The effect of antimicrobial photodynamic therapy mediated by papain gel on infected dentin in primary teeth: a clinical trial with microbiological evaluation

Purpose Antimicrobial photodynamic therapy (aPDT) has been used for treatment of dental caries. Papacarie™ is a gel composed of papain and chloramine employed for the partial removal of carious tissue, effective against bacteria; however, some studies report that this antibacterial action is not quite so evident. The aim of this study is to evaluate the clinical effect of the substance PapaMBlue followed by laser irradiation on infected dentin in dental caries lesion in primary teeth. Methods Thirty-two primary molars with deep occlusal dental caries were selected and divided in two groups: G1—caries removal with a low-speed drill—and G2—application of aPDT with PapacarieMBlue. After treatment, all the teeth were restored with glass ionomer cement and followed up clinically and radiographically, with evaluations at 3, 6, and 12 months. Dentin samples before and after treatment were analyzed microbiologically. Results A reduction in the bacterial count was found in both groups and the inter-group difference was non-significant ( p = 0.41022). Conclusion It is possible to conclude that there was a microbial reduction with the two treatments proposed; however, PapaMBlue is minimally invasive, maintains healthy tissue integrity, and is easy to use in Pediatric Dentistry and Public Health. Trial registration NCT02734420 on 10 March 2016