In vivo evaluation of zinc oxide-propolis mixture as root canal filling material in the primary molars: A 24-month follow-up randomized controlled trial

Background Pulpectomy is a routine practice in children with pulpal and periapical infections, the success of which depends on the elimination of bacteria from the root canals. Propolis, a natural product with proven antibacterial and anti-inflammatory properties when mixed with zinc oxide powder as root canal filling material, it could provide good success in endodontic therapy of primary teeth. Aim The aim was to evaluate and compare the clinical effectiveness of zinc oxide-propolis mixture with zinc oxide eugenol (ZOE) as root canal filling material in nonvital primary molars. Settings and Design This was a 2-arm, parallel group randomized controlled trial with blinded outcome assessment. Materials and Methods Forty primary molars from children aged 4-8 years requiring pulpectomy treatment were randomly allocated into two groups according to the obturating material used: zinc oxide-propolis mixture (test group) and ZOE (control group). All the pulpectomy treated teeth were finally restored with stainless steel crowns, and the children were recalled at 6, 12, and 24 months for postoperative clinical and radiographic evaluation. Statistical Analysis Chi-square test was used to analyze the data. Results The overall success rate of pulpectomy with zinc oxide-propolis mixture and ZOE was found to be 95% and 70%, respectively, and the difference was statistically significant (P = 0.037). Zinc oxide-propolis mixture has shown a success rate of 100% at 6 months and 95% at 12 and 24 months follow-up, whereas ZOE has shown 80% success rate at 6 and 12 months, and it declined to 70% at 24-month follow-up. Conclusion Zinc oxide-propolis mixture demonstrated good clinical and radiographic success at the end of 24 months, and hence, it can be considered as an alternate root canal filling material in the primary teeth.