| BackgroundWith the rapid development of Sleep Medicine, the effect of somnipathy on the growth and development of children has gained increasing attention, and at the same time, relative researches on somnipathy at home and abroad is growing gradually. The most common and serious somnipathy of children is obstructive sleep apnea hypopnea syndrome (OSAHS). OSAHS is caused by multiple factors. The abnormality of anatomy of the craniofacial soft tissues, the upper airway and the tissue around it plays an important role in the morphological etiology of the sleep apnea at night. In 1976, Guilleminault et.al summarize the basic characters of OSAHS of the adult, and yet they discover that children also have the problem of OSAHS.According to the guideline of orthodontic clinical diagnosis, sagittal skeletal pattern can be divided by ANB angle into three classes:classâ… , classâ…¡and classâ…¢skeletal pattern; vertical skeletal pattern can be divided by MP-SN angle into three groups:higher angle group, average angle group and lower angle group. The skeletal pattern perform an important role in the occlusionship, the position of soft and hard tissues, facial pattern, upper airway morphology and hyoid bone position and others. Therefore, researches on the correlations of skeletal pattern and morphology of the upper airway, hyoid bone position have drawn more and more attention from scholars both at home and abroad.Objective In order to study the correlations of skeletal pattern with upper airway morphology, hyoid bone position, the research has compared the differences in the upper airway morphology and hyoid bone position of male children with the different skeletal patterns. It aims to offer theoretical basis for orthodontic clinical diagnosis and treatment of OSAHS founded in children. At the same time, it will be able to serve as a reliable reference and provide evidence for the study on the craniofacial growth and development of children.MethodsThis study selected male children aged from 11 to 13 from the patient, who receive orthodontic treatment in Department of Orthodontics, School of Stomatology, Shandong University from 2007 to 2010, to carry out questionnaire, telephone interviews and clinical examination on sleep and respiration condition. Based on sample selected criteria,122 male children were selected as subjects of this study. The subject have received Cephalometric Roentgenogram Measurement (CRM) to measure skeletal-facial type, upper airway morphology and hyoid bone position. All the values are statistically analysed by the means of SPSS 16.0 (Statistic Package for Social Science). The statistical methods used in this study are ANOVA (one way analysis of variances) and multiple comparisons between groups (LSD), Pearson correlation analysis, Linear regression analysis. Through these statistic analysis, this research has made a comparison between upper airway morphology and hyoid bone position of children both with sagittal skeletal pattern and vertical skeletal pattern from Jinan.Results1. There are statistically significant differences among PNS-R, PNS-UPW, SPP-SPPW and V-LPW of male children both with sagittal skeletal pattern and vertical skeletal pattern in the early permanent dentition (p<0.05). The mean values tend to decrease as MP-SN angle decreases. The results of correlation and regression analysis reveal that there is a significantly minus relationship between MP-SN angle and SPP-SPPW, which means as the angle of MP-SN increases, the value of SPP-SPPW tends to decrease.2. There is no statistically significant difference among vertical positions of hyoid bone of male children with different vertical skeletal patterns in the early permanent dentition; by contrast, the difference of horizontal position of hyoid bone (H-S) is significant (p< 0.05). As MP-SN angle increases, the mean value of H-S is decreasing gradually. The results of the correlation and regression analysis reveal that there is significantly minus relationship between MP-SN angle and H-S which means as the angle of MP-SN increases, the value of H-S tends to decrease and the hyoid bone tends to occupy in a posterior position.3. There are statistically significant differences among SPP-SPPW, TB-TPPW, V-LPW of male children with different vertical skeletal patterns in the early permanent dentition (p<0.05). As ANB angle increases, the mean values of those index are decreasing gradually. The results of the correlation and regression analysis reveal that there are significantly minus relationships between ANB angle and TB-TPPW, V-LPW which means as ANB angle increases, the values of TB-TPPW, V-LPW tend to decrease.4. There is no statistically significant difference of the vertical position of hyoid bone of male children with different sagittal skeletal pattern in the early permanent dentition; by contrast, the difference of horizontal position of hyoid bone (H-S) is significant (p<0.05). As ANB angle increases, the mean value of H-S are decreasing gradually. The results of the correlation and regression analysis reveal that there is significantly minus relationship between ANB angle and H-S. That is to say, as ANB angle increases, the value of H-S tends to decrease and the hyoid bone tends to occupy a posterior position.ConclusionThere are statistically significant differences of upper airway morphology and hyoid bone position of children with different skeletal-facial patterns in Jinan. Furthermore, there are correlations of skeletal-facial pattern with the upper airway morphology and hyoid bone position, which influence the development of OSAHS in children. This research contributes to specify the etiology and causes of OSAHS. Orthodontic treatment as an effective method of intervention of children skeletal morphology, plays an important role in the prevention and interruption or treatment of OSAHS of children. |
