ACKGROUND: Simvastatin (SIM), a pharmacological drug used for hypercholesterolemia, has been found to have pleotropic effects on bones. Simvastatin together with the appropriate carrier may decrease bone loss around implants.

PURPOSE: To compare the long term effects of autologous PRF alone, and PRF loaded with SIM on peri-implant bone changes and implant stability in patients undergoing implant rehabilitation.

MATERIALS AND METHODS: A randomized controlled split-mouth studyincluding 8 males between the ages of 45-60 years. Each patient received two implants, one on each side of the arch. One side was treated with PRF alone and the other side with PRF +Simvastatin, at the time of Osteotomy. A cone-beam CT was used to evaluate bone changes around the insertion of implant sites atthree, six, and twelve months postoperatively. The secondary outcome included measuring implant stability using Ostell device at baseline and 3 months post insertion. To compare groups at different time periods, data was examined using a two-way (ANOVA) analysis.

Inclusion Criteria:

• patients with a partially edentulous mandible indicated for rehabilitation with implant prostheses,
• any extractions, or surgeries performed at least six months earlier.

Exclusion Criteria:

• patients with systemic diseases affecting bone quality or resorption
• temporomandibular joint dysfunction,
• severe attrition or parafunctional habits,
• patients undergoing radiotherapy or chemotherapy,
• heavy smokers,
• vulnerable groups such as psychologically unstable patients