上颌第二乳磨牙MB2根管的临床发现率

Clinical study on the second mesiobuccal canal in the mesiobuccal root of the maxillary second primary molar

目的:研究上颌第二乳磨牙近中颊根第二根管(MB2)的临床发现率。方法:选择上颌第二乳磨牙患牙髓炎或根尖周炎的患儿73名共75个患牙,手术前后拍摄X线片。揭髓顶后用#10 K锉沿近中颊根根管口与腭根根管口之间的发育裂隙(沟)或暗线探查并寻找MB2,计算MB2发现率;记录近颊根根管(MB)与MB2的工作长度,并对数据进行统计分析。结果:75个上颌第二乳磨牙中有58个(77.33%)存在MB2,其中3个牙(5.17%)于髓室底水平有独立的MB2根管口。MB2发现率性别间无显著性差异(χ~2=0.89,P>0.05)。MB工作长度大于MB2工作长度(t=9.67,P<0.05)。结论:上颌第二乳磨牙中MB2有较高的发现率,临床治疗时应仔细探查。

AIM： To study the clinical incidence of the second mesiobuccal（ MB2） root canal of maxillary second primary molars.METHODS： 75 maxillary second molars with pulpitis or apical periodontitis in 73 children（ 34 male,39 female） were included.The teeth were examined by X-ray films before operating.After opening the pulp chamber,the fissure or grooves between the mesiobuccal and palatal canal were detected with #10 files to find MB2.Then,the therapy of MB2 was completed using root canal apex locator.The incidence of MB2 was calculate through the postoperative X-ray films.RESULTS： MB2 canal was found in 58 out of the 75 maxillary second primary molars（ 77.33%）.There was no significant defferenc of MB2 canal between gender（ χ^2= 0.89,P〉0.05）.The working length of MB was greater than that of MB2.CONCLUSION： There is a high incidence of the second mesiobuccal root canal of maxillary second primary molars.