Reliability Of Two Methods In Maxillary Transverse Deficiency Diagnosis

ObjectiveTo evaluate the reliability of two methods(Andrews' element ? analysis and Yonsei CBCT transverse analysis)in maxillary transverse deficiency(MTD)diagnosis,and to give reference to the selection of the methods in MTD diagnosis.Materials and methodsPlaster casts and cone beam computed tomography(CBCT)images of eighty outpatients with skeletal Class ? malocclusion(twenty-nine males and fifty-one females,mean age of 20.16±8.22 years)were selected.Maxillary and mandibular width were measured respectively and independently by two examiners at an interval of two weeks,using Andrews' element ? analysis and Yonsei CBCT transverse analysis.The data were transported into SPSS and Medcalc software to calculate intra-class correlation coefficients(ICC)and to draw Bland-Altman Plots of intra-examiner and inter-examiner reliability.After diagnosis,the agreement of dichotomous diagnosis "MTD"and "not MTD" was evaluated with Kappa statistics in SPSS software.Results1.The ICC were all above 0.85,indicating good to excellent reliability.Compared with Andrews' element ? analysis,Yonsei CBCT transverse analysis had higher intra-examiner and inter-examiner intraclass correlation coefficients values in both maxillary and mandibular width measurements.2.In the Bland-Altman Plots of inter-examiner and intra-examiner reliability,Yonsei CBCT transverse analysis had equal or less outliers than Andrews element ? analysis.Apart from the bias in Yonsei CBCT analysis performed by examiner B,bias and confidence intervals of the Bland-Altman Plots of Yonsei CBCT transverse analysis were lower than that of Andrew' element ? analysis.3.There were nineteen samples with posterior insufficient overjet or crossbites.Using Andrews' element ? analysis,forty-two patients were diagnosed as MTD by examiner A and by examiner B.Thirty-one patients were diagnosed as MTD by examiner A and thirty-nine patients were diagnosed as MTD by examiner B,using Yonsei CBCT transverse analysis.The inter-examiner kappa values were 0.7 in Andrews' element ? analysis and 0.75 in Yonsei CBCT transverse analysis.For Andrews' element ? analysis,the intra-examiner kappa values were 0.62 in examiner A and 0.67 in examiner B;for Yonsei CBCT transverse analysis,the intra-examiner kappa values were 0.82 in examiner A and 0.80 in examiner B.The intra-examiner kappa values of Yonsei CBCT transverse analysis were all higher than those of Andrews element ? analysis.Conclusions1.Both Andrews' element ? analysis and Yonsei CBCT transverse analysis had good to excellent reliability and substantial diagnostic agreement.Yonsei CBCT transverse analysis had higher reliability in maxillary and mandibular width measurements and higher diagnostic agreement,compared with Andrews' element ?analysis.2.Posterior crossbites may not be the only reference in MTD diagnosis.Cautions need to be paid to the transverse dimension routinely in orthodontic diagnosis.