Different materials for direct pulp capping: systematic review and meta-analysis and trial sequential analysis

We systematically assessed randomized controlled trials comparing direct pulp capping materials. Trials comparing materials for direct capping and evaluating clinically and/or radiographically determined success after minimum 3 months were included. Two reviewers independently screened electronic databases (Medline, Central, Embase) and performed hand searches. Risk of bias was assessed and meta-analyses were performed, separated for dentition. Trial sequential analysis was used to assess risk of random errors. Strength of evidence was graded using the GRADE approach. From a total of 453 identified studies, 11 (all with high risk of bias) investigating 1094 teeth (922 patients) were included. Six studies were on primary teeth (all with carious exposures) and five on permanent teeth (carious and artificial exposures). Mean follow-up was 14 months (range 3-24). Most studies used calcium hydroxide as control, comparing it to mineral trioxide aggregate (MTA) (three studies), bonding without prior etching/conditioning (two), or bonding with prior etching/conditioning, enamel matrix proteins, resin-modified glass ionomer cement, calcium sulfate, zinc oxide eugenol, corticosteroids, antibiotics, or formocresol (each in only one study). One study compared MTA and calcium-enriched cement. In permanent teeth, risk of failure was significantly decreased if MTA instead of calcium hydroxide was used (risk ratio (RR) [95 % confidence intervals (CI)] 0.59 [0.39/0.90]); no difference was found for primary teeth. Other comparisons did not find significant differences or were supported by only one study. No firm evidence was reached according to trial sequential analysis. There is insufficient data to recommend or refute the use of a specific material. More long-term practice-based studies with real-life exposures are required. To reduce risk of failure, dentists might consider using MTA instead of calcium hydroxide (CH) for direct capping. Current evidence is insufficient for definitive recommendations.