Effect of Locally-Applied Simvastatin on Clinical Attachment Level and Alveolar Bone in Periodontal Maintenance Patients

The purpose of this study is to determine of local application of commericially-available, FDA-approved preparation of simvastatin is effective in increasing clinical attachment levels (primary outcome), as well as alveolar bone (secondary outcome) compared to standard mechanical therapy in patients on periodontal maintenance therapy (PMT). Subjects undergoing PMT at the UNMC College of Dentistry clinics will be recruited to participate in the randomized one-year clinical trial based on the following eligibility criteria: 1) diagnosis of chronic advanced periodontitis (generalized or localized), 2) participating in regular PMT visits (3-6) month intervals), 3) no systemic diseases or medication which significantly impact periodontal inflammation or bone turnover (e.g. steroids, bisphosphonates, \> 325 mg aspirin/day and in good general health, 4) one experimental quadrant of the mouth with an inflamed 6-9 mm interproximal posterior periodontal pocket with history of bleeding on probing (BOP), 5) willingness to sign consent form. Subjects will be divided into two groups for additional therapy in a 6-9 mm interproximal periodontal pocket at baseline: 1) local anesthesia and mini-flap reflection with subgingival mechanical debridement plus application of the simvastatin-methylcellulose gel or 2) local anesthesia and mini-flap reflection with subgingival mechanical debridement plus application of methylcellulose gel alone. Samples/measurement will be obtained at the designated experimental site at baseline, 2 weeks, 6 and 12 months during PMT: 1) digital radiographs (baseline and 12 months only; bone height measurements), 2) presence of explorer-detectable supragingival plaque, 3) 30-second gingival crevicular fluid (GCF) sample (markers of inflammation, bone turnover), 4) recession from the cemento-enamel junction, 5) probing pocket depth and bleeding on probing (BOP). Following the 12-month visit, the research-specific intervention and measurements in the experiment q