锥形束CT测量牙龈厚度准确性的初步研究

目的评价锥形束CT(CBCT)法测量牙龈厚度的可信度及准确性。方法选择20例牙龈健康者的120颗上颌前牙,采用CBCT法和牙龈穿刺法测量唇侧中央龈缘下2mm处牙龈厚度,比较两组差异并用Kappa系数评价两种方法的一致性;应用Kappa系数评价不同检查者用CBCT法测量牙龈厚度的一致性,以及组内相关系数ICC评价同一检查者重复测量数据的可信度。结果CBCT法测量牙龈厚度为(1.23±0.27)mm,牙龈穿刺法测量结果为(1.24±0.26)mm,差异无统计学意义(P>0.05),两组之间一致率为83.33%(Kappa=0.547)。不同的检查者CBCT法测量牙龈厚度的一致性检验Kappa系数为0.814,可信度良好(ICC=0.795),同一检查者CBCT法重复测量数据之间一致性检验Kappa系数为0.864,可信度良好(ICC=0.893);CBCT法对厚牙龈生物型具有高的灵敏度(92.05%)和低的特异度(59.38%)。结论CBCT测量牙龈厚度的结果与牙龈穿刺法的结果较一致,具有良好的可信度。

Preliminary study on the accuracy of gingival thickness measurement by cone beam CT

Objective To evaluate the reliability and accuracy of gingival thickness measurements by cone-beam computed tomography(CBCT).Methods A total of 120 maxillary anterior teeth from 20 periodontally health volunteers were recruited in this study.The transgingival method and the CBCT were used to measure the gingival thickness at the level of 2 mm apical to the gingival margin midbuccally.The difference was compared between the two methods.Intraoperator and interoperator reliability considering the measurement of CBCT were estimated with Cohen’s kappa coefficient,intraclass correlation coefficient(ICC).Results The agreement rate between CBCT and transgingival method was 83.33%,(Kappa=0.547).There was no statistically significant difference between the two methods.Different measurers used the CBCT method to measure the thickness of the gingival(Kappa=0.814,ICC=0.795)and the same measurer repeated measurement data showed good reliability(Kappa=0.864,ICC=0.893).CBCT method manifested high sensitivity(92.05%)and low specificity(59.38%)for definition of a thick biotype.Conclusion The measurement of gingival thickness with the use of CBCT is consistent with transgingival method and has high reliability.