Craniofacial features of adult obese obstructive sleep apnoea patients in relation to the obesity onset - A pilot study.

INTRODUCTION: Obesity and craniofacial structures are aetiologies of obstructive sleep apnoea (OSA). The effect of obesity onset on the craniofacial development and growth of obese OSA subjects has been suggested, but supporting data were lacking. This study aimed to assess the craniofacial features of adult obese OSA patients in relation to their obesity onset. MATERIALS AND METHODS: A total of 62 adult OSA patients were included in the study, consisting of 12 early-onset (i.e. before puberty), 21 late-onset (i.e. after puberty) and 29 non-obese. All participants underwent a sleep study and cephalometric radiograph. Cephalometric analysis was conducted to measure the craniofacial features among the groups. RESULTS: The early obesity onset group (n = 12) showed a more prognathic mandible, longer lower facial height, protrusive incisors, a more caudal position of the hyoid bone and a wider lower airway. The late-onset group (n = 21) had more proclined and protrusive upper incisors, a shallower overbite, a more inferiorly positioned hyoid bone and an obtuse craniocervical angle. The overall obese group showed a combination of the findings above, plus a shorter soft palate and shorter airway length. There was no significant difference between early and late obesity onset groups. However, the early group showed a tendency for a shallower or decreased mandibular plane angle and deeper overbite. CONCLUSIONS: The current pilot study had many limitations but holds important information as a hypothesis generator. Craniofacial features of OSA patients with different obesity onset showed discrepancies and were distinguished from non-obese controls. Adult OSA patients with an early obesity onset showed a tendency for a more hypodivergent growth pattern than those with a late obesity onset.

Validation of three-dimensional facial imaging captured with smartphone-based photogrammetry application in comparison to stereophotogrammetry system.

Statement of problem: The development of facial scanners has improved capabilities to create three-dimensional (3D) virtual patients for accurate facial and smile analysis. However, most of these scanners are expensive, stationary and involve a significant clinical footprint. The use of the Apple iPhone and its integrated "TrueDepth" near-infrared (NIR) scanner combined with an image processing application (app) offers the potential to capture and analyze the unique 3D nature of the face; the accuracy and reliability of which are yet to be established for use in clinical dentistry. Purpose: This study was designed to validate both the trueness and precision of the iPhone 11 Pro smartphone TrueDepth NIR scanner in conjunction with the Bellus3D Face app in capturing 3D facial images in a sample of adult participants in comparison to the conventional 3dMDface stereophotogrammetry system. Material and methods: Twenty-nine adult participants were prospectively recruited. Eighteen soft tissue landmarks were marked on each participant's face before imaging. 3D facial images were captured using a 3dMDface system and the Apple iPhone TrueDepth NIR scanner combined with the Bellus3D Face app respectively. The best fit of each experimental model to the 3dMD scan was analyzed using Geomagic Control X software. The root mean square (RMS) was used to measure the "trueness" as the absolute deviation of each TrueDepth scan from the reference 3dMD image. Individual facial landmark deviations were also assessed to evaluate the reliability in different craniofacial regions. The "precision" of the smartphone was tested by taking 10 consecutive scans of the same subject and comparing those to the reference scan. Intra-observer and inter-observer reliabilities were assessed using the intra-class correlation coefficient (ICC). Results: Relative to the 3dMDface system, the mean RMS difference of the iPhone/Bellus3D app was 0.86 ± 0.31 mm. 97% of all the landmarks were within 2 mm of error compared with the reference data. The ICC for intra-observer reproducibility or precision of the iPhone/Bellus3D app was 0.96, which was classified as excellent. The ICC for inter-observer reliability was 0.84, which was classified as good. Conclusions: These results suggest that 3D facial images acquired with this system, the iPhone TrueDepth NIR camera in conjunction with the Bellus3D Face app, are clinically accurate and reliable. Judicious use is advised in clinical situations that require high degrees of detail due to a lack of image resolution and a longer acquisition time. Generally, this system possesses the potential to serve as a practical alternative to conventional stereophotogrammetry systems for use in a clinical setting due to its accessibility and relative ease of use and further research is planned to appraise its updated clinical use.

Dental sleep-related conditions and the role of oral healthcare providers: A scoping review.

