Does interceptive extraction of multiple primary teeth increase the chances of spontaneous eruption of permanent maxillary canines positioned palatally or centrally in the alveolar crest? A Systematic review.

INTRODUCTION:Extraction of primary maxillary canines in the mixed dentition has been suggested to increase the rate of normal eruption of displaced permanent canines (DPCs). In this study we assessed whether extracting multiple primary teeth increases the rate of normal eruption of DPCs positioned palatally or centrally in the alveolar crest. METHODS:Unrestricted searches in 8 databases were performed up to March 2021. We looked for data on the prevalence of physiologic eruption of DPCs and the changes in their position from randomized controlled trials. The risk of bias was assessed using the Cochrane Risk of Bias 2 Tool. Exploratory synthesis was carried out using the random effects model. RESULTS:Three studies (at low risk of bias) were identified, involving 128 individuals, followed for up to 48 months. The double extraction did not result in a benefit regarding successful eruption at 24 months follow-up, nor the change in position after 14.8 months. However, after 48 months the double extraction was beneficial (Risk Ratio: 1.17; 95% Confidence Interval: 1.05 to 1.30, P=0.005). Moreover, after 18 months, the DPCs' position improved more in the double extraction sites. CONCLUSIONS:While the extraction of the deciduous canine and first molar does not increase the chance of normal eruption nor improves the position of DPCs in shorter follow-ups, it might confer a benefit after a longer period of observation. Further studies are warranted in order to clarify the magnitude and clinical significance of any potential benefit and provide guidance to clinical decisions.