Study Of Composite Coralline Paste Used In Treatment Of Perforations Of Pulp Floor And Used As Canal Filling Material

RCT is the most common and effective treatment of pulposis and periapical disease, which removes the stimulator from root canal through preparation, disinfection and fill.It cure pulposis and periapical disease since periapical tissue has the characteristics such as abundant blood supply and strong ability of recovery. The purpose of filling of root canal is to block the channels between root canal or periapical tissue and oral cavity, eliminate secondary infection and prevent the damage to periapical tissue or accelerate the concrescence of injured periapical tissuePerforations of pulp floor is the transfixion of pulp cavity and periodontal tissue caused by improper treatment of dental pulp, pathological absorption or caries. Because periodontal ligament and alveolar below the perforation of pulp floor is injured, the tooth has a pertinacious percuss pain. Some result in the perforation of pulp floor for chronic inflammation and the formation of polypi. In some cases, major deficiency of tooth may give rise to the formation of gumpolypi and hamper chewing. Some cases have to perform a pull-out for unsatisfactory treatment outcome, which cause inconvinience of eating and teeth deformity. It is very necessary to choose proper obturation material.Our experiments studied some functions of CCP by using MTT method, scanning electron microscopy and animal models. Results demonstrated the feasibility of CCP as obturation material in filling root canal and obdurating perforations of pulp floor.1. Study on cytotoxciity of CCP to PDLCs by using MTT method.Cell culture and MTT were used to observe the effect of CCP on PDLCs proliferation. The results showed CCP did not have obvious toxic effects on PDLCs. The study is disparted as follow.2. Ultrastructure of CCP studied by electromicroscopy Electromicroscopical study of ultrastructure revealed poriferousstructure in CCP. The diameter of ultra particles reached lOnm, which showed CCP may be a potent nanometer material3. animal model study of CCPCanine model was prepared manually and divided into groups randomly. CCP, Vitapex and CCP compounded rh-BMP2 were placed in root canal and perforations of pulp floor respectively. Iodoform was administrated in control group. Samples were obtained at different times. Histological observation and analysis were performed. Results showed that there was no remarkable difference in samples of 2 weeks. One-month samples healed better in experimental groups than in control group, while there was no significant difference between different experimental groups. In 3-month samples, CCP group recovered better than Vitapex group, and as well as CCP compoundedrh-BMP2 group. These groups showed better recovery than control group. This shows that CCP may function orientation in tooth cement or cenment-like tissue in periapicai area. Meanwhile the results of perforations of pulp floor were similar to those of periapicai healing, which implies that CCP may be used as an effective material for both root canal filling and obdurate perforations of pulp floor.