Alternative TitleEr,Cr:YSGGレーザー照射歯質に対するコンポジットレジンの接着強さ
Note (General)Various types of laser have been developed and put to use in dental procedures in recent years, such as the Er,Cr:YSGG laser, which can be used to cut dental hard tissue. This study focused on 1-bottle 1-step bonding systems, and examined the bond strength of composite resin to the enamel and dentin after irradiation of Er,Cr:YSGG laser, as well as the effects of removing the denatured dentin with clinical tools on the bond strength.As the 1-bottle 1-step bonding systems, we used G-BOND PLUS (GC, GP), and AdperTM EASY BOND (3M, EB). As the test subject teeth, we used bovine teeth whose enamel and dentin surfaces were shaped and abraded to #600 waterproof paper, and laser was irradiated uniformly in a 6mm x 6mm area. We measured the bond strength to the tooth substances in the laser-irradiated group (LI Group) and non-irradiated group (Control Group). To remove the denatured dentin with laser, we also treated the dentin under the following five conditions:・Phosphoric acid etching treatment for 20 seconds after laser irradiation (LI + PA Group)・Cutting with a round bur for 20 seconds after laser irradiation (RB Group)・Cutting with a round bur for 20 seconds after laser irradiation, followed by phosphoric acid etching for 20 seconds (RB + PA Group)・Cutting with a spoon excavator for 20 seconds after laser irradiation (SE Group)・Cutting with a spoon excavator for 20 seconds after laser irradiation, followed by phosphoric acid etching for 20 seconds (SE + PA Group)After the procedure, we measured the bond strength and observed the fracture surface by SEM (n=5). We conducted statistical analysis on the measurement results according to two-way analysis of variance and Tukey’s test (P<0.05). The study was performed after obtaining approval from the Animal Care and Use Committee, Osaka Dental University (Approval No.: 16-09004).As a result of two-way analysis of variance on the effects of Er,Cr:YSGG laser irradiation on the bond strength to enamel and dentin, we found that neither the bonding system nor the use of laser irradiation affected the tensile bond strength to enamel, and observed no interactions between the two factors. However, we found that the bonding system and the use of laser irradiation significantly affected the tensile bond strength to dentin, and observed interactions between the two factors. In addition, the results of Tukey’s test for the experiments on enamel showed no significant difference among the groups. On the other hand, in experiments on dentin, the tensile bond strength was significantly higher in the GP Control Group than the LI Groups for GP and EB, and significantly lower than the EB Control Group. The tensile bond strength of the EB Control Group was significantly higher than in the LI Groups for GP and EB. There was no significant difference in the tensile bond strength between GP and EB, and the two were equivalent. The results of Tukey’s test on the effects of removing the denatured dentin on the bond strength to dentin showed that the tensile bond strength of the RB Group was significantly higher than in the LI, LI + PA, and SE + PA Groups with GP. With EB, the tensile bond strength of the LI + PA Group was significantly higher than in the SE + PA Group. The tensile bond strength of the RB Group was significantly higher than in the LI and SE + PA Groups. The tensile bond strength of the RB + PA Group was significantly higher than in the LI and SE + PA Groups.While the bond strength of the 1-bottle 1-step bonding system to the enamel after Er,Cr:YSGG laser irradiation was favorable in the results of this experiment on the bonding to tooth substances after Er,Cr:YSGG laser irradiation, the bond strength to the dentin turned out to be problematic; further study on the recovery of bond strength is needed. In addition, we found that it was effective to remove the denatured layer from dentin with a round bur after irradiation of Er,Cr:YSGG laser in recovering the bond strength to the resin composite.
2021年度
Collection (particular)国立国会図書館デジタルコレクション > デジタル化資料 > 博士論文
Date Accepted (W3CDTF)2022-06-05T18:01:14+09:00
Data Provider (Database)国立国会図書館 : 国立国会図書館デジタルコレクション