Expressions of osteoprotegerin and receptor activator of nuclear factor Kappa-B ligand in alveolar bone socket under low plasma estrogen level condition

Background: Decreasing of estrogen level can lead to alveolar bone loss. This bone loss reflects an imbalance between resorption and apposition. Receptor Activator of Nuclear Factor Kappa-B Ligand (RANKL) is a key mediator in osteoclast activation, while Osteoprotegerin (OPG) is modulator of bone apposition. Aim and Objectives: To obtain the value of RANKL and OPG expressions in alveolar bone socket under condition of low plasma estrogen level. Materials and Methods: Sixteen female Wistar rats, aged 2-3 months divided into control and treatment group. Ovariectomy was done to treatment group. Seven days after ovariectomy, mandibular right incisor was extracted on each group. Fourteen days after extraction, immunohistochemical examination procedure was performed to determine expressions of RANKL and OPG level in alveolar bone socket. Results: The values of RANKL and OPG expressions in control group respectively were 5.13 ± 0.83 and 14.75 ± 1.39. In the treatment group, the values of RANKL and OPG expressions were 11.63 ± 1.6 and19.88 ± 0.40. Independent t-test showed that there was a significant difference between both groups (p < 0.05). Conclusion: Low plasma estrogen level condition can increase both RANKL and OPG expressions, but the increase was higher in RANKL expressions than in OPG expressions.