Agreement of the Newly Developed Moyers' Equations and Moyers' Tables

Abstract

OBJECTIVE: This study aimed to develop the Moyers' prediction equation to be used with tooth widths predicting app on smartphone. MATERIALS AND METHODS: Four equations were developed separately for sex and dental arches. Internal validation with Moyers' table was finished. External validation on 37 subjects with agreement test of both Moyers' prediction equations and Moyers' prediction tables was performed. STATISTICAL ANALYSIS: A general linear model procedure was used to create four prediction equations. Internal validation was evaluated using the coefficient of determination. External validation was performed using Bland and Altman (BA) test. RESULTS: Four equations were developed for OrthoAnalysis app on smartphone. The overall coefficient of determination of all equations and prediction table was 0.998 (p < 0.05) indicating good agreement of the two methods. The agreement test on the 37 subjects was that the BA test revealed the BA limits of agreement between the residuals of two predictions was -0.001 mm and ranged from -0.143 to 0.140 mm with almost all plots lying inside this difference interval. CONCLUSIONS: In summary, four novel estimation equations were developed and showed very low difference to the well accepted original Moyers' prediction tables. Therefore, the equations used in the orthodontic app for predicting unerupted tooth width were verified and valid for clinical use.