Dental sleep medicine as a discipline was first described about a quarter of a century ago. Snoring, obstructive sleep apnea, sleep bruxism, xerostomia, hypersalivation, gastroesophageal reflux disease, and orofacial pain were identified as dental sleep-related conditions. This scoping review aimed to: i) identify previously unidentified dental sleep-related conditions; and ii) identify the role of oral healthcare providers in the prevention, assessment, and management of dental sleep-related conditions in adults. A systematic literature search was conducted in PubMed, Embase.com, Web of Science, and Cochrane. Studies that reported an actual or likely role of oral healthcare providers in the prevention, assessment, and/or management of sleep-related conditions were included. Of the 273 included studies, 260 were on previously listed dental sleep-related conditions; the other 13 were on burning mouth syndrome. Burning mouth syndrome was therefore added to the list of dental sleep-related conditions for the first aim and categorized into sleep-related orofacial pain. For the second aim, the role of oral healthcare providers was found to be significant in the prevention, assessment, and management of obstructive sleep apnea and sleep bruxism; in the assessment and management of snoring, sleep-related orofacial pain, and oral dryness; and in the assessment of sleep-related gastroesophageal reflux condition.

Craniofacial form differences between obese and nonobese children.

INTRODUCTION: Current evidence suggests that obesity is correlated with differences in craniofacial form in children and adolescents. Here, we sought to test this hypothesis by evaluating the craniofacial form of obese and nonobese preorthodontic patients, using 2D cephalometric data combined with cephalometric and geometric morphometric approaches. METHODS: Height, weight, age, and lateral cephalometric radiographs were gathered from patients aged 7-16 years before beginning orthodontic treatment at the University of British Columbia. Based on their body mass index, 24 obese patients were age, sex, and Angle classification of malocclusion matched with nonobese controls. Cephalometric radiographs were annotated, and coordinates of landmarks were used to obtain linear and angular cephalometric measurements. Geometric morphometric analyses were performed to determine overall craniofacial form differences between cohorts. Dental maturation index scores and cervical vertebral maturation scores were recorded as an indicator of skeletal maturation. RESULTS: Cephalometric analysis revealed that the maxillary length and gonial angle are the only marginally larger metrics in obese subjects than in control subjects. However, principal component and discriminant analyses (geometric morphometrics) confirmed that the overall craniofacial form of obese patients differs statistically from that of control patients. Obese patients tend to be slightly mandibular prognathic and brachycephalic. Dental maturation index scores were statistically higher in the obese group than in the control group, with no statistical difference in cervical vertebral maturation scores. CONCLUSIONS: Our data reveals a subtle but significant difference in cranial skeletal morphology between obese and nonobese children and adolescents, suggesting a correlation between craniofacial form and physiological/metabolic phenotypes of subjects. It is likely that with continued growth, these differences may increase. Recording body mass index as part of the orthodontic records for patients may help in supporting the assessment of craniofacial form.

Use of facial stereophotogrammetry as a screening tool for pediatric obstructive sleep apnea by dental specialists.

STUDY OBJECTIVES: To evaluate facial 3-dimensional (3D) stereophotogrammetry's effectiveness as a screening tool for pediatric obstructive sleep apnea (OSA) when used by dental specialists. METHODS: One hundred forty-four participants aged 2-17 years, including children fully diagnosed with pediatric OSA through nocturnal polysomnography or at high-risk or low-risk of pediatric OSA, participated in this study. 3D stereophotogrammetry, Craniofacial Index, and Pediatric Sleep Questionnaire were obtained from all participants. Ten dental specialists with interest in pediatric sleep breathing disorders classified OSA severity twice, once based only on 3D stereophotogrammetry and then based on 3D stereophotogrammetry, Craniofacial Index, and Pediatric Sleep Questionnaire. Intrarater and interrater reliability and diagnostic accuracy of pediatric OSA classification were calculated. A cluster analysis was performed to identify potential homogeneous pediatric OSA groups based on their craniofacial features classified through the Craniofacial Index . RESULTS: Intrarater and interrater agreement suggested a poor reproducibility when only 3D facial stereophotogrammetry was used and when all tools were assessed simultaneously. Sensitivity and specificity varied among clinicians, indicating a low screening ability for both 3D facial stereophotogrammetry, ranging from 0.36-0.90 and 0.10-0.70 and all tools ranging from 0.53-1.0 and 0.01-0.49, respectively. A high arched palate and reversed or increased overjet contributed to explaining how participating dental clinicians classified pediatric OSA. CONCLUSIONS: 3D stereophotogrammetry-based facial analysis does not seem predictive for pediatric OSA screening, alone or combined with the Pediatric Sleep Questionnaire and Craniofacial Index when used by dental specialists interested in sleep-disordered breathing. Some craniofacial traits, more specifically significant sagittal overjet discrepancies and an arched palate, seem to influence participating dental specialists' classification. CITATION: Fernandes Fagundes NC, Carlyle T, Dalci O, et al. Use of facial stereophotogrammetry as a screening tool for pediatric obstructive sleep apnea by dental specialists. J Clin Sleep Med. 2022;18(1):57-66.

