Three-dimensional analysis of upper airways in Class II malocclusion children with obstructive sleep apnea.

BACKGROUND: Morphometric evaluation of upper airways helps in identifying potential craniofacial anatomy that may predispose to pediatric obstructive sleep apnea (OSA). This study evaluated upper airway parameters three-dimensionally in children with OSA, with Class II malocclusion and a retrognathic mandible, to identify cutoff values for cone-beam computed tomography measurements that may predict the presence and severity of pediatric OSA. METHODS: The study comprised 47 growing children with OSA with Class II malocclusion and 47 low-risk OSA-matched controls. Upper airway was segmented into nasopharynx, oropharynx, and hypopharynx using cone-beam computed tomography and MIMICS16.0 software. Parameters included volume, minimum cross-sectional area (CSAmin), anterioposterior and lateral distances of CSAmin, and upper airway length. RESULTS: The volume, cross-sectional area (CSAmin), and anteroposterior and lateral distances of CSAmin were significantly decreased at the level of the oropharynx in patients with OSA. At the level of the hypopharynx, CSAmin was significantly narrower and upper airway length was significantly increased in patients with OSA. OSA predictive cutoff values were proposed as 41.36 mm2 CSAmin at the level of oropharynx, 52.45 mm2 CSAmin at the level of hypopharynx, and 55.47 mm upper airway length. Only CSAmin at the level of the oropharynx had an independent association with OSA severity (P = 0.021). CONCLUSIONS: Significant differences were found in the upper airway parameters of children with OSA compared with corresponding controls. CSAmin may represent part of the issues that play a role in the pathogenesis of OSA and may serve as a predictive of disease severity.

Tonsil Size and Mallampati Score as Clinical Predictive Factors for Obstructive Sleep Apnea Severity in Children.

AIM AND OBJECTIVE: The aim of this study was to determine the clinical utility of body mass index (BMI), tonsil size, and Mallampati scoring in predicting both the presence of and severity of pediatric obstructive sleep apnea (OSA). MATERIALS AND METHODS: This prospective cross-sectional study comprised 78 growing children in the age range of 11-14 years with polysomnography (PSG)-proven OSA and 86 non-OSA corresponding controls. BMI, tonsil size (Friedman grading scale), and Mallampati score were determined for both groups, and related differences were assessed with a t-test, while their independent association with OSA severity was tested with a regression analysis. Statistical significance was set at p <0.05. RESULTS: Male gender, BMI, tonsil size, and Mallampati score were significantly higher in the OSA group (p < 0.05). A significant correlation was recorded between the Mallampati score and OSA severity (p < 0.01), but not with BMI or tonsil size (p > 0.05). For every 1-point increase in the Mallampati scale, the apnea-hypopnea index (AHI) increased by more than five events per hour in the bivariate analysis and by more than three events per hour in the multivariate analysis. CONCLUSION: Male gender, increased BMI, high tonsil, and Mallampati scores were clinical indicators of the presence of OSA. However, only Mallampati scale had a significant association with OSA severity. Clinical diagnostic indicators should be established and encouraged especially in community-based studies. CLINICAL SIGNIFICANCE: Clinical diagnostic indicators are very useful in examining and screening children who are at risk of developing OSA as PSG is expensive and unsuitable for universal use in the pediatric population.

A comparison of the treatment effects of the Forsus Fatigue Resistance Device and the Twin Block appliance in patients with class II malocclusions.

OBJECTIVES: We evaluated the skeletal and dentoalveolar effects of the Forsus Fatigue Resistance Device (FRD) and the Twin Block appliance (TB) in comparison with nontreated controls in the treatment of patients with class II division 1 malocclusion. MATERIALS AND METHODS: THIS RETROSPECTIVE STUDY INCLUDED THREE GROUPS: TB (n=37; mean age, 11.2 years), FRD (n=30; mean age, 12.9 years), and controls (n=25; mean age, 12.6 years). Lateral cephalograms were evaluated at T1 (pretreatment) and at T2 (postappliance removal/equivalent time frame in controls). Cephalometric changes were evaluated using the Clark analysis, including 27 measurements. RESULTS: Sagittal correction of class II malocclusion appeared to be mainly achieved by dentoalveolar changes in the FRD group. The TB was able to induce both skeletal and dentoalveolar changes. A favorable influence on facial convexity was achieved by both groups. Significant upper incisor retroclination occurred with the TB (-12.42°), whereas only -4° was observed in the FRD group. The lower incisors proclined more in the FRD group than the TB group. Incisor overjet reduction was 62% in the TB group versus 56% in the FRD group. Molar relation was corrected in both functional groups, resulting in a class I relation, although no change appeared in the control sample. CONCLUSION: Both appliances were effective in correcting the class II malocclusion. Both the FRD and the TB induced significant maxillary and mandibular dentoalveolar changes; skeletal changes were induced by TB but not FRD therapy.