Sex differences in anthropometric and cephalometric characteristics in the severity of obstructive sleep apnea syndrome.

INTRODUCTION: Craniofacial anatomic abnormalities related to structural narrowing of the upper airway have been reported in patients with obstructive sleep apnea syndrome (OSAS). The purpose of this study was to test whether there are sex differences in the relative contributions of specific anthropometric and cephalometric measurements of OSAS severity. METHODS: The subjects were Taiwanese patients who visited the Ear, Nose, and Throat Department of National Taiwan University Hospital with complaints of snoring or sleep apnea. The anthropometric, cephalometric, and overnight polysomnographic records of 109 subjects were evaluated. RESULTS: There are obvious sex differences in the craniofacial skeletal characteristics that contribute to OSAS severity. Male patients with the following risk factors are likely to have more severe type OSAS: increased neck size, inferiorly positioned hyoid bone, and greater anterior lower facial height. The risk factors related to the severity of OSAS in female patients include smaller posterior facial height and anteriorly positioned hyoid bone. CONCLUSIONS: To evaluate OSAS severity, different anthropometric and cephalometric measurements should be used for men and women. The craniofacial skeletal characteristics that contribute to OSAS severity were in the anterior lower portion of the profile in men and in the posterior portion of the profile in women.

Cephalometric analysis of nonobese snorers either with or without obstructive sleep apnea syndrome.

OBJECTIVE: To determine if there is an indicator on the lateral cephalometric radiograph that can be used for the differential diagnosis of severe obstruct sleep apnea syndrome and simple snoring in nonobese young male adults. MATERIALS AND METHODS: The subjects were Taiwanese male patients with a complaint of snoring and/or sleep apnea, whose body mass index was less than 25 kg/m(2) and who were younger than 40 years old. Forty-six patients with severe obstructive sleep apnea and 36 patients with simple snoring were selected and underwent lateral cephalometric radiography, from which 24 linear and 34 angular measurements were calculated. Differences between the two groups were studied, and a discriminatory analysis was performed. RESULTS: Soft palate length, mandibular body length, tongue size, and distance from the hyoid bone to the mandibular plane were significantly larger in patients with severe obstructive sleep apnea syndrome. Of the original grouped cases, 76.5% were correctly classified using these five variables. The position of the hyoid bone in simple snorers was near the straight line from the third vertebra to the menton, whereas the position of the hyoid bone in severe obstruct sleep apnea syndrome patients was far below the line from the third vertebra to the menton. CONCLUSION: The position of the hyoid bone relative to the line from the third vertebra to the menton can be used as an indicator for a diagnosis of severe obstruct sleep apnea syndrome in nonobese young male Taiwanese adults.

Morphology of the palatal vault of primary dentition in transverse view.

The purpose of this study was to investigate the transverse view of the morphology of the palatal vault in the primary dentition at the primary second molar level. Observations were obtained from 150 dental stone casts of normal children (78 boys and 72 girls; aged four to five years). Palatal width, palatal depth, arch width, and primary second molar angulation were measured. There were no significant differences in palatal depth and primary second molar angulation between boys and girls or between the right and left sides. However, girls had a statistically significantly narrower upper dental arch width and palatal width than did boys. Palatal widths on the left side were statistically significantly larger than those on the right side for both sexes. Asymmetry in the palatal width greater than two mm was present in 21.8% of boys and 16.7% of girls. There was a correlation between buccal tipping in the upper primary second molar and greater palatal width.

Positional changes of the upper canine and posterior teeth, hard palate, and sinus floor from primary to permanent dentition.

This cross-sectional study investigated normal positional changes of the upper permanent canine and posterior teeth, hard palate, and sinus floor in normal Taiwanese children from the deciduous to early permanent dentition. In total, 261 panoramic radiographs were used. During the observation period, almost all structures changed their positions toward the distal and occlusal direction. The vertical positional changes of crowns of all teeth were greater than those of the root apices through all developmental stages. There were small positional changes in the mesial surfaces of the crowns of the upper buccal teeth until their roots had formed. There were continuous positional changes in the crowns and root apices of the permanent molars during tooth development and eruption. There were no significant changes in tooth inclination for any of the buccal teeth, whereas there were conspicuous changes in tooth inclination for the permanent molars. The floor of the maxillary sinus remarkably changed its position in an occlusal direction during the active eruption period of the first molar and buccal teeth.