锥束CT和曲面体层摄影在牛牙症诊断中的对比研究及在青少年中的发病率初探

The comparative study of cone beam CT and orthopantomography in the diagnosis of taurodontism and the primary exploration of its incidence in adolescents

目的:本研究旨在对比锥束CT和曲面体层摄影在牛牙症诊断中的准确性并初步探索牛牙症在青少年中的发病率。方法:选择于我院就诊的需要拔除磨牙的65名患者,年龄在25到60岁之间,共拔除40颗上颌磨牙,47颗下颌磨牙,在拔牙前分别拍摄曲面体层摄影和锥束CT(cone-beam computed tomography,CBCT),测量分析曲面体层摄影和锥束CT的牛牙症指数,最终与体外测量的离体牙牛牙症指数对比,以接近离体牙牛牙症指数的影像学方法作为更准确的诊断方法。随机抽取122名15~19岁青少年的CBCT测量磨牙牛牙症的发病率以及不同牙位之间的差异。结果:测量得出,上颌磨牙的牛牙症指数CBCT数据更接近离体牙(P>0.05),而曲面体层摄影数据结果显著小于离体牙测量结果(P<0.05),下颌磨牙三组牛牙症指数数据之间无显著差异(P>0.05)。使用CBCT测量122名青少年的第一、第二磨牙的牛牙症指数,发现人群发病率高达74.5%,牙体总发病率达40.0%。牛牙症指数在不同牙位中存在差异(P<0.01),从高到低依次是:上颌第二磨牙,下颌第二磨牙,上颌第一磨牙,下颌第一磨牙,且上颌磨牙的牛牙症指数明显高于下颌磨牙(P<0.01)。结论:牛牙症指数的测量时,相较于曲面体层摄影,采用CBCT测量可获得较准确结果。牛牙症在青少年中的发病率较高,且不同的牙位发病情况明显不同。

Objective: The study was to compare the accuracy of cone-beam computed tomography(CBCT) and orthopantomography in the diagnosis of taurodontism and to explore the incidence of taurodontism in adolescents.Method: 65 patients needing to have their molars extracted were selected in our hospital, aged between 25 to 50 years old, and a total of 40 maxillary molars, 47 mandibular molars were collected. Before the tooth extraction,orthopantomography and CBCT film was taken from the patients respectively, the taurodontism index was measured and compared with the taurodontism index of the extracted teeth eventually. The result closed to the extracted teeth is considered to be a more accurate diagnostic method. The CBCT of 122 adolescents aged 15 to 19 years was used to measure the incidence of taurodontism and the differences among molar positions. Results: CBCT data of maxillary molars were more similar to those of the extract molars(P>0.05), and the results of orthopantomography were significantly lower(P<0.05), there was no significant difference in the taurodontism index among the three groups in mandible molars(P>0.05). CBCT was used to measure the taurodontism index of 122 adolescents’ first and second molars. The incidence of taurodontism was as high as 74.5%, and the total incidence of molars was 40.0%. Taurodontism index was varied from different molar positions(P<0.01), from high to low was as follows: maxillary second molar,mandibular second molar, maxillary first molar, mandibular first molar, and the taurodontism index of maxillary molar was significantly higher than that of mandibular molar(P<0.01). Conclusion: In the measurement of taurodontism index,both the orthopantomography and CBCT can obtain more accurate results in the mandibular molars, while the CBCT can obtain more accurate results in the maxillary molars. Taurodontism is prevalent in teenagers, and the incidence is obviously discrepant in different molar positions. Dentists should pay more attention to the diagnosis and treatment of taurodontism.