|Title:||Microstructural changes of enamel, dentin-enamel junction, and dentin induced by irradiating outer enamel surfaces with CO2 laser||Authors:||Chiang Y.-C.
|Keywords:||CO2 laser;Dentin-enamel junction;Heat-transfer simulation;Thermal effect||Issue Date:||2008||Journal Volume:||23||Journal Issue:||1||Start page/Pages:||41-48||Source:||Lasers in Medical Science||Abstract:||
The microstructural changes of enamel, dentin-enamel junction (DEJ), and dentin after CO2 laser irradiation were studied. Buccal enamel surfaces of human third molars about 2 mm from the DEJ were irradiated, and the laser tip was moved 5 mm in a mesiodistal direction with 5 s of irradiation time. The output powers were 2 to 10 W in a continuous mode, and the average doses were approximately from 250 to 1,250 J/cm2. All specimens were examined by a scanning electron microscope, and heat-transfer simulation was also applied to calculate temperature distribution. Surface ablation of enamel and separation of enamel and dentin along the DEJ were observed when the laser power output exceeded 3 W. Heat-transfer simulation indicated that dentin was prone to store more thermal energy than enamel. In conclusion, operation parameters of the CO2 laser should be carefully selected to avoid thermal damage to the DEJ. ? 2007 Springer-Verlag London Limited.
|Appears in Collections:||化學工程學系|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.