Efficacy preformed metal crowns vs. amalgam restorations - In primary molars: A systematic review

Background. The authors evaluated the treatment efficacy of preformed metal crowns, or PMCs, vs, amalgam restorations in primary molars by means of a literature review and meta-analysis. Types of Studies Reviewed. From a literature search, the authors selected c linical studies that evaluated treatment with PMCs vs. amalgam control rest orations in primary molars and provided data against which treatment outcom es could be compared. Results. Ten studies with durations ranging from 1.6 to 10 years fulfilled the selection criteria. Their failure rates, based on need for subsequent t reatment or retention of the restoration at final evaluation, ranged from 1 .9 to 30.3 percent for PMCs and 11.6 to 88.7 percent for amalgam restoratio ns. Overall, PMCs demonstrated;greater longevity and reduced retreatment ne ed compared with amalgam control restorations. The odds ratio for all studi es fell : within the boundary favoring treatment with PMCs. Clinical Implications. Analysis of the literature, though mainly retrospect ive studies, demonstrated evidence of a more favorable outcome for PMCs tha n for amalgam restorations in primary molars requiring multisurface restora tions.