the effects of propolis on discolouration of teeth

objective: propolis is a resinous material produced by honeybees that has recently gained fame as an antimicrobial agent. this study sought to assess the effects of propolis as an intra-canal medicament on tooth discoloration. the effect of its application technique on the degree of discoloration was investigated as well. methods: this experimental study was conducted on 40 intact anterior human teeth. after access cavity and canal preparation, the teeth were randomly divided into three groups. in group a, propolis was placed inside the canals and pulp chamber. in group b, propolis was used as an intracanal medicament. group c was considered as the control group and saline solution was injected into the canals. labial surfaces of all teeth were digitally photographed using a digital camera (fujifilm at one day, one week, 2 weeks, one month and 2 months time points. color of teeth was assessed and measured at incisal, middle, and cervical segments using the cielab system and photoshop software. collected data at different time points were statistically analyzed. results: the overall color change in the two groups of a and b was significantly different from the control group (p<0.001). significant changes in color were also noticed in follow up sessions in groups a and b (p<0.001). at 2 months, the difference in overall color change between incisal, middle and cervical thirds of teeth in groups a and b was not statistically significant. conclusion: based on the obtained results, application of propolis as an intracanal medicament can lead to clinical color changes in tooth crown. its application technique has no effect on the degree of discoloration.