Efficacy of 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 clinical studies that evaluated treatment with PMCs vs. amalgam control restorations in primary molars and provided data against which treatment outcomes 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 treatment 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 restorations. Overall, PMCs demonstrated greater longevity and reduced retreatment need compared with amalgam control restorations. The odds ratio for all studies fell within the boundary favoring treatment with PMCs. CLINICAL IMPLICATIONS Analysis of the literature, though mainly retrospective studies, demonstrated evidence of a more favorable outcome for PMCs than for amalgam restorations in primary molars requiring multisurface restorations.