Guided tissue regeneration, barrier membranes and reconstruction of the cleft maxillary alveolus.

The use of barrier membranes for bone regeneration is especially beneficial in the case of severely affected soft tissue. One useful indication may be the formation of an effective shell for bone grafts in maxilla cleft defect reconstruction. When selecting a proper material for clinical use, one must consider the safety record, the resorption time and route of elimination, the time of the maintained barrier function, the necessary time of mechanical strength, and costs. Two resorbable collagen membranes, one of single-layer and one of double-layer material, were tested in vitro and in vivo. The tested single-layer membrane is less expensive, but it is also less handling than the double-layer membrane. In vitro, samples were incubated in simulated surgical wound. A complete unambiguous picture of disintegration was not proved histologically in either material in six investigation terms (1-6 weeks). In vivo the effect of the assessed membranes was verified on a group of patients (N = 45) with a cleft. Materials were applied in the reconstruction of the alveolar defect by cancellous bone grafts. The influence on the course of healing was not stated as statistically significant. However, with respect to the costs of double layer membrane, this material was used in the most severe cases.