A systematic review of the interceptive treatment of palatally displaced maxillary canines

The aim of this study was to assess whether interceptive treatment in the mixed dentition prevents impaction of palatally displaced canines (PDC) by systematically reviewing the literature. A literature search of PubMed, the Cochrane Library electronic databases, and Scopus was performed covering the period from January 1966 to May 2009. The inclusion criteria were mixed dentition with unilateral or bilateral PDC, randomized controlled trials (RCT), prospective and retrospective studies with untreated controls, and clinical trials comparing at least two treatment strategies. Three reviewers selected and extracted the data independently and evaluated the quality of the studies. Inter-examiner reliability was measured using the intraclass correlation coefficient (ICC). The search strategy resulted in 686 articles, of which two met the inclusion criteria. Because of the unequivocal results and heterogeneity in the study methods, the scientific evidence was too weak to fully evaluate the effect that interceptive treatment might have on PDC and which treatment modalities are most effective. The quality of the studies was rated as low because of inadequate sample selection and deficient description of sample size, confounding factors, uncertainty of randominization, and no blinding in measurements. The ICC value for total scores was >0.80, e.g. perfect agreement. To obtain reliable scientific evidence as to whether interceptive treatment prevents impaction of PDC and which treatment modalities are the most effective, better controlled and well-designed RCTs are needed. Future studies should also include assessment of patient satisfaction and pain experience as well as analysis of the costs and side-effects of treatments.