BACKGROUND: The outcome of vital pulp treatment after carious pulp exposure is multifactorial and related to the procedure, biomaterial and preoperative pulpal diagnosis. OBJECTIVES: To conduct a systematic review and meta-analysis determining outcome of direct pulp capping (DPC) in mature permanent teeth with a cariously exposed pulp and a clinical diagnosis of reversible pulpitis, and ascertain whether the capping material influences the outcome. METHODS SOURCES: MEDLINE Ovid-SP, Cochrane Central-Register of Controlled-Trials (CENTRAL), International Clinical Trials Registry Platform (ICTRP), ClinicalTrials.gov, Embase, and Web of Science until April 2020. Inclusion: Prospective, retrospective cohort studies and randomised trials investigating DPC outcome or comparing different capping materials after carious pulp exposure. Exclusion: Primary teeth, mechanical, traumatic or not-specified pulp exposure, teeth with irreversible pulpitis or no pulpal diagnosis. Risk of bias assessed using Cochrane and modified-Downs and Black quality assessment checklist. Meta-analysis on combined clinical/radiographic outcome was performed using a random effect model. Success was defined as absence of signs and symptoms of irreversible pulpitis, apical periodontitis or loss of pulp vitality. RESULTS: Quality assessment highlighted four non-randomised studies to be of fair and five of poor-quality. Four randomised trials showed high risk of bias. The pooled success rate differed based on material and follow-up. Calcium hydroxide success rate was 74% at 6-months, 65% at 1-year, 59% at 2-3 years and 56% at 4-5 years. Mineral trioxide aggregate (MTA) success was 91%, 86%, 84% and 81% at the same time points. Biodentine success was 96% at 6-months, 86% at 1 year and 86% at 2-3 years. Meta-analysis revealed different MTA had better success than calcium hydroxide at 1-year (OR 2.66, 95% CI; 1.46- 4.84, p=0.001) and 2-3 years follow-up (OR 2.21, 95% CI; 1.42 - 3.44, p=0.0004). There was no difference between MTA and Biodentine.
DISCUSSION: These results were based on poor methodological quality studies. The effect size for of MTA vs Ca (OH)2, although modest, was consistent with narrow CI.
CONCLUSIONS: Low-quality evidence suggests a high success rate for DPC in teeth with cariously exposed pulps with better long-term outcomes for MTA and Biodentine compared to calcium hydroxide.