Resumen
OBJECTIVE: The aim of this study was to evaluate histologically the bio-degradation of two layers of Bio-Gide((R)) (BG) membrane, as compared with that of a single layer. MATERIAL AND METHODS: Two circular calvarial bony defects, 5 mm in diameter, were made in 24 Wistar rats. BG membrane, labeled with biotin, was cut into 5-mm-diameter disks, and placed in defects either as a mono-layer membrane (MLM) or as a double-layer membrane (DLM). Rats were sacrificed after 4 or 9 weeks and histology was performed. Membranes were stained with horseradish peroxidase-conjugated streptavidin and aminoethyl carbazole as a substrate for detection of biotinylated collagen. The area of collagen and thickness of the residual membranes were measured by image analysis software. Statistical analysis was performed using the non-parametric Wilcoxon's signed-ranks test. RESULTS: At 4-week collagen area per measurement window within the DLM sites (0.09+/-0.05 mm(2)) was significantly greater (P
