Osteoporosis and periodontal disease are linked by an altered receptor activator of nuclear factor B-K ligand and osteoprotegerin ratio (RANKL/OPG), and medical treatment with bisphosphonate (BP) may help control these molecules. The effect of BP on clinical findings and gingival crevicular fluid (GCF) values of RANKL and OPG using enzyme-linked immunosorbent assays was evaluated in postmenopausal women; 13 patients with both chronic periodontitis and osteoporosis (group A), 12 systemically healthy patients with chronic periodontitis (group B), 12 periodontally healthy patients with osteoporosis (group C), and 10 systemically and periodontally healthy individuals (group D). Recordings were repeated at the end of months 1, 6, and 12 in groups A, B, and C. At the baseline, groups A and B exhibited the lowest OPG values (P0.008). The use of BP may be effective in preventing periodontal breakdown by controlling the levels of these markers in osteoporosis as an adjunct to periodontal treatment.