Long-term periodontal changes associated with oral appliance treatment of obstructive sleep apnea.

STUDY OBJECTIVES: To characterize the mandibular anterior teeth crown height as a marker of periodontal changes and bone loss as a side effect of an oral appliance worn for a minimum of 4.5 years. METHODS: This retrospective study conducted in patients with healthy baseline periodontium recruited participants among consecutive sleep apnea patients treated with an oral appliance between 2004 to 2014. Eligible participants were recalled for a follow-up visit at which a periodontal examination was performed and a lateral cephalogram and dental impressions were obtained. Clinical crown height for mandibular anterior teeth and cephalometric variables were measured and compared before and after treatment. A full periodontal evaluation was performed at the follow-up visit. RESULTS: Twenty-one patients enrolled with a mean treatment length of 7.9 ± 3.3 years. For the mandibular anterior teeth, clinical crown height did not change over the evaluated period. At follow-up, all the periodontal assessed variables were within normal limits, with the mean probing depth of 1.4 ± 0.5 mm, recession 0.6 ± 1.1 mm, and clinical attachment loss 0.8 ± 1.0 mm. Compared with baseline, there was a significant proclination of mandibular incisors (mean increase of 5.1 degrees) with the continued use of an oral appliance. Gingival levels were maintained with clinically insignificant changes during the observation period. CONCLUSIONS: Inclination of the mandibular incisors increases significantly with the use of an oral appliance in patients with obstructive sleep apnea. Positional changes in these teeth were not associated with any measured evidence of increase in clinical crown height or gingival recession. CITATION: Heda P, Alalola B, Almeida FR, Kim H, Peres BU, Pliska BT. Long-term periodontal changes associated with oral appliance treatment of obstructive sleep apnea. J Clin Sleep Med. 2021;17(10):2067-2074.

Outcomes of orthodontic treatment performed by individual orthodontists vs 2 orthodontists collaborating on treatment.

INTRODUCTION: One factor that can affect treatment outcomes is the treatment provider, and this factor has not been extensively studied. This research aimed to evaluate orthodontic treatment quality, length, and efficiency when 2 orthodontists collaborated on treatment, compared with the treatment provided solely by either orthodontist. METHODS: A total of 150 consecutively treated subjects were divided into 3 equal groups based on the treating clinician. Patients in group A were treated by orthodontist A, group B by orthodontist B, and group C by both orthodontists in collaboration. The Peer Assessment Rating (PAR), Index of Complexity, Outcome, and Need (ICON), American Board of Orthodontics-Discrepancy Index, and American Board of Orthodontics-Cast and Radiographic Evaluation were used to assess the pretreatment and posttreatment status. Patient age, gender, type of malocclusion, extraction treatment, orthognathic surgery, treatment length, number of visits, and treatment efficiency index were assessed. RESULTS: Posttreatment PAR and ICON indices showed excellent results in all 3 groups. American Board of Orthodontics-Cast and Radiographic Evaluation was significantly higher in group C (25.3 points) than in group A (21.5 points) or group B (22.0 points) (P = 0.014). Patients in group A had significantly shorter treatment time (23 months) than those in either group B or C (26 months) (P = 0.011). Patients in group C required more appointments (27 visits) than those in either group A or B (23 and 25 visits, respectively). The treatment efficiency index showed no statistically significant difference among the 3 groups. CONCLUSIONS: There was no difference in treatment quality among the 3 groups, as assessed by the PAR index and ICON. Jointly treated cases required 2 to 4 more visits and had higher American Board of Orthodontics-Cast and Radiograph Evaluation scores than those treated by either orthodontist. Complex cases required 6 to 7 more months when they were treated collaboratively.

