Size discrepancy of apical bases and treatment success in angle Class III malocclusion

The aim of this retrospective clinical study was to measure the apical bases and determine their size relationship in Class III malocclusion cases before and after orthodontic treatment, in order to evaluate their significance for the treatment success. Maxillary and mandibular apical bases were measured on study models of 104 Class III cases treated by conventional orthodontics, using a specifically constructed conveyance apparatus, and related to each other as an index. Treatment success was quantitatively assessed as the percentage change of PAR scores obtained from the pretreatment and posttreatment study models. Statistically significant relationships were disclosed between the measurements of the apical bases and several other evaluated parameters. The results obtained indicate a high prognostic value of the size relationship of the apical bases for the treatment success of Class III malocclusion.