Introduction: A considered space analysis aims to predict the combined mesiodistal widths of unerupted permanent canine and premolars. A miscalculation can lead to the application of inadequate and irreversible treatments.
Objective: To assess the level of agreement between predictions generated by three methods (Moyers' predictive tables at the 50th and 75th percentiles and Tanaka-Johnston's equations) on the sum of unerupted teeth compared with measurements derived from cone beam computed tomography, considered in the present study as a 'gold standard'.
Materials and methods: The study sample was comprised of children (N = 26) aged 8-13 who visited the Department of Dentistry. Moyers' predictive tables and the Tanaka-Johnston equation were applied to ascertain the space requirements. Cone beam computed tomography was performed on each patient and the volumetric data analysed. A concordance correlation coefficient between each method's predictions was applied.
Results: The three methods tended to overestimate the cone beam computed tomography readings and were not able to entirely capture the variability of the sum of the unerupted teeth. Moyers' 50th percentile estimate revealed a more balanced distribution between over- and underestimation.
Conclusion: The present study suggested that Moyers' 50th percentile is the predictive method with the lowest absolute error and is preferred for clinical use.