| With growing application of new technology and materials, the development for the treatment of endodontics has been revolutionizied, more teeth which would be lost in traditional ways can be saved nowadays. As a result, the post and core system to reconstruct endodontically treated tooth become more important. In order to obtain the long-term curative effect of prostheses, choosing an appropriate post and core system is the determining factor. There are some disadvantages associated with conventional metallic posts, such as potential fracture of post or root, difficulties in removing fractured post, disturbance radiographic examination, et al. Therefore, it has been suggested that FRC posts which have a stiffness similar to dentin should be used instead of metallic posts.In 1960s, FRC was firstly used in prosthodontics, and was put into use in many fields soon. Among these usages, the development of FRC post was most successful. Since Duret invented Composipost (RTD, France) in 1988, a variety of FRC posts have been made out, and have been more and more popular in clinic practice.Presently, most commercial available products are straight and parallel-side posts. There is a limit for straight post to reconstructanterior teeth because of disability to adjust angular orientation. Furthermore, most available FRC posts are manufactured by means of thermodynamic fabricated technology, which may cause a number of problems, wasting a great deal energy, pollution of environment as well as difficulties of fabrication in batches. As a result, the products are more expensive than conventional posts. So, more and more scholars and dentists acknowledge that it is necessary to modify forming techniques of FRC post to improve clinical procedure.In this study, a new type of curving FRC post was developed with nano-montmorriolinite, S-GF, EAM and E-51 after screening out the best formulas. The bend angles of new FRC posts were 5°, 10°, 15°. The maximal bend angle of FRC posts and the possibility of clinical applications were determined by investigation the effects of different angles on properties of composite material. To modify forming techniques, a new UV-curing resin (EA) was developed with E-51 and acrylic acid to serve as matrix of FRC post, then a new type of light-curing FRC post was developed and a pilot study was used to estimate the possibility of UV-fabrication technique of FRC post. The whole study is divided into two main parts: the first part is concerning with the development of the new type of curving FRC post, the second part is mainly about the research of possibility of light-curing technique to fabricate FRC post.The main results of this study are as follows:1.EAM and E-51 systems were studied by gel experiment and their mechanical properties were also tested. We found that there were no difference in flexural properties and collision propertiesbetween EAM and E-51. The technical property of EAM (80℃ /60min+90℃/50min+110℃/30min+130℃/20min) was better than that of E-51 (90℃/4h+120℃/3h+180℃/lh). So EAM was chose to serve as resin matrix of FRC post.2.It was found that the mechanical properties of S-GF/EAM composite material were at the best when the content of fiber was 75.2wt%. It' s flexural strength and modulus were 1443.2± 23.3Mpa and 40.2±1.8Gpa.3. Within a definite range, the mechanical properties of FRC materials were improved along with the increase of the content of nano-montmorriolinite. Flexural properties of S-GF/EAM tended to peak when the content of nano-scale particles was 3wt%. Flexural strength was up to 1644.6±21. IMpa, at the same time, flexural modulus was up to 49.6±2.3Gpa.4.Results of TEM suggested that nano-montmorriolinite was dispersed homogeneously in composite, lamination of nano-material could be detected clearly. The above indicated that the means of dispersion of nano-particles were efficient.5.Compared with available foreign FRC posts, curving FRC posts we made had similar mechanical properties, their flexural values could meet the demand of clinical application, but the bend angle should be less than 10°.6.The fabricated technology of light-curing EA system was as follow: 110℃ /110min, the proportion of E-51 and acrylate was 1:0.9mol. Results of infrared- spectroscopy analysis suggested that C=C was detected in new resin, which was an especial aspect in light-curing resin.7.It was discovered that curing speed and mechanical properties were all influenced by the content of light initiator. The...
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