EVALUATION OF THE OSTEOGENIC POTENTIAL OF BIOMATERIALS IMPLANTED IN THE PALATAL CONNECTIVE-TISSUE OF MINIATURE PIGS USING UNDECALCIFIED SECTIONS

Calcium phosphate or calcium carbonate biomaterials are widely used as bone substitutes in periodontal surgery. This study evaluates the ost eogenic potential of five different alloplastic biomaterials implanted in the connective tissue of the palatal papilla in miniature pigs. A porous hydroxyapatite (PHA), a dense hydroxyapatite (DHA), a semi-poro us hydroxyapatite (SPHA), a tricalcium phosphate (TCP) and a calcium c arbonate natural coral (NC) were implanted in a tunnel in the palatal papillae of seven miniature pigs. Undecalcified sections were examined histologically at 1, 2, 3, 4, 8, 12 and 24 wk intervals. Resorbable m aterials (TCP and NC) were totally resorbed by 24 wk. DHA, PHA and HA showed very limited resorption, although there were multinucleated gia nt cells in contact with PHA and SPHA. There was no histologically det ectable bone formation in contact with or near any of the biomaterials tested. However, several particles of NC, and sometimes of PHA, were surrounded by a dense, mineralized matrix. It is concluded that none o f these biomaterials, in their presently available forms, has any bone inducing capacity.