Long-term evaluation of oral gavage with periodontopathogens or ligature induction of experimental periodontal disease in mice

To evaluate in long-term periods the destruction of periodontal tissues and bacterial colonization induced by oral gavage with periodontopathogens or ligature experimental periodontal disease models. Forty-eight C57BL/6 J mice were divided into four groups: group C: negative control; group L: ligature; group G-Pg: oral gavage with Porphyromonas gingivalis; and group G-PgFn: oral gavage with Porphyromonas gingivalis associated with Fusobacterium nucleatum. Mice were infected by oral gavage five times in 2-day intervals. After 45 and 60 days, animals were sacrificed and the immune-inflammatory response in the periodontal tissue was assessed by stereometric analysis. The alveolar bone loss was evaluated by live microcomputed tomography and histometric analysis. qPCR was used to confirm the bacterial colonization in all the groups. Data were analyzed using the Kruskal-Wallis, Wilcoxon, and ANOVA tests, at 5 % of significance level. Ligature model induced inflammation and bone resorption characterized by increased number of inflammatory cells and decreased number of fibroblasts, followed by advanced alveolar bone loss at 45 and 60 days (p