| Periodontal disease was one of prevalence and liability oral diseases. Gingivitis and periodontitis were chiefly two kinds of periodontal diseases. Periodontal disease was a group of ailments that occurred in periodontal tissue. Its results were junction epithelium migration to the dental root, periodontal pocket formation, tooth mobility or displace. Serious Periodontal diseases can cause loss of tooth. Now, in the word, there isn't better method on treating the diseases.Bacteria infection, especially the anaerobic bacteria, was the initiating factor of periodontal diseases, so how to efficiently control the infection was the mainly objective of treatment and prevention periodontal diseases in clinic. At present, there are two methods to eliminate or decrease pathogenic bacteria. One is to remove all the dental plaque and calculus adhered to the teeth surface by using mechanical tools in order to decrease the amount of bacteria around teeth. However, the working rationale and character are different from all ultrasonic scaler and their effect and advantages or disadvantages are seldom compared and estimated in our country by special clinical research. These results will bring some difficulties on the selection of different scaler for clinical use. The other is to control the periodontal anaerobic bacteria by using drugs such as metronidazole and tinidazole, the most widely used drugs particularly anti-anaerobic bacteria drugs. Because oral application drugs must be used higher dosage, it may bring some side effects such as nausea, liver damage, anorectic reaction, etc. Local drugs can also overcome these shortcomings,so local sustained-delivery drugs will be widely applied. It have become great focus in the recent research.Chitosan, the disacetylizad derivative of chitin, was the only alkaline polysaccharide in nature. Special chemical structure brought it interesting bioactivities, such as antimicrobial, anti-tumor, immune enhancing effect and tissue regenerative activities. It was widely used in medical field due to its additional biocompatibilily and biodegradability. Chitosan could be easily made various dosage form to be applied in various drug delivery pathways. In addition, its special bio-adhesive property help to prevent the rapid elimination caused by the flushing action of saliva. As an important derivative of Chitosan, Silver Carboxymethyl Chitosan (CMCT-Ag+) owned sterilizing ability besides of the characteristic bioactivities and biocompatibility of Chitosan. It was an ideal sustained-delivery drug. CMCT-Ag+ had great application potential in preventing and treating periodontal.In this study, we synthesized CMCT-Ag+ by alkalization, modification of chloracetic acid and ion exchange. Then, we observed the effect of CMCT-Ag+ against Porphyromonas gingivalis(Pg) by the agar diffusion and plate serial dilution test. We set up periodontitis model in rats. Then, the CMCT-Ag+ therapeutic effects to periodontitis rats were detected by the PLI, BI and ABL. The results indicated that CMCT-Ag+ was pink powder, and the content of Ag+ was 10.21 % in the obtained CMCT-Ag+. The inhibitory concentration of CMCT-Ag+ ranged from 0.31 mg/ml to 40 mg/ml, and the minimal inhibitory concentration (MIC) was 1.25 mg/ml. In the CMCT-Ag+ group, PLI and BI were significantly improved compared with the Periodontitis group (P<0.05). But the repair of alveolar bone loss was not obviously. By pathological observation, we discovered that Periodontitis group had some changes of inflammatory cell infiltration, alveolar bone loss and periodontal pocket formation. In CMCT-Ag+ group, inflammatory cell infiltration was obviously release, periodontal pocket transformed superficial and dento-soft tissue was obviously repaired, but alveolar bone loss still exist. These results showed that CMCT-Ag+ could significantly treat rats periodontitis, but the destruction of alveolar bone was not recovered in short time. Our results showed that the CMCT-Ag+ could inhibit the growth of Pg, treat rats periodontitis by inhibition periodontal bacteria. This study provided theoretical and experimental foundation for prepaing local drug of sustained-delivery systems and developing higher efficiency and reducing side-effect drug to treat periodontal disease. |