Beneficial therapeutic effects of sildenafil on bone healing in animals treated with bisphosphonate

Abstract

Objectives: The purpose of the present study was to evaluate the effects of sildenafil on mandibular fracture healing in animals treated with zoledronic acid by using histologic, histomorphometric, immunohistochemical, and radiodensitometric
methods.

Materials and Methods: A total of 36 Sprague–Dawley rats (3 months old) were used. All animals were treated intraperitoneally with 0.1 mg/ kg zoledronate three times per week, for a total of 8 weeks. Postoperatively, the animals were divided into two groups: zoledronate group (Z), which had no treatment applied (n = 18), and zoledronate + sildenafil (ZS), which were treated daily with 10 mg/kg sildenafil (n = 18). Each group was divided into two subgroups and the animals were sacrificed at the end of week 1 (Z1 and ZS1, n = 9) and week 4 (Z4 and ZS4, n = 9) after the operation. Histologic, histomorphometric, immunohistochemical analysis, and radiodensitometry were performed on the test subjects.

Results: Sildenafil-treated groups showed a significant increase in fracture healing scores. This result was supported by the densitometric, histologic, histomorphometric, and immunohistochemical findings.

Conclusions: Sildenafil may have positive effects on accelerating and improving fracture healing, and it may be used as a supporting factor in bone healing in patients treated with bisphosphonate (BP) to prevent negative effects of BP's

Keywords: bisphosphonate, bone healing, fracture healing, osteonecrosis, sildenafil, zoledronic acid