RESUMO
OBJECTIVES: To evaluate the effect of membrane occlusiveness and experimental diabetes on early and late healing following guided bone regeneration. MATERIAL AND METHODS: A total of 30 Wistar rats were randomly allocated to three groups: healthy (H), uncontrolled diabetic (UD) and controlled diabetic (CD). A critical size calvarial defect (CSD) was created at the mid-portion of one parietal bone, and it was treated with a double layer of e-PTFE membrane presenting 0.5 mm perforations. The animals were killed at 7 and 30 days of healing, and qualitative and quantitative histological evaluations were performed. Data were compared with the ones previously obtained from other 30 animals (10H, 10UD, 10 CD), where two CSDs were randomly treated with a double-layer e-PTFE occlusive membrane or left empty. RESULTS: Following application of cell occlusive or cell permeable membranes, significant regeneration can be observed. However, at 30 days in the H group occlusive compared to cell permeable membranes promoted enhanced bone regeneration (83.9 ± 7.3% vs. 52.5 ± 8.6%), while no significant differences were observed within the CD and UD groups. UD led to reduced regeneration compared to H when an occlusive barrier was applied, whereas comparable outcomes to H and CD were observed when placing perforated membranes. CONCLUSION: The application of cell permeable membranes may have masked the potentially adverse effect of experimental UD on bone regeneration. CLINICAL RELEVANCE: Membrane porosity might contribute to modulate the bone regenerative response in UD conditions. Future studies are needed to establish the degree of porosity associated with the best regenerative outcomes as well as the underlying molecular mechanisms.