Propolis and commonly used intracanal irrigants. Comparative evaluation of inflammatory potential

The present study evaluated the inflammatory/irritant potential of propolis in comparison with commonly used intracanal irrigants such as chlorhexidine and calcium hydroxide, with normal saline solution as control using an animal (Wistar rats) model.

2% Evans blue was intravenously injected into the lateral caudal vein. 0.1 ml each of the test solutions was intradermally injected into the experimental sites designed on their shaved backs. The animals were then sacrificed after 1 1/2 and 3 hours respectively. Each piece of skin containing the injected solution was excised, immersed in 4 ml formamide and incubated at 45 degrees C for 72 hours. After filtration with glass wool, optical density(OD) was measured using a spectro-photometer and analyzed statistically.

At 620 nm irrespective of time, the mean optical density with Calcium Hydroxide was found to be maximum (0.197 +/- 0.095) while that with DMSO Propolis was found to be minimum (0.070 +/- 0.016). Both at 90 min and 180 min, the mean optical density with Calcium Hydroxide was found to be maximum.

On short-term evaluation, maximum inflammation was seen with calcium hydroxide followed by chlorhexidine and DMSO extract of propolis. Minimum inflammation was seen with sterile physiologic saline. With progress of time, maximum inflammation was seen with calcium hydroxide followed by chlorhexidine and DMSO extract of propolis which was non-significant.