BIODEGRADABLE POLYGLYCONATE PLATES AND SCREWS - A HISTOLOGICAL-EVALUATION IN A RABBIT MODEL

Within the zygomatic arch, bilateral osteotomies were performed on 20 adult male New Zealand white rabbits. These were stabilized in an anat omical position with polyglyconate acid plates and screws. At 3, 4, 6, 9, and 12 months, rabbits were killed and their zygomatic complexes r emoved en bloc. Specimens were serially sectioned for standard histolo gical examination. Although no gross reactions were noted throughout t he course of this investigation, histological reactions were brisk. At 3 months, particulate material was surrounded by a foreign body giant cell-type reaction. The quantity of foreign material appeared to decr ease by 4 months, at which time the foreign body reaction was partiall y replaced by fibrous tissue. By 6 months, there was a thick periostea l scar at the osteotomy site with a few islands of persistent foreign material. These were primarily seen in small, irregular vesicular spac es surrounded by a large number of histiocytes with their characterist ic foamy cytoplasm. Although this foreign body reaction had subsided b y 12 months, small foci of chronic inflammation still persisted.