ABSTRACT
<p><b>OBJECTIVE</b>To observe the effect of the self-made chitosan thermosensitive hydrogel system with dual-release bone morphogenetic protein and chlorhexidine on periodontal defects repair.</p><p><b>METHODS</b>The furcation defect model was established on dog premolar. The models were divided into five groups, including three experimental groups, one control group and one blank control group. The hydrogel with the chlorhexidine/3-cyclodextrin inclusion complexes (IC) /rhBMP-2, hydrogel with rhBMP-2, hydrogel with IC, the pure hydrogel were applied to the defects of the four groups, respectively, and the blank control group did not receive any agent. The dogs were sacrificed 8 weeks later and the periodontal regeneration and gingival condition were observed by histological examination.</p><p><b>RESULTS</b>Obvious periodontal tissue regeneration was found in group one and two. The heights of new bone reached 99.2% of the defects in group one, 87.8%, 63.6%, 37.0% and 34.3% in group two, three, four and blank control groups, respectively. The inflammation of the affected gingiva showed less significant in group one and group three than in the other groups.</p><p><b>CONCLUSIONS</b>rhBMP-2 and chlorhexidine played their independent role in repairing periodontal defects and the dual-release chitosan thermosensitive hydrogel system is effective and convenient to use.</p>