Abstract
Guided bone regeneration (GBR) is an approach that induces osteopromotion through the regenerative membranes. These barriers exhibit bioactive behavior and mechanical function. Polydioxanone is a synthetic option, already used in medicine and dentistry, with good results in bone regeneration. This study aimed to evaluate bone repair in critical defects in rat calvaria using a polydioxanone membrane (Plenum(®) Guide) compared with a commercially available collagen-based membrane (Bio-Gide(®)). The bone defects were filled with Plenum(®) Osshp, a synthetic bone graft, hydroxyapatite:β-tricalcium phosphate, 70:30%, Group PG (Plenum(®) Guide + Plenum(®) Osshp), and Group BG (Geistlich Bio-Gide(®) + Plenum(®) Osshp). The specimens were submitted to immunohistochemical (RUNX2 and OPN), gene expression (RUNX2, IBSP, and VEGF), histometric, and microtomography analyses after 07, 15, 30, and 60 days postoperative. PG group showed greater immunolabeling area for RUNX2 and OPN, higher gene expression of VEGF (3.15 ± 0.85), and IBSP (24.9 ± 0.59). However, there was no statistical difference between groups in the histometric analysis regarding the percentage of connective tissue PG (0.83 ± 0.45), BG (0.70 ± 0.34), neoformed bone PG (0.60 ± 0.4), BG (0.65 ± 0.51), and remaining biomaterial PG (0.84 ± 0.31), BG (0.91 ± 0.33). In addition, there was no statistical difference between groups by micro-CT analysis. The absorbable-synthetic membrane, Plenum(®) Guide, is an effective membrane for guided bone regeneration.