2025 Volume 59 Issue 2 Pages 235-253
Obesity is a major risk factor for type 2 diabetes mellitus, and a bidirectional association between type 2 diabetes mellitus and periodontal disease has been established. However, morphological changes in the lingual gingiva of mandibular first molars in an obese type 2 diabetes mellitus environment in rat models remain poorly studied. In this study, we compared obese rat models of type 2 diabetes mellitus with normal rats to investigate morphological differences in the mucosal epithelium, subepithelial connective tissue, and microvascular architecture of the lingual gingiva. The obese type 2 diabetes mellitus group showed significant mucosal epithelial thickening, particularly in the keratinized and granular layers of the upper gingiva, with enhanced desquamability of superficial epithelial cells. Degenerative changes in the subepithelial connective tissue included fine wavy primary ridges and an increased number of secondary ridges. The microvascular architecture revealed significantly smaller capillary diameters and heterogeneous capillary networks. These findings suggest that the obese type 2 diabetes mellitus environment induces abnormal keratinization, enhanced epithelial desquamability, connective tissue degeneration, and vascular remodeling associated with microangiopathy, potentially affecting periodontal tissue homeostasis, as well as providing insights into the mechanisms of periodontal disease progression in diabetes and obesity. (J Osaka Dent Univ 2025; 59: 235-253)
