Class II malocclusion: A retrospective case-control study.

BACKGROUND: Skeletal Class II subjects present often a retruded mandible that might increase the probability of breathing disorders. OBJECTIVE: To evaluate the effects of functional treatment by means of the Sander bite-jumping appliance (BJA) on the upper airways of growing subjects. METHODS: Thirty-four subjects (21 males, 13 females; mean age 11.1 ± 1.2 years) with skeletal Class II malocclusion due to mandibular retrusion were treated with the Sander BJA (BJA group). The control group consisted of thirty-four untreated subjects with skeletal Class II malocclusion (25 males, 9 females; 10.4 ± 1.2 years; CTR group). The effect of the Sander BJA appliance on the airway dimensions was evaluated by comparing lateral cephalograms recorded before (T0) and after (T1) the period of observation/treatment. Within- and between-group comparisons were statistically evaluated according to the distribution of the data (P < .05). RESULTS: The oropharyngeal region (ph_pph) increased in the BJA group (1.8 ± 3.2; P = .001) but the difference respect to the CTR group was not statistically significant (0.73 ± 4.0; P = .314; P = .077). The tongue height (th) increased in the BJA group (2.8 ± 3.7; P < .001), and this increase was statistically significant respect to the CTR group (0.6 ± 4.7; P = .461; P = .038). In the BJA, the Ans_Pns_P angle showed a statistically significant decrease (-3.8 ± 7.8; P = .007) compared to the CTR group (-0.1 ± 5.4; P = .705; P = .026). CONCLUSIONS: The airway dimensions increased for both control subjects and Class II patients treated with Sander BJA due to physiological growth. The Sander BJA induced a statistically significant change in the tongue and soft palate position, but the clinically relevant of these changes is questionable.

The effectiveness of mandibular advancement devices in the treatment of obstructive sleep apnoea in adults: a methodological quality assessment of systematic reviews.

BACKGROUND AND OBJECTIVES: There is growing interest in the use of mandibular advancement devices (MADs) for the treatment of obstructive sleep apnoea (OSA). Many systematic reviews (SRs) have investigated their effectiveness, but the applicability of SR results is affected by their methodological quality. This study critically appraises the methodological quality of SRs on this topic using a more detailed and updated version of A MeaSurement Tool to Assess systematic Reviews (AMSTAR). MATERIALS AND METHODS: The literature was searched for SRs on MAD effectiveness in adults (≥18 years of age) for OSA treatment as compared with other non-surgical or surgical interventions or no intervention. Any objective or subjective measures of treatment outcome were considered eligible. AMSTAR2 was used to assess methodological quality. RESULTS: The literature search yielded 64 potential reports; 10 met the eligibility criteria. All SRs had more than one critical flaw in AMSTAR2, so their methodological quality was rated as critically low. The most common issues included non-registration of study protocol, absence of list of excluded studies, no acknowledgment of fundings of included studies, no impact of risk of bias on SR results or interpretation and discussion of results, and data extraction not in duplicate. LIMITATIONS: If a SR was not clearly identified by title or abstract as a SR or meta-analysis, it may have been missed during the screening process. CONCLUSIONS: The methodological quality of SRs was suboptimal and warrants further improvement in order to provide strong evidence of MAD effectiveness and increase applicability of SR results for clinical decision-making.

Skeletal and dental effects of surgically assisted rapid palatal expansion: a systematic review of randomized controlled trials.

BACKGROUND: Surgically assisted rapid maxillary expansion (SARME) is a surgical technique developed to correct transverse discrepancies in skeletally mature patients. However, there is limited evidence concerning the immediate skeletal and dental changes obtained only due to SARME. OBJECTIVE: The aim of the present systematic review is to investigate the immediate skeletal and dental effects of SARME in adult patients with transverse maxillary hypoplasia. SEARCH METHODS: An electronic search of the literature in MEDLINE, The Cochrane Library, Lilacs and Scopus databases was performed. SELECTION CRITERIA: Only randomized controlled trials (RCTs) studies investigating the skeletal and dental effects of SARME procedures in adult patients were included. DATA COLLECTION AND ANALYSIS: The included studies received a methodological quality scoring according to the revised Cochrane risk-of-bias tool for randomized trials. The quality of evidence was assessed by means of the Grading Recommendation Assessment, Development and Evaluation (GRADE) system. For each included study and for each analysed parameter, the difference in means and 95 per cent confidence interval was calculated between baseline and immediate post-expansion. A meta-analysis of original outcome data, if possible, was conducted. RESULTS: Nine articles were selected. The methodological quality ratings indicated that one study was at low risk of bias, seven presented some concerns and only one was at high risk of bias. In all the included studies, the SARME procedure resulted in a significant expansion of the maxillary transverse dimension. The meta-analysis compared skeletal and dental inter-molar width before and after treatment: the mean difference was of 3.3 mm (2.8-3.9) and 7.0 mm (6.1-7.8), respectively (P-value less than 0.001). The quality of evidence was low-moderate. CONCLUSIONS: SARME is effective in obtaining a significant expansion of the maxillary transverse dimension. However, the immediate SARME effect is mainly a molar expansion rather than a pure bone transverse widening of the maxilla. REGISTRATION: The review protocol was registered at PROSPERO database with the registration number CRD42018117967.

