A meta-analysis of calcium silicate-based cements and calcium hydroxide as promoters of hard tissue bridge formation

Background The formation of a reparative hard tissue bridge is a key indicator of defensive pulp response and successful vital pulp treatment (VPT); however, there is a lack of comprehensive information regarding the impact of bioactive materials on hard tissue formation. Objectives This systematic review with meta-analyses aimed to evaluate the hard tissue bridge formation in direct pulp capping and pulpotomies in humans, comparing the use of ProRoot MTA with other calcium silicate-based cements (CSCs) and calcium hydroxide. Methods The search was conducted in six electronic databases, until May 2024. The selection process followed the PICOS criteria. Clinical trials that evaluated the hard tissue bridge formation in VPTs using ProRoot MTA compared with other CSCs or calcium hydroxide, were included. The quality of the studies was assessed using the RoB-2 tool for randomized clinical trials, and ROBINS-I for nonrandomized trials. Meta-analyses were performed to compare the frequency of complete bridge formation using RevMan software 5.3. The GRADE tool was used to determine the overall certainty of evidence. Results Twenty-six studies were included, and the majority showed high risk of bias. Meta-analyses revealed that using ProRoot MTA resulted in significantly higher frequency of complete hard tissue bridge formation compared with using other CSCs and calcium hydroxide. Subgroup analyses indicated that using ProRoot MTA led to higher complete bridge formation compared with Biodentine. The certainty of evidence was low. Conclusions The use of ProRoot MTA resulted in significantly higher frequency of complete hard tissue bridge formation, greater hard tissue thickness and better morphology compared with various other CSCs and calcium hydroxide. Almost all studies were performed in premolars extracted due to orthodontic reasons or third molars. This scenario does not represent the clinical setting and therefore results should be interpreted with caution.