Abstract
Objective: To evaluate the clinical efficacy of chitosan/alginate (CS/Alg) double-network hydrogels in the repair of temporomandibular joint (TMJ) disc defects and to investigate the underlying mechanisms. Methods: A prospective randomized controlled trial was conducted, including 104 patients with irreducible anterior disc displacement or disc perforation of the TMJ who were treated at the Department of Oral and Maxillofacial Surgery between January 2023 and December 2023. Patients were randomly divided into an experimental group (CS/Alg double-network hydrogel implantation, n = 53) and a control group (conventional disc repair or discectomy, n = 51). Randomization was performed using computer-generated random number tables with allocation concealment. Primary outcome measures included maximum interincisal opening (MIO), pain visual analog scale (VAS) scores, and TMJ functional index. Secondary outcome measures included imaging findings, complication rates, and patient satisfaction. Follow-up evaluations were conducted at baseline, 1 months, 3 months, 6 months, and 12 months postoperatively. Results: A total of 96 patients completed the 12-month follow-up (experimental group: 50 patients; control group: 46 patients). No significant differences were observed in baseline characteristics between the two groups (p > 0.05). At 12 months postoperatively, the experimental group demonstrated significantly greater improvement in MIO compared to the control group (13.8± 4.6 mm vs. 7.9 ± 4.3 mm, p < 0.001). The reduction in VAS pain scores was superior in the experimental group compared to the control group (5.4 ± 1.3 vs. 3.8 ± 1.6, p < 0.001). The experimental group achieved higher TMJ functional index scores (82.4 ± 11.2 vs. 71.3 ± 13.6, p < 0.001) and higher treatment success rates (94.0% vs. 78.3%, p = 0.021). Imaging evaluation revealed better preservation of disc position and joint space in the experimental group (p < 0.05). The overall complication rate was significantly lower in the experimental group compared to the control group (20.8% vs. 62.7%, p < 0.001). Multivariable analysis identified CS/Alg double-network hydrogel treatment as an independent protective factor for treatment success (OR = 3.58, 95% CI: 1.42–9.03, p = 0.007). Histological analysis demonstrated good biocompatibility and fibrocartilaginous tissue regeneration. Conclusion: CS/Alg double-network hydrogels exhibit excellent clinical efficacy and safety in TMJ disc repair. Through multiple mechanisms, including providing appropriate mechanical support, modulating the immune microenvironment, and promoting extracellular matrix remodeling, this material significantly improves joint function and patient quality of life, offering a novel and effective therapeutic strategy for TMJ disorders.
Keywords: Temporomandibular joint disc; double-network hydrogel; chitosan; alginate; tissue engineering