Testosterone is the main male sexual hormone and its concentration may present great variation induced by physiological, pathological or pharmacological mechanisms. Since its role on the periodontium and on inflammation in general has not been established, the purpose of this study was to assess the consequences of supra and subphysiologic levels of testosterone on ligature-induced bone loss in rats, and to evaluate if models of acute (4 days) or chronic (30 days) testosterone depletion or injection would affect the results. Three rats were used to observe the course of serum testosterone concentration following orchiectomy and testosterone injection. Other twelve rats were randomly assigned to one of the following groups: 1) control; 2) ligature-control, receiving ligatures in both lower first molars; 3) orchiectomy (OCX) and ligature 4 days later; 4) OCX, weekly injections of testosterone (T) and ligature 4 days after OCX; 5) OCX and ligature 30 days later; 6) OCX, T and ligature 30 days after OCX. Fifteen days after ligature placement the rats were killed and their hemi-mandibles were used for radiographic and histometric analyses. The results demonstrated that bone loss was similar for ligature-control and test groups, but group tests presented increased gingival area, independently from orchiectomy time period. Within the limits of this pilot study, it is suggested that supra and subphysiologic levels of testosterone do not influence ligature-induced bone loss but present a regulation effect on gingival volume. Additionally, acute and chronic models of testosterone depletion did not significantly alter the results.