Mixture of epsilon-caprolactone-lactide copolymer and tricalcium phosphate: a histological and immunohistochemical study of tissue reactions

In cranio-maxillofacial surgery, bone transplantation is needed for treatme nt of bony defects. An autograft, allograft or biomaterial can be used. Aut ogenous bone grafts are considered to be the best materials available, but there are some disadvantages in their use including donorsite morbidity, ne ed for a second operative site and limited graft supply. A search for new b one-graft materials therefore remains necessary. We prepared a mixture of t ricalcium phosphate (TCP), which is a resorbable, non-toxic, osteoconductiv e ceramic material and epsilon-caprolactone-lactide copolymer P(epsilon-CL/ DL-LA), a resorbable polymer, and placed it in the dermis and in mandibular bone defects in 13 rabbits. Follow-up times were two, three, seven, eight, 12, 15 and 18 weeks, tissue reactions were assessed, histologically and im munohistochemically. Times of resorption of the material from tissues were reported. We found that the mixture caused a mild inflammatory reaction whe n placed in bone and severe inflammation when placed in dermis. No highly f luorescent layer of tenascin or fibronectin was found surrounding the impla nt area. The mixture was excellent to handle and very easy to place into bo ne defects. The results are promising and have led us to continue developme nt of the mixture. (C) 1999 Kluwer Academic Publishers.