The Apical Microleakage And Preliminary Clinical Application Of MTA Apical Barriers Technology

Root canal therapy is now the most effective method to cure pulpitis and periapical disease. The root canal obturation which in order to fill the root canal strictly, to prevent microleakage from coronal and root side and avoid re-infection of the root canal system is a key step in the root canal therapy. Therefore, microleakage of the root canal is a important index to evaluate the quality of root canal therapy. When the pulp of immature permanent teeth was damaged irreversibly due to trauma, deformity sharp break and caries whose apical foramen is still immature, perfect root canal filling become difficult. Apical barriers refers to using no operation method to fill the root canal apex with biocompatible material and form an artificial check point in root tip. Research shows that:MTA apical barrier is the effective method to treat pulp necrosis for incomplete teeth. In this study, we use glucose oxidase method to detect MTA, apical microleakage of apical barriers technology, combined with clinical research, a comprehensive assessment of MTA apical barrier surgery in the treatment of the clinical effect of root canal. In this study,we use the Glucose quantitative method to detect the apical microleakage of MTA apical barriers technology. Combined with clinical research, we got a comprehensive assessment of the clinical effect of MTA in the treatment of the root canal.Objective:1.To compare apical sealing ability of the MTA apical barriers with the warm gutta percha and continuous wave technique in vitro.2.To compare the clinical effect of MTA apical barriers technique and traditional apexification in immature permanent teeth with chronic periapical periodontitis,Methods:1.Vitro study:30teeth were randomly divided into the experimental group、the control group and the blank control group (n=10).The length of all the root samples was15.0mm. Use the Protaper nickel titanium system to finish the root canal preparation by Crown-Down technique, all root canal were prepared to the same standard-F3,creating artificial apical foramen(d=0.5mm).The control group were continuous wave hot gutta percha obturation; experiment group were MTA apical sealing and hot gutta percha obturation.The blank control group were filled only with gutta percha, without root canal sealer. After drying,the root tip hole2mm are outside coated with two layers of transparent nail polish; Glucose leakage model is established, in1,4,7,14,21,28days of quantitative method using glucose detection leakage of glucose, evaluation of apical microleakage.2.Clinical study:Forty-four immature permanent teeth with chronic periapical periodontitis which had a closured apex (patient age cann’t exceed16) were selected in the study. In the experimental group, closured apex was strictly sealed with MTA under dental operating microscope and the root canal obturation were finished in one time. In the control group, apexification with Vitapex paste were used and the root canal were filled with thermoplasticized gutta-percha after the formation of apical hard tissue. The patients were recalled in18months, clinical effect and radiographic examination of the teeth were evaluated.Results:1.Vitro study:Comparing with control group,the apical microleakage values of experiment group at every time were lower than control group and the difference was statistically significant.(p<0.01).2.Clinical study:After18mouths, the teeth in the experimental group were asymptomatic, only one apical radiolucent area without improvement in the X-ray film.95.45%teeth were successfully treated. In the control group, one root fracture and four apical barrier wasn’t formed in18months,77.27%teeth were successfully treated. There was statistical difference between two groups about the visits (p<0.01).Conclusions:1. Vitro study:Compared with the continuous wave technique, the MTA apical barriers with the warm gutta percha get the less microleakage.2. Clinical study:MTA is an ideal material for the apical plug which can reduce recall times and treatment period, improve success rate.