The aim of this study was to compare the skeletal and soft tissue patterns between obstructive sleep apnoea (OSA) patients and control group of non-OSA patients. Fifty Malays (32 males and 18 females) aged 18-65 years divided into two equal groups 25 (17 males and 8 females) with OSA and a control group 25 subjects (15 males and 10 females). Both groups were diagnosed using polysomnography. Nineteen variables related to craniofacial skeletal and soft tissue morphology were measured on lateral cephalometric films. Analysis of covariance was used to compare the means between the two groups. The results showed that OSA subjects had a significant increase in body mass index (BMI) and neck circumference than the control group. The soft palate and tongue were longer and thicker in OSA patients. In addition, upper, middle, and lower posterior airway spaces were narrower, the hyoid bone was more inferior and posterior, and the cranial base flexure angle was significantly acute when compared with the control group. The findings indicate that craniofacial abnormalities play significant roles in the pathogenesis of OSA in Malay patients.
The association between dental arch morphology and the aetiology of obstructive sleep apnoea (OSA) is not clear. To compare dental arch morphology in 108 Asian adults with and without ''OSA, overnight'' hospital polysomnography was performed, and sleep reports were obtained for all subjects. Standardized digital photographs were also taken of the subjects' upper and lower study models. Using 25 homologous landmarks, mean OSA and control dental arch configurations were computed, and subjected to finite-element morphometry (FEM), t-tests and principal components analysis (PCA). Mean upper and lower OSA dental arch morphologies were statistically different from respective Control upper and lower arch morphologies (P < 0.05). FEM of the upper arch indicated that the mean OSA configuration was 7-11% narrower in the transverse plane in the incisor and canine regions when compared with the control configuration, and inter-landmark analysis (ILA) confirmed this finding. FEM for the lower arch indicated that the mean OSA configuration was 10-11% narrower in the antero-posterior plane in the pre-molar and molar regions, and confirmed by ILA. Using PCA, significant differences were also found between the two groups in the lower arch using the first two eigenvalues, which accounted for 90% of the total shape change (P < 0.001). Supporting their role as aetiological factors, size and shape differences in dental arch morphology are found in patients with OSA.
The aim of the present study is to investigate nasal airway morphology in Asian adults with and without obstructive sleep apnea (OSA) using acoustic rhinometry (AR), principal components analysis (PCA), and 3-D finite-element analysis (FEA). One hundred eight adult Malays aged 18-65 years (mean ± SD, 33.2 ± 13.31) underwent clinical examination and limited channel polysomnography, providing 54 patients with OSA and 54 non-OSA controls. The mean minimal cross section area 1 (MCA1) and the mean minimal cross sectional area 2 (MCA2) were obtained from AR for all subjects and subjected to t tests. The OSA and control nasal airways were reconstructed in 3-D and subjected to PCA and FEA. The mean MCA1 and MCA2 using AR were found to be significantly smaller in the OSA group than in the control group (p < 0.001). Comparing the 3-D OSA and control nasal airways using PCA, the first two eigenvalues accounted for 94% of the total shape change, and statistical differences were found (p < 0.05). Similarly, comparing the nasal airways using FEA, the 3-D mean OSA nasal airway was significantly narrower in the OSA group compared to the control group. Specifically, decreases in size of approx. 10-22% were found in the nasal valve/head of inferior turbinate area. In conclusion, differences in nasal airway morphology are present when comparing patients with OSA to controls. These differences need to be recognized as they can improve our understanding of the etiological basis of obstructive sleep apnea and facilitate its subsequent management.
The aim of this study was to measure craniofacial morphology and nasal respiratory resistance (NRR) in Malay, Indian and Chinese subjects with obstructive sleep apnoea (OSA). The sample consisted of 34 male subjects, 27-52 years of age (Malay n = 11, which included five mild and six moderate-severe OSA; Indian n = 11, which included six mild and five moderate-severe OSA; and Chinese n = 12, which included six mild and six moderate-severe OSA) diagnosed using overnight polysomnography. After use of a decongestant, NRR was recorded using anterior and posterior rhinomanometry. Standardized lateral cephalometric radiographs were used to record linear and angular dimensions. Malay subjects with moderate-severe OSA had a shorter maxillary (sp-pm) and mandibular (gn-go) length when compared with a mild OSA reference sample (P < 0.05). The hyoid bone was located more caudally in the Chinese moderate-severe subjects (hy-NL, hy-ML)(P < 0.05), and may be a useful diagnostic indicator for severity in this racial group. No pattern of differences for NRR was seen between the moderate-severe and mild OSA subjects. The consistently lower values for nasopharyngeal resistance in all the moderate-severe subjects when compared with the mild group may indicate that some compensation at this level of the airway had taken place. Strong positive correlations between craniocervical angulation (NL/OPT) and total airway resistance and the turbulent component of flow (k(2)) suggest that head posture is sensitive to fluctuations in airway resistance (P < 0.01).
Repetitive hypoxia seen in obstructive sleep apnoea syndrome (OSAS) may affect bone metabolism increasing the risk for secondary osteoporosis. This study investigates the association between OSAS in children and secondary osteoporosis. This cross-sectional study included 150 children aged 10-17 years: 86 with OSAS and 64 with no OSAS. OSAS was confirmed by polysomnography. Quantitative ultrasound (QUS) of calcaneum measuring speed of sound (SoS) and broadband ultrasound attenuation (BUA) were collected. Other parameters collected including bone profile, vitamin D levels, physical activity scoring and dietary calcium intake. Majority were male and Malay ethnicity. OSAS children were mostly obese (84%) and 57% had moderate to severe OSAS. Most had lower physical activities scores. Mean (SD) phosphate and Alkaline phosphatase were lower in OSA children compared to controls: PO4, p = 0.039 and ALP, p