COMPARISON OF CALCIUM-PHOSPHATE CEMENT MIXTURE AND PURE CALCIUM HYDROXIDE AS DIRECT PULP-CAPPING AGENTS

Calcium phosphate cement (CPC) and pure calcium hydroxide were used as direct pulp-capping agents on the deliberately exposed pulp tissue of 60 teeth in five monkeys. Their effects on the pulp tissue of individ ual teeth were observed and histologically compared after 12, 20 and 2 4 weeks. The results showed that both materials produced similar respo nses with regard to their biocompatibility and induction of hard tissu e barrier formation. Vasodilatation, chronic inflammation and calcific ation nidi scattered within the pulp tissue of the 12-week group were observed. Twenty weeks after application of capping materials, a crude reparative dentinal bridge with inclusion of soft tissue or bulky cap ping agents appeared. A more mature, hard tissue barrier with a better degree of mineralization and formation of dentinal tubules was demons trated in the 24-week group. The above findings associated with the ab ilities of self-setting and fair compressive strength suggest that CPC appears superior to pure calcium hydroxide and may have potential for clinical application, although many issues remain to be further inves tigated.