LAUSR

BACKGROUND Periodontal regenerative therapy using bone-substituting materials has gained favorable clinical significance in enhancing osseous regeneration. These materials should be biocompatible, osteogenic, malleable, and biodegradable. This study assessed the periodontal regenerative capacity of a novel biodegradable bioactive hydrogel template of organic-inorganic composite loaded with melatonin. MATERIALS AND METHODS A melatonin-loaded alginate-chitosan/beta-tricalcium phosphate composite hydrogel was successfully prepared and characterized. Thirty-six critical-sized bilateral class II furcation defects were created in six Mongrel dogs, randomly divided and allocated to; sham, unloaded composite, and melatonin-loaded cohorts. Periodontal regenerative capacity was evaluated via histologic and histomorphometric analysis. RESULTS Melatonin-treated group showed accelerated bone formation and advanced maturity, with a significant two-fold increase in newly formed inter-radicular bone compared with the unloaded composite. The short-term regenerative efficacy was evident four weeks postoperatively as a significant increase in cementum length concurrent with reduction of entrapped epithelium. After eight weeks, the scaffold produced a quality of newly synthesized bone similar to normal compact bone, with potent periodontal ligament attachment. CONCLUSIONS Melatonin-loaded hydrogel template accelerated formation and enhanced quality of newly formed bone, allowing complete periodontal regeneration. Furthermore, the scaffold prevented overgrowth and entrapment of epithelial cells in furcation defects.