Obstructive sleep apnea and orthodontics: An American Association of Orthodontists White Paper.

The Board of Trustees of the American Association of Orthodontists asked a panel of medical and dental experts in sleep medicine and dental sleep medicine to create a document designed to offer guidance to practicing orthodontists on the suggested role of the specialty of orthodontics in the management of obstructive sleep apnea. This White Paper presents a summary of the Task Force's findings and recommendations.

Long-term side effects of sleep apnea treatment with oral appliances: nature, magnitude and predictors of long-term changes.

OBJECTIVES: Oral appliances for the treatment of obstructive sleep apnea (OSA) reduce upper airway collapse by advancing the mandible (OAm) and associated soft tissues. OAm are well tolerated but have side effects, mainly dental movement. It is not yet clear whether there are irreversible skeletal changes associated with treatment. As oral appliance treatment for OSA is a life-long therapy, careful and extended follow-up of patients is required. The objectives of this study were to evaluate the magnitude and progression of the dental and skeletal changes associated with long-term treatment, in addition to determining the predictors of the changes. METHODS: Lateral cephalograms of adults treated for primary snoring or mild to severe OSA with a custom-made titratable OAm for a minimum of eight years were retrospectively studied. The magnitude and rate of progression of any changes over time was determined and initial patient and dental characteristics were investigated as possible predictors of the observed side effects. RESULTS: Records of 62 patients with an average treatment time of 12.6 years (range:8-21 years) were included. Cephalometric analysis revealed significant (p < 0.001) maxillary incisor retroclination (mean of ≈6°) and mandibular incisor proclination (mean of ≈8°) over the observation period. Maxillary incisors demonstrated a constant rate of retroclination -0.5°/year, the rate of mandibular incisors proclination was variable. The number of treatment years was significantly associated with these variables (p < 0.001). A greater body mass index (BMI) and Subspinale, Nasion, Supramentale angle (ANB) were associated with more maxillary and mandibular incisor proclination respectively. Although statistically significant (p < 0.001) skeletal changes were noted over this extended observation period, the difference in the Sella, Nasion, Supramentale point B (SNB) and mandibular plane angles were approximately 1° and were deemed not clinically significant. CONCLUSIONS: This study represents the longest observation period to date examining OAm side effects with up to 21 years of follow up for some patients. It confirms that there are significant and progressive dental changes with prolonged OAm use. Conversely, over the same time period skeletal or postural changes were negligible. Additionally, treatment duration was the predictor consistently associated with the magnitude of the observed side effects.

Reliability of upper airway assessment using CBCT.

Background: Upper airway analysis is an often-cited use of CBCT imaging by orthodontists; however, the reliability of airway measurements using this technology is not fully established. Objective: To determine the intra-examiner and inter-examiner reliability of the complete process of volumetric and cross-sectional area assessments of the upper airway using CBCT imaging. Materials and Methods: Six examiners of varying levels of education and clinical experience performed the steps necessary for airway analysis, including manual orientation, slice and threshold selection and measured nasopharyngeal, oropharyngeal, hypopharyngeal and total upper pharyngeal airway volumes in addition to minimum cross-sectional area on the CBCT images of 10 patients. All measurements were repeated after 4-weeks. Intra- and inter-examiner reliability was calculated using ICC and 95% CI. Results: Threshold selection showed poor intra- and poor inter-examiner reliability, whereas minimum cross-sectional area showed moderate intra- and poor inter-examiner reliability. Intra-examiner reliability of volumetric measurements varied based on the region assessed with ICC ranging from 0.747 to 0.976, and was worst for hypopharynx and best for the oropharynx. Inter-examiner reliability of volume measurements was generally lower, with ICC ranging from 0.175 to 0.945, and was worst for nasopharynx and best for the oropharynx. Conclusions: This study, for the first time, assessed the reliability of upper airway analysis with CBCT when all steps of image processing and measurement are performed by each examiner. Reliability improved with examiner experience, though was generally low for the hypopharynx and nasopharynx volumes and overall minimal cross-sectional area. The oropharyngeal volume was the only parameter to have excellent intra- and inter-examiner reliability.

Tooth Movement Associated With CPAP Therapy.

