Evaluated And Compared The Therapeutic Effects Of Different Douching And Disinfecting Drugs In Root Canal Therapy Of Combined Periodontal-endodontic Lesions

Combined periodontal-endodontic lesions occurred in periodontal and endodontic tissue of the tooth. They often appear in late of periodontitis. They are mixed infections with anaerobic bacteria and caused by dental plaque. There are many anatomical approaches between pulp and periodontal tissue, their bacterial toxins and inflammatory products can be penetrated and spreaded in each other, therefore, there are mixed infections induced by periodontal and endodontic pathogens in the root canal system of combined periodontal-endodontic lesions. Especially in combined lesions induced by periodontal infections, the periodontal pathogens often retrograde infects to the root canal through apical foramen, so there are a lot of periodontal pathogens in lower of root canal. Because of the complexity of symptom and pathology, the best choice is the periodontal and endodontic tissue should be treated at the same time. Conventional drugs and methods were still used to treat the pulp disease of combined periodontal-endodontic lesions, but they can not focus on periodontal pathogens in root canal. The structure of the root canal system is complex, the lower root canal often appears some special situations including narrow, winding and many lateral canals, conventional disinfectants and methods of preparation, washing and filling root canal are difficult to remove and kill the mixed infections in root canal and restrain completely their growth. The bacteria and toxins left in root canal system or periodontal tissue maybe the main reason for treatment failure in combined periodontal-endodontic lesions. The same flora infections in periodontal pocket and root canal suggest that the methods of clearing and killing mixed infections induced by pulp and periodontal tissue at the same time are more reasonable. Therefore, in this research the combined periodontal-endodontic lesions were treated under root canal preparation using the crown-down techniques, ultrasonic irrigation and obturation using warm gutta-percha vertical condensation technique. In treatment tinidazole solution was used to wash the root canal and minocycline hydrochloride was used to disinfect the root canal, both antibiotics are all effective for periodontal and endodontic pathogens (especially periodontal pathogens).To compare the therapeutic effect of these drugs and traditional drugs, we can find a reasonable and effective method to treat combined periodontal-endodontic lesions.Objective To compare the therapeutic effects of different root canal irrigants and disinfectants on combined periodontal-endodontic lesions.Methods68teeth of combined periodontal-endodontic lesions induced by periodontal infections were randomly divided into the experimental and control group. In root canal therapy, the experimental group was treated by ultrasonic irrigation with tinidazole solution and disinfection with minocycline hydrochloride, whereas the control group was treated by ultrasonic irrigation with sodium hypochlorite solution and disinfection with calcium hydroxide. All teeth in two groups were treated by root canal preparation using the protaper instruments with crown-down techniques and root canal obturation using warm gutta-percha vertical condensation technique.At the same time of root canal therapy, both groups were treated with systematic periodontal therapy. The plaque index CPLI), bleeding index (BI), probing depth (PD) and clinical attachment level (CAL) were observed at baseline and6weeks、12weeks after periodontal treatments. And treatment efficiency of two groups was evaluated after12weeks.Results1. After six weeks and12weeks, PLI、BI、PD and CAL of both groups had significantly improved compared with the baseline (p<0.01), However, there was no differences about these four indicators between6weeks and12weeks.2. After6weeks, the improvement of four indicators in experimental group were all significantly better than in control group (p<0.05). But after12weeks, only PD and CAL showed significant differences between the two groups (p<0.05).3. After12weeks, the effective power of experiment group and control group was88.24%and73.53%, respectively. The difference between two groups was significant (P<0.05).Conclusion1. Traditional ultrasonic irrigation with sodium hypochlorite solution and disinfection with calcium hydroxide is certain effective in the patients suffered from combined periodontal-endodontic lesions induced by the periodontal infection.2. The short-term therapeutic effect of ultrasonic irrigation with tinidazole solution and disinfection with minocycline hydrochloride were better than traditional ultrasonic irrigation with sodium hypochlorite solution and disinfection with calcium hydroxide.