Efficacy of direct pulp capping for management of cariously exposed pulps in permanent teeth: a systematic review and meta‐analysis

BACKGROUND: The outcome of vital pulp treatment after carious pulp exposure is multifactorial and related to the procedure, biomaterial and pre-operative pulpal diagnosis. OBJECTIVES: To conduct a systematic review and meta-analysis determining the 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 randomized 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-randomized studies to be of fair and five of poor quality. Four randomized trials had a 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. The meta-analysis revealed MTA had better success than calcium hydroxide at 1-year (OR 2.66, 95% CI; 1.46- 4.84, P = 0.001) and 2- to 3-year 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 direct pulp capping in teeth with cariously exposed pulps with better long-term outcomes for MTA and Biodentine compared with calcium hydroxide.