Double vs Single Primary Teeth Extraction Approach as Prevention of Permanent Maxillary Canines Ectopic Eruption

PURPOSE: To compare the effects of extraction of primary maxillary canines and first molars (double extraction approach) vs primary maxillary canines extraction (single extraction approach) in cases of ectopic permanent maxillary canines (PMCs). METHODS: Palatally or centrally displaced PMCs were randomly assigned as follows: single extraction (Group 1=29 patients, 52 canines); double extraction (Group 2=30 patients, 56 canines). PMCs inclination to the midline and to the long axis of the lateral incisor, mesiodistal position of the PMCs crown, and first premolars angulation to the midline were measured on panoramic radiographs at T0 and after 18 months (T1), on average. Between-group statistical comparison was carried out on T0-T1 changes for all the radiographic variables. Eruption/noneruption of the PMCs was also assessed. RESULTS: Group 2 exhibited improvements in PMCs intrabony position among all the examined variables (P<.001), obtaining a greater parallelism between the roots of the PMCs and the adjacent lateral incisors (P<.001). An improved position of the first premolars due to a reduced angulation (P<.001) was also observed. Clinical success rates showed no statistically significant difference. CONCLUSIONS: The double extraction approach proved to be a more effective procedure vs the single extraction approach in improving permanent maxillary canines' intraosseous position.