Abstract: Objective: To explore impacts of high-fat diet on stability of silk ligature in combined obesity and ligation-induced periodontitis mouse models. Methods: One hundred and thirty-four mice were divided into high-fat (HFD, n = 77) and low-fat diet (LFD, n = 57) groups to induce obesity and normal-weight control, respectively. After 8, 16 or 30 weeks on diet, all mice were induced periodontitis with silk by one-time ligation for 5 or 10 days. Effects of diet type, duration on diet and ligation duration on ligature detachment were statistically analyzed. Results: The total detachment rate of ligature was 5.97%. The 10-day group had 2 times higher (8.04% vs. 2.50%, P < 0.01) and the HFD group had 4 times higher (9.09% vs. 1.75%, P < 0.05) detachment rates compared with those of 5-day and LFD groups, respectively. Duration on diet had no significant effect on detachment rate. Conclusion: When establishing combined models of diet-induced obesity and ligation-induced periodontitis, high-fat soft diet significantly increases detachment of silk ligature. To reconcile the contradiction between protecting obese condition and increased ligature detachment due to overtime ligation, 10 days’ ligation is an appropriate threshold to stop induction or to change silk ligature.

Key words: Obesity, Periodontal diseases, Models, animal, Silk, Ligation, Detachment, Diet