Relationship between cephalometric parameters and the apnoea-hypopnoea index in OSA patients: a retrospective cohort study.

OBJECTIVE: The purpose of this study was to assess the relationship between cephalometric parameters and apnoea-hypopnoea index (AHI) controlling for the effect of gender, age, and body mass index (BMI) on a large sample of patients with obstructive sleep apnoea (OSA). METHODS: This retrospective cohort study was conducted on the lateral cephalograms of 253 Caucasian adult OSA patients. Cephalometric analyses were performed using 14 parameters for skeletal and soft tissue morphology, including antero-posterior and vertical jaw relationships, hyoid bone position, soft palate length and thickness, airway space, and tongue length and height. A hierarchical regression was run to examine the amount of variability in AHI that cephalometric variables explained after controlling for patients' general characteristics (gender, age, and BMI). RESULTS: After controlling for gender, age, and BMI, the increase in AHI variance accounted for by cephalometric parameters was equal to 0.103. Among the cephalometric variables, only MP-H and PNS-P were statistically significant (P < 0.05). LIMITATIONS: Given the retrospective nature of the study, it is difficult to assess whether other confounding variables not considered in the present study could have influenced the relationship between cephalometric parameters and AHI. CONCLUSIONS: This study revealed the existence of a relationship between OSA severity and some cephalometric parameters. Indeed soft palate length and vertical position of the hyoid bone were significant predictors of AHI in adult Caucasian OSA patients.

Effect of verbal and written information on pain perception in patients undergoing fixed orthodontic treatment: a randomized controlled trial.

BACKGROUND: Pain can discourage patients from seeking orthodontic treatment or compromise their compliance during therapy. OBJECTIVES: To determine the effects of verbal and written information on orthodontic pain after fixed appliance placement. TRIAL DESIGN: Two-arm parallel design randomized controlled trial. METHODS: Healthy adolescents with permanent dentition enrolled for orthodontic treatment were assigned to the study or control group using computer-generated random lists and allocation concealment with sealed envelopes. Participants completed baseline questionnaires to assess anxiety (State-Trait Anxiety Inventory Trait Version, Form X-2) and somatosensory amplification (Somatosensory Amplification Scale). Brackets were placed in the maxillary arch, from first molar to first molar, and an Australian archwire 0.012 inch was used for alignment. General verbal information on orthodontic treatment was given to all patients by the same clinician. Participants included in the study group received also detailed verbal instructions on orthodontic pain together with a take-home information leaflet by another clinician. Outcome included assessments of pain intensity with a Numerical Rating Scale (NRS) on the day of appliance placement (Day 1, bedtime) and twice a day for the following 6 days (Day 2 to Day 7, morning, bedtime), and analgesic consumption. Participants, statistician, and clinicians who gave general verbal information on orthodontic treatment and instructions about how to score pain intensity were blinded to group assignment. RESULTS: Sixty patients were assigned to the study (n = 30, mean age: 15.4 ± 1.3 years) or control group (n = 30, mean age: 14.7 ± 3.2 years). At baseline, no significant between-group differences were present in terms of anxiety and somatosensory amplification. Orthodontic pain scores were significantly lower in the study group compared with the control one, at bedtime on Day 1 (P < 0.05) and in the morning of Day 2 (P < 0.01). No significant between-group differences were found in following measurements. Overall, analgesic consumption was significantly lower in study compared with the control (P < 0.01). CONCLUSION: A combination of verbal and written information on orthodontic pain after placement of fixed appliances reduced patient's self-reported pain in the early stages. REGISTRATION: This study was not registered.

Dental and skeletal long-term side effects of mandibular advancement devices in obstructive sleep apnea patients: a systematic review with meta-regression analysis.

