Vegetable polyurethane resin implant in cranioplasty - experimental study in rabbits

RESUMO

An experimental model was used to evaluate a new biomaterial - a vegetable polyurethane resin, extracted from castor plant oil - for repairing cranial vault bone loss. Two cranial, 15 x 10 mm in total width diameter and periosteum-free, bone failures were performed in 31 adult rabbits on both sides of the parietal region. Failures were not repaired in the 13 animals that comprised the control group and 18 animals had defects repaired using a vegetable polyurethane resin implant. Macroscopic, radiological and histological assessments were performed at 2, 6, 12, 18 and 24 post-operative weeks. Regardless of the method of evaluation, no tissue repair by bone neo-formation could be observed in the control group in which bone failures were replaced by scar tissue. In the group with implants, as of 6 weeks, repair of defects by bone neogenesis in peripheral areas was observed with a progressive favorable development in late samples (18 and 24 weeks), along with osteogenesis, osteoconduction and osteopromotion. Statistical analyses confirmed that bone healling in the implanted defects was more significantly effective (p<0.05). No toxic or reactional phenomena secondary to the presence of the implants that were not incorporated in the observational period were detected. No osteoinductive proprieties of implants became evident.