The efficacy of calcium hydroxide for induced secondary dentin formation as a prophylaxis treatment for dens evaginatus

An occlusal tubercle fracture or attrition in dens evaginatus could be resulted in a pulpal disease. For the prophylactic treatment, a calcium hydroxide was used as a direct or an indirect pulp capping in order to stimulate secondary dentin formation. But some evidences suggested that it could also produce a small abscess in the pulp due to its alkaline properties, which may interfere a secondary dentin formation. Objectives: This study was to investigate the efficacy of calcium hydroxide on an indirect pulp capping and the rate of secondary dentin formation in dens evaginatus in vivo. Methods: Seven affected premolars, subjected to extract for an orthodontic reason, were used in this experiment. In each tooth, the tubercle was removed and the cavity, class I around 1.5mm deep, was prepared at the same area. The base of cavity was filled with a thin layer of calcium hydroxide (dycal®) and the rest was filled with an amalgam. The teeth were left in the mouth for 3 and 6 months. The ground section was prepared through the middle of the tooth with thickness of approximately 100-micron. The specimens were dehydrated in ethanol and then cleared by immerged in methyl salicylate overnight. The thickness of secondary dentine was examined and measured under a light microscope. Results: All teeth were reported no clinical sign of pulpitis or any periapical lesion at the day of extraction. Both groups showed substantially increased in the thickness of a secondary dentin. The mean value of 3 month group was 0.39mm (S.D. 0.11, n=4) and for 6 months group was 0.67mm (S.D. 0.21, n=3). Conclusion: The calcium hydroxide can be used for induced a secondary dentin formation in the prophylactic treatment of dens evaginatus.