Background: Mandibular advancement devices (MAD) are effective in reducing apnea episodes and they are frequently used as first-line therapy in obstructive sleep apnea (OSA) patients. Objectives: The MAD must be used every night for a lifetime and since it performs its function discharging the forces on dental elements the aim of this systematic review was to identify the dental and skeletal long-term side effects of MAD therapy and to evaluate the influence of time on them in OSA or snoring patients. Search Methods: An electronic search was performed in MEDLINE, Cochrane Database, Google Scholar Beta, Scopus, and LILACS. Studies until 4 April 2018 were analysed, without language restrictions. Selection Criteria: Randomized controlled trials and cohort studies investigating dental and/or skeletal side effects on adult patients wearing MAD for OSA or snoring treatment with at least 2 years follow-up were included and independently evaluated by two investigators. Data Collection and Analysis: The quality of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) and the risk of bias by means of Cochrane's tools. For each study included and for each dental and/or skeletal parameter, the difference in means and 95% CI was calculated between baseline and follow-up. Results: Twenty-one studies with follow-up between 2 and 11 years were included. The side effects reported were a reduction in overjet, overbite, and in the upper incisor inclination, and an increase in lower incisor inclination, A point-Nasion-B point, and anterior facial height. The meta-regression analysis showed that the side effects were influenced by the therapy duration for all parameters (P < 0.05). The quality of evidence was low/moderate. Conclusions: MAD therapy produces time-related dental and skeletal side effects. After a long period of treatment, the dental side effects are clinically relevant and therefore the clinician should inform the patients about this issue. Since the side effects are progressive, patients need to be continuously monitored over time. Registration: The study protocol was not registered.

Dentoskeletal effects of oral appliance wear in obstructive sleep apnoea and snoring patients.

OBJECTIVES: To evaluate the dentoskeletal changes associated with long-term and continuous mandibular advancement device (MAD) use in sleep-related breathing disorder patients. METHODS: Cephalometric measurements and three-dimensional model analysis were performed at baseline and after 3.5 ± 1.1 years in 20 snoring and obstructive sleep apnoea patients treated with the Silensor® appliance. Intra-group differences were compared using paired t-test or Wilcoxon signed-rank test. A regression analysis was performed for variables that showed a statistically significant difference between time points to evaluate the influence of treatment time and patient's initial characteristics on their variations. The statistical significance was set at P < 0.05. RESULTS: At cephalometric assessment, the maxilla revealed a significant decrease in horizontal position (SNA: -0.4 ± 0.72 degree, P = 0.021) and a significant retroclination of the upper incisor (-1.59 ± 1.07 degree, P < 0.001), while the mandible displayed a significant downward rotation (0.88 ± 1.28 degree, P = 0.006) and a proclination of the lower incisor (2.27 ± 1.38 degree, P < 0.001). Model analysis showed a decrease in upper total space discrepancy (-0.66 ± 0.72 mm, P < 0.002), overjet (OJ; -0.34 ± 0.47 mm, P < 0.011), and overbite (-0.4 ± 0.52 mm, P < 0.004). In the regression analysis, treatment time influenced the lower incisor inclination (Beta = -0.713, P = 0.018) and OJ (Beta = -0.218, P = 0.018); patients' initial characteristics had an effect on OJ (Beta = -0.195, P = 0.011). LIMITATIONS: A larger sample size could increase the generalizability of the findings. CONCLUSION: MAD wear after a mean of 3.5 years determines statistically significant but clinically irrelevant dentoskeletal changes. Their potential occurrence should be thoroughly discussed with patients; regular follow-up visits by a specialist experienced in dental sleep medicine are also mandatory during treatment in addition to polysomnographic examinations.

The effectiveness of different mandibular advancement amounts in OSA patients: a systematic review and meta-regression analysis.

PURPOSE: The therapy with mandibular advancement devices (MADs) represents a treatment option for patients with obstructive sleep apnea (OSA). The literature does not provide evidence regarding the most effective mandibular advancement; therefore, the aim of this systematic review with meta-regression was to investigate the effectiveness of different mandibular advancement amounts in reducing apnea-hypopnea index (AHI) in OSA patients. METHODS: An electronic search was performed in MEDLINE, Cochrane Database, Google Scholar Beta, ISI Web of Knowledge, Scopus, and LILACS to select randomized controlled trials (RCTs) investigating the efficacy of MADs in reducing AHI in adult OSA patients. Inclusion criteria were the diagnosis of OSA and success evaluation performed with a polysomnography, follow-up of maximum 12 months, and protrusion amount reported as a percentage of the maximum mandibular advancement. The quality of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. The success rate of each study was computed: [(mean AHI at baseline-mean AHI after treatment)/mean AHI at baseline]. RESULTS: Thirteen RCTs performing advancements from 50 to 89 % of maximum mandibular protrusion were included. The meta-regression analysis showed that advancement amounts higher than 50 % do not significantly influence the success rate (Q = 0.373, p = 0.541). According to the GRADE score system, the quality of evidence resulted to be moderate. CONCLUSION: The AHI improvement resulted to be not proportional to the mandibular advancement increase. It is plausible that the success of the therapy is influenced by a combination of variables that need closer study.

