Background: Diabetes, among multiple systemic harmful health issues, also may deteriorate normal regenerative and reparative functions of periodontium. The aim of this research was to study the role of periodontal ligament in tissue remodeling under the orthodontic appliance stimulation in two rat experimental models (healthy Wistar rats and Goto-Kakizaki, rodent model of non-obese type 2 diabetes).

Materials and methods: It was defined four groups of rats: Wistar (n = 8) and Goto-Kakizaki (n = 8) control groups without orthodontic appliances, and Wistar (n = 16) and Goto-Kakizaki (n = 16) appliance groups with orthodontic appliances. After 42 days, rats were sacrificed and histopathology descriptive analysis about periodontal ligament and adjacent structures was performed as well as cellularity of periodontal ligament and Kappa curvature of tooth roots were measured.

Results: Goto-Kakizaki control rats showed statistically significantly higher cellularity in comparison with Wistar control rats (p<0.001). Both applied groups (WI 44.63±6.68; GK 79.58±10.06) also showed statistically significantly higher cellularity (p<0.001) in comparison with control groups (WI 34.48±6.92; GK 45.31±11.18). Applied groups (WI 0.197±0.2; GK 0.126±0.083) had statistically significant higher values of Kappa curvature in comparison with control groups (WI 0.023±0.011; GK 0.037±0.011) (WI appliance vs. WI control p<0.001; GK appliance vs. GK control p<0.05). Agitated periodontal ligament caused different degrees of cementoclasia and additionally dentinoclasia, altering the natural root curvature. In extremely cases, root apex was damaged and dental pulp was altered.

Conclusions: Goto-Kakizaki rats, as diabetes mellitus type 2 animal model, showed constitutional hypercellularity of the periodontal ligament, greater resorptive activity at the level of the molar roots as well as tendency toward prolonged reconstitution of periodontium.