Abstract
The purpose of this clinical investigation was to study the applicability of GBR technique to the large alveolar bone defects.
There were 30 subjects: Group Ⅰ;extraction socket of the mandibular retention third molar (12 cases), Group Ⅱ;extraction socket of retention tooth in the maxillary anterior tooth region (6 cases), and Group Ⅲ;bone defect after removal of radicular cyst (12 cases). The GBR technique using e-PTFE membrane (GORE-TEX Augmentation Material, oval-6®;GTAM) was applied to these alveolar bone defects. Clinical and radiological investigation, and histological study of the removed GTAM were performed. The mean implantation period of GTAM was 3 to 6 months.However, if early removal of exposed GTAM was performed, it was estimated at that time.
As a result, GTAM exposure with inflammatory reaction due to local infection occurred in 11 of 12 cases of Group Ⅰ, in 2 of 6 cases of Group Ⅱ, in 5 of 12 cases of Group Ⅲ. All GTAM exposure was found in the cervical region of adjacent teeth. Histological study demonstrated infiltration of bacteria into the porus structure of exposed GTAM. Incomplete bone regeneration was confirmed in 2 cases by means of dental X-ray examination at 22, or 26 weeks after application of GBR. On the other hand, bony healing was not found in any other cases, whose implantation period of GTAM was less than 18 weeks.
In conclusion, the large alveolar bone defects such as extraction sockets of the retention teeth or radicular cysts in the adjacent cervical region of neighboring teeth should be excluded from the indication of GBR. Moreover, a 3 to 6-month healing period was insufficient for the GBR of large alveolar bone defects.
