包头市蒙汉族青年正常[牙合]磨牙后间隙的CBCT研究

CBCT research on the space distal to the second molar between Mongolian and Han young adults with individual normal occlusion

目的探讨蒙古族和汉族青年男女磨牙后间隙之间的差异，从而评估蒙古族患者在正畸治疗时推磨牙向后进而保存28颗牙齿的自然牙列的可行性。方法于包头市各大高校中，随机选取符合纳入标准的蒙古族青年65名（男33，女32）和汉族青年65名（男33，女32），根据民族性别分为四组，对每一患者按同一标准拍摄CBCT；三维的重建后测量磨牙后间隙的长度、宽度、高度。结果同一个民族（蒙、汉族）青年第二磨牙后间隙大小与性别没有显著关系（P〉0．05）。蒙古族上、下颌第二磨牙后间隙长度、宽度均大于汉族，其差异有统计学意义（P〈0．05），而高度没有差异（P〉0．05）。结论蒙汉族青年第二磨牙后间隙存在显著差异，蒙古族青年在正畸治疗时采用推磨牙向后的矫治方案较汉族青年更为可行，可为蒙汉族青年差别正畸治疗提供参考。

Objective The purpose of this study was to analyze the difference of the space distal to the second molarbetween Mongolian and Han young adults so as to evaluate the feasibility of molar distalization. Methods 65 Mongolian and 65 Han undergraduates （33 males and 32 females, 18-25 year-old in each ethnic group） were randomly selected from Baotou city. They were divided into four groups according to the race and gender. CBCT was performed for every subject. The space distal to the second molar was measured. Results The space distal to the second molar had no significant difference between male and female in the same ethnic group （P〉0.05）. The length and width of the mandibular space distal to the second molar were greater in Mongolian than in Han adults （P〈0.05）. Conclusions The space distal to the second molar was greater in Mongolian than in Han adults. In Mongolian young adults, the third molar could be removed and molar distalization could be used to relieve crowding.