CAJ | 학술논문

目的：观察Er：YAG激光对离体人牙进行窝洞预备后的形态学改变，比较不同的能量设置及不同的水气比作用下的预备效果。方法：将10个无龋的离体磨牙随机分为5组（n＝2），分别用不同Er：YAG激光参数进行窝洞预备。扫描电镜下观察牙釉质和牙本质的形态学改变。结果：经Er：YAG激光照射后，牙釉质呈现出一个粗糙不平的表面，牙本质层清洁，小管开放。在总功率相近的情况下，当水冷却降到50％或切割牙釉质时脉冲能量增加到700 mJ、切割牙本质时脉冲能量增加到400 mJ时，牙釉质及牙本质表面可发生部分熔融改变。结论：Er：YAG激光使用合适的参数进行牙体硬组织的切割安全有效，但在功率相近的情况下，水冷却不足或能量过大（牙釉质＞700 mJ，牙本质＞400 mJ）可损伤牙体组织。
목적：관찰Er：YAG격광대리체인아진행와동예비후적형태학개변，비교불동적능량설치급불동적수기비작용하적예비효과。방법：장10개무우적리체마아수궤분위5조（n＝2），분별용불동Er：YAG격광삼수진행와동예비。소묘전경하관찰아유질화아본질적형태학개변。결과：경Er：YAG격광조사후，아유질정현출일개조조불평적표면，아본질층청길，소관개방。재총공솔상근적정황하，당수냉각강도50％혹절할아유질시맥충능량증가도700 mJ、절할아본질시맥충능량증가도400 mJ시，아유질급아본질표면가발생부분용융개변。결론：Er：YAG격광사용합괄적삼수진행아체경조직적절할안전유효，단재공솔상근적정황하，수냉각불족혹능량과대（아유질＞700 mJ，아본질＞400 mJ）가손상아체조직。
AIM To observe the morphological changes of dental hard tissues irradiated by Er:YAG laserwith different parameters .METHODS:10 extracted caries-free human molars were randomly divided into 5 groups(n =2)and were prapred by Er:YAG laser with 200 mJ/40 Hz/8 W/100%water for enamel and 100mJ/40Hz/4W/100%water for dentin(group 1).400 mJ/20 Hz/8 W/100%water for enamel and 200 mJ/20 Hz/4W/100%water fordentin(group 2).400 mJ/20 Hz/8 W/50%water for enamel and 200 mJ/20 Hz/4 W/50%water for dentin(group3).400 mJ/20 Hz/8 W/100% water for enamel and 300 mJ/15 Hz/4.5 W/100% water for dentin (group4 ).700 mJ/10 Hz/7W/100%water for enamel and 400 mJ/10 Hz/4 W/100% water for dentin(group 5),respectively.After preparation,the samples were observed under SEM.RESULTS:The enamel showed a clear rough surface aftertreatment,the dentin showed open dentinal tubules and no smear layer.But when water spray decreased to 50% or thepulse energy increased to 700 mJ for enamel and 400 mJ for dentin,melting areas were detected.CONCLUSION:Appropriate parameters of Er:YAG laser is safe and effective for dental hard tissue ablation.Under the same power setting,insufficient water spray or too high pulsing energy can damage the hard tissue.