【摘要】 目的:观察并测量两种不同牙根形态的下颌第二磨牙根管横断面最小根管壁厚度。方法:使用改良B ranm ante体外模型,将具有C形牙根(C组)或两个独立牙根(S组)中国人下颌第二恒磨牙各22颗,在距根尖3,5.5,8 mm处将样本锯为四段,观察C形根管横断面形态,测量断面最小根管壁厚度。结果:在牙体长轴水平,C组三个根管横断面形态不相同比例为63.6%(14/22),最薄根管位于C组的第2个断面,壁厚为(0.66±0.20)mm。结论:具有C形根管下颌第二磨牙的根管壁较薄,根管治疗时要注意预防。更多还原

【Abstract】 Objective To observe the cross-sectional anatomy of mandibular second molars with two different root kinds and measure the thickness of the minimum root canal wall.Methods A modified Bramante muffle was used and 22 chinese mandibular second molars with C-shaped root(group C) or seperated roots(group S) were sectioned into four pieces perpendicularly distance from apex to 3,3.5,8 mm,respectively.The cross-sectional anatomical morphology was observed and the minimum root canal wall thickness(MWT) of each section was measured.Results At the longitude level,14 teeth(63.6%) were lack of unanimous morphology of the three cross sections in group C,the thinckness of section two in group C was the thinnest one and only(0.66±0.20)mm.Conclusion More attention should be paid to the root canal treatment in mandibular second molars with C-shaped canal because of its thin root canal wall.更多还原