特定参数飞秒激光制备离体牙釉质窝洞对髓腔温度的影响  

Influence of intra-pulpal temperature when using femtosecond laser in specific parameters to prepare cavities in tooth enamel: an in vitro study

作　　者：孙玉春[1] Anatoliy Vorobyev 李虹[1] Chunlei Guo 王勇[1] 

机构地区：[1]北京大学口腔医学院·口腔医院口腔医学计算机应用中心,口腔数字化医疗技术和材料国家工程实验室,北京100081 [2]The Institute of Optics, University of Rochester, Rochester, New York 14627, USA

出　　处：《北京大学学报（医学版）》2013年第2期286-290,共5页Journal of Peking University:Health Sciences

基　　金：“十二五”国家科技支撑计划项目(2012BA107B00);北京市科技新星计划项目(2008A009)~~

摘　　要：目的:用特定参数飞秒激光在离体牙釉质层制备窝洞,实时监测髓腔温度(intrapulpal temperature,IPT)变化,并初步评价风冷的效果。方法:人类离体牙(前磨牙、磨牙)截根,暴露髓腔。髓腔内填入铜粉,将热电偶置于髓腔中央,将铜粉压实。用绝热胶带封闭髓室底部。室温下,用飞秒激光在离体牙颊面釉质层逐行扫描切削,以0.4 mm/s的平均速度制备边长为2.25 mm的正方形窝洞,用热电偶电子测温仪实时监测髓腔温度变化,温度升至平稳状态后加入风冷。结果:髓腔温度升高量为ΔT,前磨牙风冷前最大ΔT=12.3℃,风冷后温度下降,ΔT=3.0℃。磨牙风冷前最大ΔT=1.8℃,风冷后ΔT=-0.1℃。结论:用特定参数飞秒激光在离体牙齿釉质表面制备平均深度约为250μm窝洞时,牙髓腔温度会随着切削深度的增加而升高,风冷可有效控制温度升高程度。Objective： To take the real-time measurement of the intra-pulpal temperature （IPT） when using femtosecond laser in specific parameters to prepare cavities in tooth enamel in vitro, and to prelimi-narily evaluate the effect of air cooling. Methods： All pulp champers of extracted human teeth （ premolars and molars） were exposed by roots amputated and pulp scraped out. All chambers were tightly filled with copper powder, and thermocouple was inserted into the center of the powder stack. The bottom of the chamber was sealed with insulating tape. Thermocouple wire was fixed at the same time. The 2.25 mm x 2.25 mm square cavities were prepared using femtosecond laser in the enamel with the average scan speed of 0.4 mm/s. The real-time IPT change was measured with thermocouple digital thermometer. Air cooling was added to the procedure once the temperature increased to reach a balance. Results： The IPT rising was defined as AT . Before the usage of air cooling, the maximum of the AT value of the sample premolar was 12.3 ℃ . After using air cooling, the IPT decreased and △T value became 3.0 ℃ . The maximum of △T of the sample molar before using air cooling was 1.8 ℃ , and decreased to - 0.1 ℃ af-ter it. Conclusion： When preparing a cavity whose average depth is about 250 μm by femtosecond laser system in specific parameters, the IPT rises while the depth increass, but it could be controlled effective-ly by air cooling.

关 键 词：牙窝洞制备 牙髓腔 温度 飞秒激光 牙釉质 

分 类 号：R781.05[医药卫生—口腔医学]