ABSTRACT: We report on a rarely documented side effect-tooth movement-associated with positive airway pressure therapy. A 64-year-old woman presented to an orthodontic practice for evaluation of unexplained tooth movement and spaces opening between her anterior teeth. The patient recently received a diagnosis of mild obstructive sleep apnea, for which she had been using continuous positive airway pressure (CPAP) delivered by a nasal pillows interface for the past 18 months. Follow-up questioning revealed that shifting of the teeth was first noticed in the months following the initiation of CPAP and the result of forward thrusting of the tongue during use. Following 12 months of orthodontic treatment, the malocclusion was corrected and teeth returned to their pretreatment positions. Unwanted tooth movement, although a minor sequela, can have a meaningful effect on quality of life. With improved awareness of this issue, the patient experience and ultimately adherence with CPAP treatment can be improved.

Adherence to Treatment with Removable Oral Appliances: the Past and the Future.

Oral appliances (OAs) are frequently used in orthodontics and for the treatment of obstructive sleep apnea. Because OAs can be inserted and removed by patients themselves, the patient's cooperation is a major component of effective treatment. In this review, we provide an overview of factors studied in the past that affect adherence to OA use in orthodontics and dental sleep medicine. We also describe future directions in adherence and the use of objective microsensor technology to measure adherence in these patients. Because removable oral appliances (OAs) can be inserted and removed by patients themselves, their cooperation and adherence to therapy are necessary to achieve success.1,2 Removable OAs, such as headgear, removable retainers and functional appliances, are used in orthodontics to correct malocclusions. In the field of sleep medicine, removable OAs are increasingly used as an option in the treatment of patients with obstructive sleep apnea (OSA).

Accuracy of Thermosensitive Microsensors Intended to Monitor Patient Use of Removable Oral Appliances.

OBJECTIVE: The aim of this study was to evaluate the accuracy of 3 thermosensitive microsensors that record "wear time" of removable oral appliances (OAs). METHODS: For in vitro testing, TheraMon (sensor T, n = 20), AIR-AID SLEEP (sensor A, n = 30) and DentiTrac (sensor D, n = 16) microsensors were placed in a water bath to simulate long and short durations of wear. Their accuracy was also assessed when they were embedded in 3 materials: acrylic, polyvinylchloride and thermoactive acrylic. In vivo testing included 14 volunteers, who wore maxillary retainers embedded with sensors A and D for 30 nights. Logs of appliance use were compared with readouts from the sensors. RESULTS: In the in vitro long duration of wear assessment, sensor A, with a mean absolute response difference (MARD) of 1.67 min. (SD 1.41), was significantly more accurate than sensor T (MARD 3.53 min., SD 9.80) and sensor D (MARD 4.48 min., SD 8.46). For short duration of wear, sensor A (MARD 1.41 min., SD 3.60) and sensor T (MARD 1.68 min., SD 7.64) were equal in accuracy and significantly better than sensor D (MARD 14.07 min., SD 10.20). The embedding material had no effect on the recording accuracies of the microsensors. In vivo, there was no significant difference between sensors A and D. CONCLUSION: All 3 microsensors are highly accurate and reliable and can be used to record wear time of a removable OAs fabricated from various materials.

Reliability of upper pharyngeal airway assessment using dental CBCT: a systematic review.

BACKGROUND: Upper airway analysis is an often-cited use of cone beam computed tomography (CBCT) imaging in orthodontics. However, the reliability of this process in a clinical setting is largely unknown. OBJECTIVE: Our objective was to systematically review the literature to evaluate the reliability of upper pharyngeal airway assessment using dental CBCT. SEARCH METHODS: MEDLINE, EMBASE, Web of Science, and Google Scholar were searched through June 2015. SELECTION CRITERIA: Human studies that measured reliability of upper airway assessment in patients using CBCT as part of the study protocol were considered. DATA COLLECTION AND ANALYSIS: The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) was followed. Data were collected on overall study characteristics and measurements, CBCT unit and machine settings used, and examination characteristics of the included studies. Methodological quality of the included studies was evaluated. RESULTS: Forty-two studies were evaluated, representing the CBCT scans of 956 patients. Studies included a wide variety of patients and CBCT machines with various scan settings. Only five studies were deemed high quality. The available evidence indicates that under specific restricted conditions there is moderate to excellent intra- and inter-examiner reliability. Airway volume demonstrated greater intra- and inter-examiner reliability than did minimum cross-sectional area. However, significant methodological limitations of the current literature, most importantly a lack of manual orientation of the images and selection of threshold sensitivity in study protocols, suggest that reliability has not been adequately established. CONCLUSIONS: The current literature reports moderate to excellent reliability, with airway volume having higher reliability than minimum cross-sectional area. However, only limited aspects of the process of airway analysis have been evaluated, indicating that further research is required to adequately establish the reliability of upper pharyngeal airway assessment of patients using dental CBCT. REGISTRATION: None.

