This study was conducted to evaluate and compare the clinical efficacy of Zinc oxide-Propolis mixture with Zinc oxide Eugenol as root canal filling material in infected primary molars. This study is a randomized, double blind, trial comprising of 40 primary molars from the children aged 4-8yrs which were divided into two groups according to the obturating material used: Test group: Zincoxide-Propolis mixture; control group: Zinc oxide Eugenol. All the pulpectomy treated teeth were finally restored with stainless steel crowns and the children were recalled at 6, 12 and 24 months for post-operative clinical and radiographic evaluation to assess the success rate. The primary outcome measures were success at 24 months. The secondary outcome measures were success at 6 and 12 months. 

At 6 month follow-up, Zincoxide–Propolis mixture has shown 100% success, while Zincoxide Eugenol has shown a success of 80% and the difference was statistically significant(p= 0.035). At 12 month follow-up, Zincoxide–Propolis mixture has shown a success of 95%, while Zincoxide Eugenol has shown a success of 80%. At 24 month follow-up, Zincoxide–Propolis mixture has shown 95% success, while Zincoxide Eugenol has shown a success of 70% and the difference was statistically significant(p= 0.037). Zincoxide–Propolis mixture demonstrated good clinical and radiographic success at 24 months follow-up and hence it can be used as an alternate root canal filling material in primary teeth.