上颌第一前磨牙根尖区根管横截面形态的研究

Study on transverse configurations of root canals in the apical part of maxillary first premolars

目的研究上颌第一前磨牙根尖区根管横截面的形态。方法选择15个上颌第一前磨牙(单根牙11个,双根牙4个),利用Isomet低速金刚砂切片机,在距解剖根尖1、2、3、4、5、6mm处垂直牙体长轴切割。然后在牙科手术显微镜下,利用Photoshop CS8.0软件测量各截面根管的颊舌径和近远中径,按标准记录根管横截面的形态。结果共获得切片111个,根管共138个,其中长椭圆形根管发生率为42.0%。单根管牙的颊舌径大于近远中径,以长椭圆形根管形态为主,其发生率向根尖降低;双根牙的颊根管颊舌径大多小于近远中径,但腭根管颊舌径均大于近远中径,长椭圆形根管发生情况更复杂。结论上颌第一前磨牙根尖区根管横截面形态复杂,可能影响根管治疗的质量。

Objective To investigate the transverse configurations of root canals in the apical part of maxillary first premolars. Methods Fifteen maxillary first premolars were used. Each root was horizontally sectioned at 1,2,3,4,5 and 6 mm from the anatomic apex by Isomet lowspeed silicon carbide section cutter. The buccal/lingual and mesial/distal diameters of canals were measured with Photoshop CS 8.0 software under a dental operating microscope. Results The percentage of long canals was 42.0%. In the single canal group,the buccal/lingual diameter was longer than the mesial/distal diameter,and the percentage of long canals decreased apically. In the two canals group,the buccal/lingual diameter was mostly shorter than the mesial/distal diameter in buccal canals,but longer in palatal canals,and the occurrence of long oval canals was different.Conclusions It is concluded that the tranverse configurations of root canals in the apical part of maxillary first premolars were complicated,and they influenced the quality of root canal therapy.