Alternative Title知覚過敏症罹患モデル象牙質を用いたTiO2併用Nd:YAGレーザー照射による象牙細管封鎖性について
Note (General)Purpose: In recent years, there have been reports on the application of Nd: YAG laser (the laser) combined with titanium dioxide (TiO2), a photoreactive agent, to dental treatment, but there have been no reports on its use for dentin hypersensitivity for the purpose of high reactive level laser therapy. In this study, to investigate the transmittance of the laser combined with TiO2 through dentin, the transmitted energy of the laser was measured. Furthermore, to investigate the sealing ability of the laser on dentinal tubules, Nd: YAG laser combined with TiO2 was irradiated to a model dentin affected with hypersensitivity, and the dentin permeability inhibition ratio (permeability inhibition ratio) was measured. Methods: STREAK-1 (ALTECH) was used as the laser system. Human extracted teeth were used as test teeth, and dentin disc specimens of 1.0 mm in thickness were prepared.Experiment 1: Examination of laser penetration through dentinThe irradiation conditions were 50 μs-50 mJ-10 pps, 100 μs-100 mJ-5 pps, and 200 μs-300 mJ-5 pps, and the irradiation time 5 seconds. The laser was irradiated through one to five dentin discs, and the transmittance was calculated. In the same way, the laser was irradiated together with TiO2 solution, and the transmittance was calculated for a single dentin disc.Experiment 2: Examination of dentinal tubule sealing ability of laser combined with TiO2 solutionThe irradiation conditions were 50 μs-50 mJ-50 pps, 100 μs-100 mJ-20 pps, 100 μs-100 mJ-99 pps, and 200 μs-300 mJ-20 pps, and the irradiation time was set to 10 s, 20 s, and 30 s. The specimens were connected to the measuring device and laser was irradiated with TiO2 solution. The permeability inhibition ratio was measured, and the dentin disc surface was observed by SEM. Results: Laser transmittance into dentin significantly decreased with increasing dentin thickness under all the conditions. In addition, the transmittance of the laser significantly decreased under all the conditions when the TiO2 solution was combined. Regarding the sealing ability of the laser combined with TiO2 solution on dentinal tubules, the permeability inhibition ratio increased significantly with increasing irradiation time at 50 μs-50 mJ-50 pps and 100 μs-100 mJ-20 pps. No significant difference was observed in the permeability inhibition ratio at 100 μs-100 mJ-99 pps and 200 μs-300 mJ-20 pps. SEM observation of the surface of the specimens showed that the dentinal tubules were sealed by cohesive structures under all the conditions. Conclusion: The investigation indicates that Irradiation with Nd: YAG laser combined with TiO2, a photoreactive agent, attenuates the penetration of the laser into dentin and it is effective for sealing dentinal tubules.
2022年度
機関リポジトリ記載の権利情報: CC BY-NC-ND
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)2023-05-05T22:12:36+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