| Since Brecker introduced metal-porcelain restoring technique in the field of dental restoration in 1956, its theoretical system has gradually become sophisticated and it has been widely applied clinically. However, there are still many unsatisfactory shortcomings, especially the complexity of its preparation technique which hinders its further development. To solve this difficult technique problem, the American Captek Company has developed a new metal-porcelain restoring technique-Captek restoring technique in recent years. The features of this technique are : preparation of metal basis is directly completed by fusing in porcelain baker without wax pattern preparation, embedding and casting; preparation in technique room is simple and it has advantages of traditional porcelain fused to metal, such as good biological compatibility, erosion resistance and so on. So some scholars believe Captek restoring technique is a great progress in metal-porcelain restoring technique. However, at present study on clinic application of Captek prosthesis is rarely reported. The aim of this paper is to study color and marginal adaptability of Captek prosthesis and combination of basis and porcelain interface by color measuring instrument, 6-point measuring instrument of prosthesis adaptability and metal-porcelain interface analysis ofelectronic probe. We can get the results as follows:1. Experimental study of effect of Captek basis on color of baked porcelain prosthesisThree basis alloys-Captek, Pentron Bio86 and Ni-Cr and two kinds ofporcelain power - Ivoclar and Ceramco were selected to make 6experimental groups of åº7mmx0.5mm Captek/Ivoclar, Captek/Ceramco,Pentron Bio86/Ivoclar, Pentron Bio86/Ceramco, Ni-Cr/Ceramco andNi-Cr/Ivoclar and 2 control groups of two kinds of porcelain powerwithout basis respectively. CLE1976 L*a*b color degree system was usedto measure value of L*a*b of each sample with Minolta [CR-22]colorimeter. Results: When Ivoclar used, a* value of Ni-Cr group washigher than that of-Captek group and Pentron Bio86 group (P<0.05),which indicated the color of subject was redder; L* value and b* value of3 experimental groups had no great difference (P>0.05); color differencesamong 3 experimental groups were less than 1.5; color differences amongCaptek group, Pentron Bio86 group and control group without basis wereless than 1.5 without gross difference; color difference between Ni-Crgroup and control group was more than 1.5 with gross difference. WhenCeramco porcelain power used, there was no statistic difference in L*a*bvalue among 3 experimental groups (P>0.05); color difference betweenCaptek/Pentron Bio86 was less than 1.5, while difference betweenCaptek/Ni-Cr and difference between Ni-Cr/ Pentron Bio86 were bothmore than 1.5; color differences between Captek group, Pentron Bio86group and control group were both less than 1.5 without gross difference,while color difference between Ni-Cr group and control group was morethan 1.5 with gross difference.2. Adaptability study of Captek basis crownCaptek (experimental group), Pentron Bio86 (control group 1) and"Ni-Cr (control group 2) were selected to make baked porcelain basis crown according to the fabricated model size. By 6-point measuring method (Aland A2 at the edge of tooth-linked surface, Bland B2 in the middle of axial surface, Cland C2 on the shoulder), gap between basis crown tissue surface and die was measured.The results showed that the mean value of experimental group at Al, A2, Bl, B2, Cland C2 was 65.00 6.62, 71.50 6.64, 24.52 4.14, 25.93 3.33, 85.16 5.84 and 98.02 4.10 respectively; P value of experimental group and control group 2 at Al, A2, Bl, B2, Cland C2 was 0.781, 0.909, 0.258, 0.576, 0.398 and 0.734 respectively, which indicated no statistic difference at 6 points (P>0.05); P value of experimental group and control group 1 at Al, A2, Bl, B2, Cland C2 was 0.018, 0.037, 0.172, 0.568, 0.006 and 0.008 respectively, of which there were sta... |
