成人骨性Ⅲ类错牙合患者不同垂直骨面型基骨及牙弓宽度的特征

Characteristics of basal bone and dental arch width of skeletal classⅢmalocclusion adults with different vertical facial types

目的:应用锥形束CT(CBCT)测量分析成人骨性Ⅲ类错牙合基骨及牙弓的宽度特征及其与垂直骨面型的相关性。方法:选取成人骨性Ⅲ类错牙合患者66例,根据前颅底平面和下颌平面的交角(SN-MP)分为低角组(SN-MP<29°,n=22)、均角组(29°≤SN-MP≤38°,n=22)和高角组(SN-MP>38°,n=22),进行CBCT扫描,测量上下颌基骨及牙弓宽度。结果:上下颌基骨宽度在不同垂直骨面型组间表现为高角组<均角组<低角组,3组间上下颌基骨宽度差、上下颌牙弓宽度及上下颌牙弓宽度差差异均无统计学意义(P>0.05)。上下颌基骨宽度和SN-MP角呈负相关关系(r=-0.459、-0.494,P均<0.05)。结论:上下颌基骨宽度相较于牙弓宽度与垂直骨面型的相关性更强,骨性Ⅲ类错牙合患者在正畸治疗时更应关注基骨与垂直骨面型的联系。

Aim:To measure and analyze the width characteristics of the basal bone and dental arch in skeletal classⅢmalocclusion adults by using cone-beam computed tomography(CBCT)images,and to analyze the correlation between the characteristics and the vertical facial types.Methods:Sixty-six adults with skeletal classⅢmalocclusion were selected.According to the intersection angle between the sella-nasion plane and the mandibular plane angle(SN-MP),they were divided into hypodivergent group(SN-MP<29°,n=22),normodivergent group(29°≤SN-MP≤38°,n=22)and hyperdivergent group(SN-MP>38°,n=22),CBCT scans were performed to measure the width of the maxillomandibular basal bone and dental arch.Results:The maxillomandibular basal bone width in different vertical skeletal type groups was as follows,hyperdivergent group<normodivergent group<hypodivergent group.There were no significant differences in the maxillomandibular basal bone width discrepancies,the maxillomandibular dental arch width,or the maxillomandibular dental arch width discrepancies among the three groups(P>0.05).The maxillomandibular basal bone width was negatively correlated with SN-MP angle(r=-0.459,-0.494,P<0.05).Conclusion:The maxillomandibular basal bone width has a stronger correlation with the vertical facial type than the dental arch width.Skeletal classⅢmalocclusion patients should be paid more attention to the relationship between the basal bone and the vertical facial type during orthodontic treatment.