PubMed, the Cochrane Library electronic databases and Scopus were searched. Randomised controlled trials (RCT), prospective and retrospective studies with untreated controls and clinical trials comparing at least two treatment strategies conducted in the mixed dentition with unilateral or bilateral PDC were included. 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). Owing to heterogeneity in the study methods and unequivocal results, the scientific evidence was too weak to evaluate the effect of interceptive treatment on PDC or which treatment modalities are most effective. The quality of the studies is low due to inadequate sample selection and deficient description of sample size, confounding factors, uncertainty of randomisation and no blinding in measurements. 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.