Clinical and histologic observation of replacement of biphasic calcium phosphate by bone tissue in monkeys.

Biphasic calcium phosphate, consisting of beta-tricalcium phosphate and hydroxyapatite, was implanted in wide and deep periodontal osseous defects of monkeys in combination with the guided tissue regeneration technique. After 12 weeks, sites treated with a combination of biphasic calcium phosphate and guided tissue regeneration maintained the shape of the ridge, but both guided tissue regeneration and control sites (untreated) showed extreme resorption. A histopathologic investigation revealed that numerous macrophages contained small particles of ceramic within their vesicles and the active bone replacement occurred from the surrounding bone. Biphasic calcium phosphate has osteoconductive potential and this potential may be related to degradation by macrophage phagocytosis.