Effects Of Repeated Infiltrating Firing On The Function Of In-Ceram Alumina Substrate

With the people appreciate the beautiful increasing,the all ceramic dental restorations, including crowns and bridges, are attractive to dentists and patients because they provide better esthetics, low thermal conductive, abrasion resistance, and biocompatibility as compared with traditional porcelain-fused-to-metal restorations. There are many kinds of ceramic materials in domestic and overseas at present. The technologies of making manufacture and the good and bad of materials function are different. Vita In-Ceram Alumina Ceramic has excellent translucent, beautiful outlook and mechanics characteristics. The system has a good future. In case of incomplete infiltration the infiltration process must be repeated. To study the strength, microcosmic and colour change of dirrerent infiltrating firing on Vita In-Ceram Alumina substrate. And also study the fitness of bridge. To explore the relatively stable time.lt can provide experience and basis for clinic. Results are as follows:1.Three-point flexural strength values were 42.78 ± 7.13MPa,195.65± 14.95MPa,352.59 ± 23.28MPa,466.81 ± 24.79MPa,486.71 ± 15.78MPa,458.61 ± 17.78MPa for non-infilration and 1-5 glass infiltration.With the number of times increase,the strength increased between 1 to 3.It is no obviously change between 3 to 5.2.Under scanning electron microscope,the In-Ceram alumina substrate had a noticeable change.The morphology of the alumina particle tend to change into the shape resembling the natural crystal of aluminum,and its size slightly increased.The glass infiltration permeated more sufficient and the deapth more deep with moreinfiltrated.3.The average film thickness at the margin of five groups were considered clinically acceptable.There were no significant differences in the average flim thickness between 1 to 3 groups.After 4 and 5 times,the thickness increased.4.All samples have great changes after infiltrating firing.The repeated infiltrating had increased the number of L* and decreased the number of a* and b*. The totalcolor differences between the third infiltrating and the shade guide is the smallest and in a clinical acceptance.Conclusion: We must considered the suitable number of times of glass infiltration according to the thickness of subtrates.lt is good for the 0.5-lmm thickness crown for infiltrating 1 to 2 and for the 2-3mm thickness bridge for infiltrating 3 times. From it,we can get full of infiltrating,good flexural strength, better esthetics and fitness.