Improvement of Peri-Implant Repair in Estrogen-Deficient Rats Fed a Cafeteria Diet and Treated with Risedronate Sodium

Simple Summary Postmenopausal osteoporosis, characterized by an imbalance in the remodeling cycle in which bone resorption exceeds bone formation, affects a large part of the population seeking rehabilitation with osseointegrated implants, making the prognosis of these patients unfavorable. It is estimated that approximately 99 million people over the age of 50 were diagnosed with osteoporosis in the United States in 2010. A range of drugs are used for the treatment of postmenopausal osteoporosis, aiming to prevent skeletal fractures in individuals with this osteometabolic disorder. Bisphosphonates are widely prescribed drugs to increase bone mineral density (BMD) and decrease the risk of skeletal fractures in patients with osteoporosis, with good results in this regard. However, little attention has been paid to the impact that the mechanism of action of this drug generates on the bone repair process, and more scientific evidence is needed to better understand the role of this drug in the peri-implant repair process. (1) Background: Postmenopausal osteoporosis combined with an unhealthy lifestyle can lead to the development of metabolic syndrome, a common condition in individuals requiring oral rehabilitation. Bisphosphonates are used to increase bone mineral density. However, further studies are needed to evaluate the action of this drug on the bone repair process in the jaws. The aim of this study was to evaluate the peri-implant repair of rats with estrogen deficiency and metabolic syndrome treated with risedronate sodium. (2) Methods: Twenty-four female Wistar rats were divided into three groups: SHAM: sham surgery; OVX/SM: ovariectomy combined with a cafeteria diet; OVX/SM/RIS: ovariectomy associated with a cafeteria diet and treatment with sodium risedronate. After 30 days, the animals underwent extraction of the upper first molars. Thirty days after the extraction, an implant was installed in the same region. Sixty days after the implant was installed, the animals were euthanized for biomechanical analysis and confocal microscopic analysis. After confirming the normal distribution of the sample data, a one-way ANOVA test was performed, followed by Tukey's post-test, with a 5% significance level. (3) Results: Significant bone preservation was observed in the risedronate-treated group. Higher removal torque values were obtained by the risedronate-treated group. (4) Conclusions: Better biomechanical performance of the implants installed in the animals treated with risedronate sodium was observed.