[Insertion of collagen matrix into open bony defects].

The use of collagen as a bone substitute was examined in a clinical study involving 70 patients. In a standardized operation impacted mandibular third molars were removed simultaneously. Collagen fleece was implanted in one osseous defect while the other defect was packed with iodoform gauze. Postoperative pain, swelling and complications were analyzed. There were significant differences between the two methods. The use of collagen fleece to obturate bony defects following surgical removal of impacked molars appeared to be of no advantage. On the contrary, there was a considerably higher rate of postoperative bleeding and complications. This could probably be related to the poor stability of the implanted material.