Effect of simvastatin administration on periodontitis-associated bone loss in ovariectomized rats

Hydroxyl methylglutaryl-coenzyme A reductase inhibitors, so-called statins, have been widely used for hyperlipidemic patients. Recently, it has been reported that they promote bone formation. The purpose of this study was to evaluate the effect of simvastatin on ligature-induced bone resorption in the mandible of the ovariectomized rat.

Forty-nine rats were divided into seven groups; ligature was placed in all groups except group 7, which was considered the sham group: group 1 (N = 7), ovariectomy (OVX) plus simvastatin (10(-6) M); group 2 (N = 7), OVX plus simvastatin (3 x 10(-7) M); group 3 (N = 7), OVX plus simvastatin (10(-7) M); group 4 (N = 7), OVX plus normal saline; group 5 (N = 7), OVX group; group 6 (N = 7), ligature without OVX; and group 7 (N = 7), sham surgery without OVX and ligature. Simvastatin was administered subperiosteally in the buccal fold of the bottom right first molar twice a week during the study. Four weeks after insertion of the ligatures, the animals were sacrificed. Mandibles were removed for radiologic and histologic analysis. Bone density, bone loss (BL), and attachment loss were measured. Analysis of variance (ANOVA) was used to compare groups.

Histologic analysis showed that the simvastatin groups developed significantly less periodontal breakdown (P <0.05). BL was less in the simvastatin experimental group, but there was not a significant statistical difference between the simvastatin groups (groups 1 through 3) and the experimental control groups (groups 5 and 6; P >0.05).

Within the limits of this study, it can be concluded that simvastatin shows protective features against the impact of periodontitis on attachment apparatus and alveolar bone.