Comparative evaluation of the efficacy of three methods of delivering calcium hydroxide into the root canal.

BACKGROUND: Calcium hydroxide, due to its favorable properties, such as an antimicrobial effect as well as its ability to dissolve necrotic tissues, inhibit tooth resorption and stimulate the formation of a hard tissue barrier, is widely used in root canal treatment. OBJECTIVES: The objective of this study was to compare the efficacy of 3 methods of delivery of calcium hydroxide into the canals. MATERIAL AND METHODS: This in vitro experimental study was performed on acrylic resin blocks with simulated curved canals (curvature of 24 degrees and 44 degrees ). Calcium hydroxide was delivered into the canals with 3 different instruments : a hand file, a Lentulo and a rotary file. The data was analyzed using the three-way analysis of variance (ANOVA) and Tukey's test. RESULTS: The density of calcium hydroxide was significantly different among the 3 groups (p < 0.001). The manual delivery technique resulted in the lowest and using a rotary file in the highest density of calcium hydroxide (p < 0.001). The mean density of calcium hydroxide was significantly higher in the canals with curvature of 24 degrees , irrespective of the delivery method (p < 0.001). The lowest mean density of calcium hydroxide was noted at 1 mm and 3 mm from the apex, whereas the highest mean density was noted at 11 mm from the apex, irrespective of delivery method (p < 0.001). CONCLUSIONS: A rotary file seems to be the most efficient instrument for delivering calcium hydroxide into the canals, especially into the apical region of canals with greater curvature.