Effect of orthodontic treatment on the upper airway volume in adults.

INTRODUCTION: The aim of this study was to examine the effects of orthodontic treatment with and without extractions on the anatomic characteristics of the upper airway in adults. METHODS: For this retrospective study, the pretreatment and posttreatment cone-beam computed tomography scans of 74 adult patients meeting defined eligibility criteria were analyzed. Imaging software was used to segment and measure upper airway regions including the nasopharynx, the retropalatal, and retroglossal areas of the oropharynx, as well as the total airway. The Wilcoxon signed rank test was used to compare volumetric and minimal cross-sectional area changes from pretreatment to posttreatment. RESULTS: The reliability values were high for all measurements, with intraclass correlation coefficients of 0.82 or greater. The volumetric treatment changes for the extraction and nonextraction groups were as follows: total airway, 1039.6 ± 3674.3 mm3 vs 1719.2 ± 4979.2 mm3; nasopharynx, 136.1 ± 1379.3 mm3 vs -36.5 ± 1139.8 mm3; retropalatal, 412.7 ± 3042.5 mm3 vs 399.3 ± 3294.6 mm3; and retroglossal, 412.5 ± 1503.2 mm3 vs 1109.3 ± 2328.6 mm3. The treatment changes in volume or minimal cross-sectional area for all airway regions examined were not significantly (P >0.05) different between the extraction and nonextraction groups. CONCLUSIONS: Orthodontic treatment in adults does not cause clinically significant changes to the volume or the minimally constricted area of the upper airway. These results suggest that dental extractions in conjunction with orthodontic treatment have a negligible effect on the upper airway in adults.

Prediction of oral appliance treatment outcomes in obstructive sleep apnea: A systematic review.

While oral appliances (OA) have demonstrated good efficacy in patients ranging from mild to severe levels of obstructive sleep apnea (OSA), this form of treatment is not completely effective in all patients. As a successful treatment response is not dependent solely on apnea hypopnea index severity, the prediction of OA treatment efficacy is of key importance for efficient disease management. This systematic review aims to investigate the accuracy of a variety of clinical and experimental tests for predicting OA treatment outcomes in OSA. A systematic literature review was conducted and the quality of the selected studies was assessed using the quality assessment of diagnostic accuracy studies (QUADAS-2) tool. Some 17 studies involving various prediction methods were included in this review. The predictive accuracy varied depending on the definitions of treatment success used as well as the type of index test. The studies with the best predictive accuracy and lowest risk of bias and concerns of applicability used a multisensor catheter. While a remotely controlled mandibular positioner study showed high accuracy, there was a high risk of bias. The available information on the validity of predictive index tests is very useful in clinical practice and allows for greater disease management efficiency.

Endoscopy evaluation to predict oral appliance outcomes in obstructive sleep apnoea.

The objective of this study was to determine the utility of nasoendoscopy of the upper airway as a predictor of the efficacy of oral appliance treatment in obstructive sleep apnoea (OSA).A total of 61 consecutive patients with moderate-to-severe polysomnographically diagnosed OSA were recruited for this study. Using nasoendoscopy, we prospectively assessed the velopharynx and oro/hypopharynx in each patient while awake and in the supine position. We measured cross-sectional area (CSA), and anteroposterior and lateral diameters of the airway before and after mandibular advancement, and expressed the changes in dimensions as expansion ratios (after/before). We then compared the measurements of responders and nonresponders with oral appliance treatment.The expansion ratio (median (interquartile range)) for the CSA was greater in responders compared with nonresponders in the velopharynx (2.9 (2.3-5.0) versus 1.7 (1.5-1.9), p<0.001) and in the oro/hypopharynx (3.4 (2.5-5.6) versus 2.4 (1.8-3.7), p<0.05). Baseline apnoea-hypopnoea index and the CSA expansion ratio of the velopharynx were independent predictors of oral appliance treatment outcome based on a multivariate logistic regression analysis. The estimated area under the receiver operator characteristic curve was 0.87 and the cut-off value of the expansion ratio was 2.00.These results indicate that nasoendoscopy may have significant clinical utility in predicting the success of oral appliance treatment.

