Abstract Purpose: To assess the effect of a collagen matrix (Mucograft®) on the inflammatory process in a semi-critical experimental defect model in rats treated with bisphosphonates. Methods: Eighteen Wistar rats were randomly divided into three groups: saline (CG), alendronate (ALD) 5mg/kg (AG) or zoledronic acid (ZA) 0.2mg/kg (ZG). ALD was administered orally for 10 weeks and ZA was administered intravascula...