Periodontal status after surgical-orthodontic treatment of labially impacted canines with different surgical techniques: A systematic review.

INTRODUCTION: Good periodontal status is essential for a successful treatment outcome of impacted maxillary canines. Whereas the surgical technique used for tooth uncovering has been shown not to affect the final periodontal status of palatally impacted canines, its effect on labially impacted canines is still unclear. METHODS: Searches of electronic databases through January 2015 and reference lists of relevant publications were used to identify studies evaluating the periodontal status of labially impacted canines after combined surgical-orthodontic treatment. Two reviewers independently screened the articles, extracted data, and ascertained the quality of the studies. RESULTS: Ninety-one studies were identified; 3 were included in the review. No included study examined the periodontal outcome of the closed eruption technique. Excisional uncovering was reported to have a detrimental effect on the periodontium (bleeding of the gingival margin, 29% vs 7% in the control group; gingival recession, -0.5 mm [SD, 1.0] vs -1.5 mm [SD, 0.8] in the control group; and width of keratinized gingiva, 2.6 mm [SD, 1.4] vs 4.1 mm [SD, 1.5] in the control group). Impacted canines uncovered with an apically positioned flap had periodontal outcomes comparable with those of untreated teeth. CONCLUSIONS: The current literature is insufficient to determine which surgical procedure is better for periodontal health for uncovering labially impacted canines.

Maxillary first premolar inclination in 8- to 11-year-old children: An observational cross-sectional study on panoramic radiographs.

INTRODUCTION: In this study, we examined first premolar inclination in a large sample. METHODS: First premolar inclination, canine inclination, and mesiodistal location were measured on 797 panoramic radiographs of orthodontically untreated children (ages, 8-11 years; 381 boys, 416 girls). The sample comprised 1496 premolars and 1496 canines. A linear mixed-effects model was used to determine the contribution of age, sex, canine inclination, canine sector location, second molar maturational stage (D-G), and dental arch side on premolar inclination. RESULTS: First premolar inclination values (medians and interquartile ranges) were 12.76° (8.12°-19.05°) at 8 years, 11.82° (7.87°-16.04°) at 9 years, 10.40° (6.38°-15.46°) at 10 years, and 9.03° (5.42°-12.81°) at 11 years; 13.86° (8.60°-18.78°) at stage D, 10.56° (7.39°-14.77°) at stage E, 10.43° (6.08°-15.09°) at stage F, and 8.00° (4.62°-10.74°) at stage G. The following equation was selected (Akaike information criteria = 424.99): first premolar inclination (°) = -2.211 + 2.240 (8 years) + 1.363 (9 years) + 0.955 (10 years) + 0.387 (canine inclination) + 0.902 (right side) + 2.320 (stage D) + 6.320 (sector 1) + 5.446 (sector 2) + 3.803 (sector 3). There was no difference between percentiles constructed by age and maturational stage. CONCLUSIONS: First premolar inclination decreases during the mixed dentition and is moderately correlated with canine inclination.

The effect of diode superpulsed low-level laser therapy on experimental orthodontic pain caused by elastomeric separators: a randomized controlled clinical trial.

The aim of this study was to evaluate the efficacy of diode superpulsed low-level laser therapy (SLLLT) in reducing experimentally induced orthodontic pain. Overall, 120 subjects (23.01 ± 1.39 years) were enrolled for a clinical trial. Subjects were randomly assigned to upper (U, N = 60) or lower (L, N = 60) jaw groups. All subjects received 4 elastomeric separators mesial and distal to the upper (U group) or lower (L group) right first molar and bicuspids. Each subject of the U and L groups was randomly assigned to laser (Ul, N = 20 and Ll, N = 20), placebo (Up, N = 20 and Lp, N = 20) or control (Uc, N = 20 and Lc, N = 20) sub-groups. Subjects in laser groups received a single GaAs diode SLLLT application (910 nm, 160 mW, beam diameter of 8 mm, applied for 340 s) immediately after placing orthodontic separators. Placebo groups received a simulated SLLLT and controls did not receive any therapy. All participants compiled a survey on pain duration and a 100-mm visual analogue scale immediately after the separators placement and after 12, 24, 36, 48, 72, and 96 h. Pain intensity of laser groups was significantly lower compared to placebo and control groups (p = 0.0001). In the laser group, 70% of subjects felt pain, while in the placebo and control groups all subjects felt pain (p = 0.0001). The end of pain occurred earlier in laser compared to placebo and control groups (p = 0.021). A single-diode SLLLT application appeared to be effective in reducing the intensity and duration of experimentally induced orthodontic pain and could be used in daily orthodontic practice.