Latero-lateral teleradiography as a predictive tool for the recovery time of impacted canines

Aim: The purpose of this retrospective study was to identify the relationship between specific cephalometric parameters measured on latero-lateral teleradiography and the time necessary for the forced eruption of canines impacted in the maxillary bone. Materials and Methods: The eruption times of 50 included canines were considered, for a total of 40 patients aged between 11 and 17 years. Each patient was banded with a fixed multibracket appliance (MBT prescription). The whale sample was subjected to the same protocol of surgical exposure of the included element and subsequent elastic orthodontic traction on an anchorage system. At the beginning of the treatment, each patient was asked for an orthopanoramic of the dental arches and a lateral teleradiography (taken from the CBCT), with related cephalometric analysis by Giannì. Specific angular and linear measurements were taken on the initial radiographs in order to determine the impacted canine’s position in the bone. Results: The results do not show correlation between the duration of mechanical eruption and the sex or age of patients at the time of surgery. Linear and angular teleradiographic parameters present poor correlation with traction time. Conclusions: the results of the present study show that the analysis on latero-lateral teleradiography do not present significant prognostic value for predicting treatment times in case of canine inclusion, especially the considered parametres. Radiographic evidence shows that impacted canines move approximately 1 mm per month during orthodontic traction. In any case, radiographic correlations with traction time prove to be an approximate predictive factor on the duration of treatment: the experience of the operator and the traction system used can modify the time required for the emergence of the canine, as well as the individual biological variables, bone density, cortical thickness and residual eruptive potential of the tooth. All these are factors that can accelerate or slow down the descent of the canine into the arch in addition to the radiographic position.