| Post-and-core is a petfect restoration method for residual crown or nx~ of pulpless teeth. Mx~ and i~ore emphasis has been placed on how to avoid tooth fiacture and maintain esthetic appearance without reducing strength and retention. Our study is to develop a new type of FRC post and make a serial of study on its clinical application. lii this essay, we reviewed the reseawh status of the composite materials, the nanomaterial and their clinical application .Then we studied the propedies of EAM resin and established the fabricated technology of S-Gf/EAM composite material, and analyzed the effect of nano-scale paiiicles on its pmperties. Primary biocotnpatible evaluation of S-GIYEAM composite niatetial and the development of l~RC post using mould-press were also studied. All of the studies above is to provide theoretical base for clinical application. I. The development of S-GF/EAM composite material in dentistry (I) EAMIBPO systems were studied by gel experiment combined with DSC and infrared- spec~copy analysis, then usage dose of the hardening agent established and the flexural propetlies were tested. It was discovered that the mechanical properties and technical properties of the EAM/BPO system were the best when the content of 13P0 was up to 0.8wt%.( flexuntl strength was 101.84 ?3.30Mpa flexr n-al modulus was 3.08 ?0.11 ).The thermal curve of hardening technology of the system was 901C /30min+ l0(YC/30min+l 3O~Cf30niin. (2) The effects of dime kinds of nano-scale particles on the pwpetlies of EAM resin were studied. The results showed that the properties of the resin 憕vere impcoved, to different extends, with the increase of die content of the nano-scale particles. Different kinds and different contents of the nano-scale particles in the resin could cause different results. The overall properties were the best when the content of Si02 particle was 3wt%. The flexural strength was 126.2SMPa,and the flexural modulus was 3.55Gpa, the impact strength was 15.69KJ/m2, and impmved by 24.0%, 15.3%, 71.7% respectively as compared with these of base material. The maximum of the flexwal strength of die nano-TiOJEAM composite m~ueriai was up to 124.55Mpa (22.3% higher than the base material), the flexwal modulus was up to 3.43Gpa (11.4% higher than the base material), impact strength was 16.361(1/rn2 (79.0% higher than the base material). Nano-A1203 did not dispen~e easily ,so the impact strength of the resin wouldn抰 decrva%c, .7. when the content was 2wt%, the flexural strength was 1 18.23Mpa and the Ilexural modulus was 3.4 lGpa. The ultrasonic combined with high speed dispersion was efficient for the dispemion of nano- particles. (3) We studied the fabricated technology of S-Gf/EAM composite material, mechanical char.~teristic and the conditions of bonding interface. The results were as follows: (DThe forming technique of S-Gf/EAM composite material was: ______ 10mm Room temperature 5~/min 80t, touching pressure O.5MPa force, elevating temperature after 2mm ~C15XLUumfl~~ 9O~ ~ l.5MPa force, elevating temperature atter 20mm it/mm llOt/30min l3Ot/2Omin, holding pressure, cooling to room temperature then open the mould; ~ With the increase of the fibre contents, the flexural strength and il~ modulus of S-Gf/EAM composite material were impnved gmdually; When the fibre content exceeded 8Owt%, the...
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