下颌第三磨牙缺失、阻生及与错(牙合)畸形关系研究

Study on the Relationship between Mandibular Third Molar Loss, Impact and Malocclusion

目的研究内蒙古地区下颌第三磨牙缺失、阻生及其与各类错[牙合]畸形关系。方法方便选择2009年1月—2014年12月内蒙古医科大学第四附属医院口腔科符合要求的患者1065例,年龄在25~35岁。进行分类统计。结果①骨性Ⅰ类错[牙合]571例,占53.62%,Ⅱ类错[牙合]301例,占28.26%,Ⅲ错牙合193例,占18.12%。②骨性Ⅰ类错[牙合]下颌第三磨牙以垂直阻生为主,Ⅱ类以下颌第三磨牙缺失为主,Ⅲ类以下颌第三磨牙近中阻生为主。③各类错[牙合]第三磨牙萌出情况χ^2比较差异有统计学意义。结论3种错[牙合]畸形的下颌第三磨牙正萌率均较低。骨性Ⅰ类错[牙合]下颌第三磨牙垂直阻生较常见;骨性Ⅱ类错[牙合]下颌第三磨牙缺失比其它两组明显;骨性Ⅲ类错[牙合]下颌第三磨牙以近中和水平阻生多见。因而得出第三磨牙的存在状况与错[牙合]畸形的类型有一定的关系。可根据早期错[牙合]畸形的类形监测第三磨牙的存在状况,及时做出合理的处理。

Objective To study the loss and impact of mandibular third molars in Inner Mongolia and its relationship with various malocclusions. Methods A total of 1 065 patients with the requirements of the Department of Stomatology of the Fourth Affiliated Hospital of Inner Mongolia Medical University from January 2009 to December 2014 were conveniently selected, aged 25-35 years, and performed classification statistics. Results 1.571 cases with skeletal class Ⅰ malocclusion, accounting for 53.62%, 301 cases with class Ⅱ malocclusion, accounting for 28.26%, and 193 cases with Ⅲ malocclusion, accounting for 18.12%. 2.The skeletal class Ⅰ malocclusion combined with the mandibular third molar was mainly caused by vertical impact. The type Ⅲ jaw and the third molar were mainly missed, and the type Ⅲ lower jaw molar was mainly affected by the middle and middle impact. 3. All kinds of malocclusion and third molars eruption χ^2 comparison were statistically significant. Conclusion The positive rate of the mandibular third molars with three malocclusions is low. The vertical impact of the skeletal class Ⅰ malocclusion combined with the mandibular third molar is more common;the skeletal class Ⅱ malocclusion combined with the mandibular third molar is more obvious than the other two groups;the skeletal class Ⅲ malocclusion combined with the mandibular third molar with near-neutral level It is more common to block. Therefore, it is concluded that the existence of the third molar has a certain relationship with the type of malocclusion. The presence of the third molar can be monitored according to the type of early malocclusion, and reasonable treatment can be made in time.