正畸治疗中下颌第二磨牙近中倾斜萌出相关因素的研究

目的 探讨正畸治疗过程中影响下颌第二恒磨牙近中倾斜萌出的因素。方法 选取78例正畸治疗患者,初诊时4个第二磨牙均未萌出,正畸治疗结束时,4个第二磨牙萌出建,且第二磨牙未经治疗。用Logistic回归分析正畸治疗后下颌第二磨牙近中倾斜发生与第三磨牙的牙胚存在与否、是否拔牙、下颌平面角、错类型、下颌牙弓前中段拥挤度、牙弓后段拥挤度和第一磨牙前移量之间的关系。结果 下颌第二磨牙近中倾斜与治疗过程中第一磨牙的前移量密切相关(P<0.001),其它因素排除在外,逐步回归方程为Y=1.153×第一磨牙前移量-2.855。结论 正畸治疗过程中过多前移第一磨牙,易导致第二磨牙近中倾斜。

Study on related-factors of mesioclination of lower second molars in treatment

Objective To investigate factors related to the mesioclination of lower second molars in treatment.Methods 78 orthodontic patients were enrolled in this study.The lower second molars of each subject did not erupt before orthodontic treatment and erupted after orthodontic treatment without any adjustment.Logistic regression was used to analyze the correlation between lower second molars mesioclination and seven factors（ the existence of third molar germ,treatment with or without extracting teeth,∠SN-MP,∠ANB, crowding of anterior arch,crowding of posterior arch and mesial movement of lower first molar） .Result Logistic regression revealed significant correlation between the mesioclination of lower second molars and the mesial movement of lower first molars（ P〈0.001） , when other factors were excluded.The regression equation is Y=1.153X-2.855.Conclusions The more first molars moved forward during the treatment,and the more mesioclination of lower second molar tended to occur.