Comparative evaluation of histological effect of calcium hydroxide and Portland cement on cat's dental pulp as direct pulp capping

Regardless of calcium hydroxide use as a pulp capping material, in many cases the results were questionable and unsuccessful. Recently the Portland cement has been introduced as a pulp capping material. The aim of this study was to compare the histological changes of cat’s dental pulp after capping with calcium hydroxide and Portland cement. Methods & Materials: This study was experimental and its technique was histological observation. Ten healthy, adults and coeval cats were selected. After keeping them in standard condition for two weeks, class III cavity on distal part of canine teeth was prepared and pulp was exposed. In each jaw, one pulp was covered with calcium hydroxide (A) and the other treated with Portland cement (B). Two cats were sacrificed after one week and the others were sacrificed after two months. Samples were assessed for severity at inflammation, dentinal bridge formation, necrosis, hyperemia and calcification. The data were analyzed by Mann-whitney U test. In one week samples were similar to each other. After two months, dentinal bridge formation was found in 3 samples (20 percent) of group (A) and in 9 samples (60 percent) of group (B). Inflammation was seen in 13 pulps (86.7 percent) of group (A) and 6 pulps (40 percent) of group (B). Necrosis areas in group (A) were found in 10 pulps (66.7 percent) and in 5 samples (33.3 percent) of group (B). Calcification was seen in 4 pulps (26.7 percent) of group (A) and in 6 samples of group (B). Also odontoblastic layer was seen in 3 samples (20 percent) of each group. Portland cement showed more dentinal bridge formation, less inflammation and necrosis in comparison with that of calcium hydroxide when used as a pulp capping material.