Reabsorção óssea alveolar na periodontite induzida por ligaduras com fios de algodão e de seda em camundongos fêmeas

Abstract

The ligature-induced periodontitis model in mice has been widely used to study bone metabolism, particularly to evaluate bone resorption resulting from an inflammatory process, and is effective for studying alveolar bone resorption (ABR). This study aimed to compare inflammatory levels at different euthanasia times using cotton and silk threads for inducing periodontitis in the mandibles of female mice. A total of 78 female Swiss mice were used, with approval from the Ethics Committee on Animal Use (06/23). Periodontitis was induced by the insertion of silk or cotton threads into the mandibular first molars, with euthanasia performed after 3, 5, 7, 11, 14, and 21 days. A control (Naïve) group, without induced disease, was included for comparison. ABR was assessed by macroscopic analysis, and gingival tissue was collected for quantification of TNF-α and IL-1β via ELISA. Blood samples were also collected to measure serum alkaline phosphatase levels. The animals' weight was recorded before ligature placement and before euthanasia. Both the cotton and silk groups showed significant ABR (p<0.05) starting from day 3, with a peak on day 14, compared to the Naïve group, stabilizing on day 21. The comparison between groups revealed more pronounced ABR (p<0.05) on days 7 and 11 in the silk group. Regarding TNF-α levels, no significant differences were observed compared to the Naïve group. However, IL-1β levels significantly increased (p<0.05) on days 3 and 5 in both groups, indicating an increase in this cytokine at the early stage of the inflammatory process. For alkaline phosphatase, significant differences (p<0.05) were observed in the cotton group on days 7, 11, 14, and 21, while in the silk group, this difference occurred only on day 11. No significant changes in body weight were observed in the periodontitis animals compared to the Naïve group. It can be concluded that ABR occurs in both groups, but it is established more rapidly with the use of cotton threads.