Özet:

Purpose: The aim of this study is to study the effect of the application of the 32% hydrogen peroxide tooth whitening agent activated by LED light on the lithium disilicate veneers after adjective resin symtation in different periods. Instrument and method: Thirty-five pieces are drawn, the upper center is divided into three groups of female humans (n=15). The control group (K) is designed to be whiteed without the process of application of the teeth are prepared at the mine level, and the lithium disilicate veneers are simulated. Examples in the whitening groups were activated with LED light on the labial surfaces, and a 32% hydrogen peroxide agent was applied. Immediately after the process of whitening (Group B0), the tooth mine level was prepared and simulations were made. Examples from the other whitening group (Group B7) were stored in 370C distillated water for 7 days after the process of whitening, preparation and simulation were made. After simulation, each group is kept 24 hours in 370C distilled water and the samples' scattering connectivity resistance is measured at a progress rate of 0.5 mm per minute in the universal test device. The breaking patterns of the tooth and ceramic samples have been studied under a light microscope. For the comparison of normal distribution data, one-way variance analysis (ANOVA) was used, while Bonferroni corrected average comparison was made to find out where the difference between the groups originated. Results: The K-Group's average scattering connection resistance values were 30,04 MPa, while the B-Group's average scattering connection resistance values fell to 20,34 MPa, and the B7-Group's average scattering connection resistance values rose to 27,02 MPa. The connectivity of the tooth that was restored immediately after whitening was significantly reduced (p<0,001). In the K group, type 1 and type 3 breaking patterns were observed, while type 2 breaking patterns were not observed. The B0 group contains type 2 and type 3 breaking patterns, but type 1 breaking patterns are not seen. In the B7 group, all the broken fathers were seen. The result: Application of restoration to the teeth after the process of whitening negatively affects the connection of the resin to the mine. If the full ceramic restoration is planned to apply the LED-activated whitening process to the teeth, it is recommended to wait at least 1 week after the whitening process.  Keywords: LED, hydrogen peroxide, resin siman, grinding connectivity. THE EFFECT OF TOOTH BLEACHING ON THE BOND STRENGTH OF A LITHIUM DISILICATE CERAMIC ABSTRACT Aim: The aim of this study was to investigate the effect of 32% hydrogen peroxide bleaching agent activated by LED on the shear bond strength of lithium disilicate veneers after adhesive resin cementation. Materials and Methods: Forty-five extracted human maxillary central teeth were divided into 3 groups (n = 15). The control group (K) was designed as without bleaching and the teeth were prepared at the emal surfaces and lithium disilicate veneers were cemented with adhesive resin cement. The other groups, 32% hydrogen peroxide agent activated by LED was applied to the labial surfaces of teeth. Following the bleaching immediately, tooth reduction was made on emal surfaces and cemented with adhesive resin cement (Group B0). The samples of the other bleaching group (Group B7) were stored in 370C distilled water for 7 days after bleaching then, tooth reduction was made on emal surfaces and cemented with adhesive resin cement. After cementation, each group was kept in 370C distilled water for 24 hours and the shear bond strength values were measured by a universal testing machine with a crosshead speed of 0.5 mm/min. The failure modes of tooth and ceramic samples were examined under light microscope. One way ANOVA test was used in comparison of groups and Posthoc Bonferroni multiple comparison test was used to specify the differences. Results: The mean shear bond strength values of the K group were 30.04 MPa, while in B0 group decreased to 20.34 MPa and in B7 groups increased to 27.02 MPa. Immediately after bleaching, the shear bond strength values of the teeth were significantly reduced (p <0.001). While type 1 and type 3 failure modes were observed in group K, type 2 was not observed. While type 2 and type 3 failure modes were found in group B0, type 1 failure mode was not observed. All failure modes were observed in group B7. Conclusion: Adhesive restoration of the teeth after bleaching negatively affects the bonding of resin to the emal. It is recommended to wait for at least 1 week after bleaching activated by LED, if it is planned to make an all-ceramic restoration.  Keywords: LED, hydrogen peroxide, resin cement, shear bond strength.

Anahtar Kelimeler: