冠周炎的发生与下颌第三磨牙位置的相关研究

Correlation study of pericoronitis and position of mandibular wisdom tooth

目的探讨下颌第三磨牙的位置与冠周炎发生间的关系。方法选择434例患者的450颗下颌第三磨牙为研究对象。将450颗下颌第三磨牙分为冠周炎组(Ⅰ组)和无冠周炎组(Ⅱ组),分别记录两组下颌第三磨牙的阻生类型、磨牙后垫高度和倾斜度、冠周盲袋深度及龈瓣大小,并将两组牙的以上数据进行统计学分析。结果冠周炎组下颌第三磨牙与无冠周炎组下颌第三磨牙比较,前者磨牙后垫更高、倾斜度更大、盲袋更深、龈瓣面积更大;而两组下颌第三磨牙的阻生类型比较则无明显差异。结论冠周存在深盲袋、大龈瓣,高而倾斜的磨牙后垫是下颌第三磨牙高发冠周炎的危险因素,此类下颌第三磨牙可行预防性拔除。

Objective To study the relationship between the position of mandibular wisdom tooth and pericoronitis. Methods 450 mandibular wisdom teeth of 434 patients were collected and studied. 450 mandibular wisdom teeth were divided into two groups. One was pericoronitis group （group Ⅰ ）, the other was no pericoronitis group （group Ⅱ ）. Impacted type of mandibular wisdom tooth, the depth of pericoronal pockets and the size of gingival flaps, the height and gradient of retromolar pads were recorded. The data in the two groups was analysis statistically. Results Compared with the mandibular wisdom tooth in the no pericoronitis group, the retromolar pad was higher and more oblique, pericoronal pocket was deeper and size of gingival flap was bigger in the pericoronitis group. But no difference was observed in type of impaction between two groups. Conclusion It was the danger factors of pericoronitis occurrence that deeper pericoronal pocket and bigger gingival flap surrounding mandibular wisdom tooth, heighter and more oblique retromolar pad, which was served as the criterion of prophylactic wisdom tooth extraction.