Effects of Low-Level Laser Therapy on Histological Changes of Lingual Papillae in Streptozotocin-Induced Diabetes Mellitus in Rats: An Experimental Study
DOI:
https://doi.org/10.15218/edj.2026.6Keywords:
Photo biomodulation Therapy, Hyperglycemia, Tongue, Streptozotocin, Tissue RegenerationAbstract
Background and Objectives: Diabetes mellitus (DM) is associated with structural alterations in oral tissues, including the lingual papillae, where epithelial atrophy, fibrosis, and degeneration of taste buds may occur. Low-level laser therapy (LLLT) has been suggested as a non-invasive therapeutic approach that may enhance tissue repair and regeneration.
Aim: This study evaluated STZ-induced diabetic changes in rat lingual papillae and the therapeutic effect of low-level diode laser therapy.
Methods: 21 Wistar albino rats were used. 3 Rats served as healthy controls, while diabetes was induced in 18 rats by a single intraperitoneal injection of STZ at 50 mg/kg. After confirmation of hyperglycemia (blood glucose level >= 300 mg/dL), diabetic rats were divided into two equal subgroups: untreated diabetic rats and LLLT-treated diabetic rats. Untreated diabetic rats were examined histologically at 2, 3, and 4 weeks after diabetes induction. The treated subgroup received diode laser therapy three times weekly starting 4 weeks after diabetes induction and was evaluated at 6, 7, and 8 weeks. Body weight and blood glucose levels were monitored throughout the study. Tongue specimens were collected for histological and semi-quantitative evaluation.
Results: Untreated diabetic rats showed progressive histological deterioration, including epithelial atrophy, fibrosis, and reduced taste bud density. These changes became more pronounced with longer diabetes duration. In contrast, LLLT-treated rats demonstrated improved epithelial thickness, better preservation of taste buds, and reduced fibrosis.
Conclusion: STZ-induced DM caused progressive degenerative changes in the lingual papillae. LLLT promoted histological improvement and may support tissue repair in diabetic lingual tissues.
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