Study On Color Stability And Adhesive Properties Of CAD/CAM Integrated Fiber Post And Core After Dyeing

ObjectiveIndividualized aesthetic restoration of teeth is becoming more and more popular among medical staff and patients.With the clinical application of CAD/CAM integrated fiber post and core,by simulating the color of discolored dentin,the CAD/CAM integrated fiber post and core are dyed.Cast porcelain full crown restoration provides another choice for personalized dental restoration.However,there is no research report on the long-term stability of the color after dyeing and the bonding performance after dyeing.Therefore,this experiment intends to conduct related research on whether the color stability and bonding performance of the CAD/CAM integrated fiber post and core dyed has an effect,and simulates the color change of the CAD/CAM integrated fiber post core dyeing in the clinical personalized aesthetic repair work the clinical effect of dentin color provides experimental evidence.MethodsAccording to the design requirements,a total of 20 specimens of CAD/CAM integrated fiber post and core were cut and divided into a control group(n=10)and a dyeing group(n=10),and then the two groups of specimens were respectively repaired with cast porcelain crowns.The CIE-1976L~*a~*b~*color system recommended by the International Commission of Illumination was used to determine the 7d,15 d,30d,60 d,90d and subsequent days after the CAD/CAM integrated fiber post and core dyeing and artificial saliva soaking with the Crystaleye spectrophotometer.The L~*,a~*,b~*values of 1/3 of the labial side of the cast porcelain crown after 1d,7d,and 13 d of UV irradiation.According to the formula △E=[(△L~*)2+(△a~*)2+(△b~*)2]1/2,calculate the color difference before and after aging(△ E),and then compare with the color difference threshold.The universal material testing machine uses tensile test to detect the bonding performance of the two groups of specimens,and uses SPSS23.0 software for statistical analysis.ResultsThere was no statistical difference in the L~*,a~*and b~* values on the surface of the cast porcelain specimens before and after artificial accelerated aging between the two groups of specimens(P>0.05).With the extension of the aging time,the L~* value of the two groups of test pieces is gradually reduced,the a~*,b~* value and △ E value gradually increase,the lightness gradually decreases,and the color has a tendency to become red and yellow.The difference gradually increases.On the 13 th day of UV light aging,the color difference from the baseline value was the largest,which was 2.05±0.68 in the control group and 2.14±0.73 in the dyeing group.The color difference value before and after aging is △E<3.3,which is within the clinically acceptable range;the adhesive force of the control group is(513.78±57.69)N,and the adhesive force of the staining group is(486.09±70.10)N.There was no statistical difference between the two groups in the maximum adhesion force(P>0.05).ConclusionsThe experimental results show that the dyed CAD/CAM integrated fiber post nuclear power can effectively simulate the color of discolored dentin.Under the condition of artificial accelerated aging,it has good color stability,good bonding performance,and the adhesive force is in line with the range of clinical application.