Changes in anteroposterior position and inclination of the maxillary incisors after surgical-orthodontic treatment of skeletal class III malocclusions.

PURPOSE: The purpose of this study was to evaluate and compare the anteroposterior (AP) position and inclination of the maxillary incisors in subjects with class I normal occlusion and a harmonious profile with patients with skeletal class III malocclusions, and to investigate the changes in maxillary incisor inclination and AP position after surgical-orthodontic treatment in class III patients. MATERIAL AND METHODS: Sixty-five subjects (35 female and 30 male; mean age: 21.8 ± 3.89 years) with normal profiles and class I skeletal and dental patterns were selected as a control sample. Sixty-seven patients (38 female and 29 male; mean age: 21.3 ± 3.31 years) with skeletal and dental class III malocclusions who sought surgical-orthodontic treatment were used as the study sample. Subjects were asked to smile and profile photographs were taken with the head in a natural position and the maxillary central incisors and the forehead in full view; cephalograms were taken and superimposed on the profile pictures according to the outline of the forehead and nose. Forehead inclination, maxillary incisor facial inclination and the AP position of the maxillary central incisor relative to the forehead (FAFFA) were measured on the integrated images and statistical analyses were performed. RESULTS: In both groups, there were no significant male/female differences in either the maxillary central incisor inclination or AP position. Female subjects had a significantly steeper forehead inclination compared with males (P < 0.001) in both groups. After combined surgical-orthodontic treatment, the significant labial inclination (P < 0.001) and posterior positioning (P < 0.001) of the maxillary central incisors had been corrected to close to normal range (P > 0.05). In the control group, 84.6% had the facial axial point (FA) of their maxillary central incisors positioned between lines through the forehead facial axis (FFA) point and the glabella. In the study group, however, 79.1% had the maxillary central incisors positioned posterior to the line through the FFA point and the difference with the control group was statistically significant (P < 0.001). The position of the maxillary central incisors was strongly correlated with forehead inclination in the control sample (r(2) = 0.456; P < 0.01), but only a poor correlation was detected in the class III group (r(2) = 0.177; P > 0.05). CONCLUSIONS: With the integrated radiograph-photograph method, the lateral cephalogram was reoriented, which makes it possible to accurately measure the variables on profile photographs. The AP position and inclination of the maxillary central incisors relative to the forehead plays an important role in the esthetics of the profile during smiling and could be an important variable to be considered during diagnosis and treatment planning.

A Pilot Study on the Dentoalveolar and Skeletal Effects of Two Functional Appliances in Class II, Division 1 Growing Children.

UNLABELLED: The aim of this preliminary study was to compare the dentoalveolar and skeletal effects of two different Removable Functional Appliances (RFAs) in growing Class II, Division 1 subjects based on pre- and post-treatment cephalometric analyses. Forty subjects with Class II, Division 1 malocclusions were recruited from the undergraduate orthodontic clinic at the University of British Columbia for this clinical trial. All subjects were selected under the same inclusion and exclusion criteria and full orthodontic records were obtained for each subject. They were divided into two groups: 20 (12 males) in RFA-1 group and 20 (14 males) in RFA-2 group. RESULTS: There were no significant differences between the RFA-1 and RFA-2 groups in insertion age (10.4 ± 1.3 years and 10.7 ± 1.4 years, respectively) or treatment duration (163 ± 6.7 months and 16.1 ± 65 months, respectively). There was no significant difference in cephalometric variables between the two groups at baseline. After treatment, both groups demonstrated a statistically significant (P < 0.05) increased SNB and L1-Apo; decreasedANB, Wits, overjet and overbite. CONCLUSIONS: The functional effects of RFA-1 and RFA-2 are comparable in Class II, Division 1 pre-adolescent patients in the same age group. The RFA-1 is effective in generating treatment changes as the suggested wear time was only during sleep.d.