Morphological changes of dental hard tissues irradiated by Er:YAG laser with different parameters:an in vitro study
YANG Wen-dong
LI Qian
WANG Wei
MA Lin
GUO Chun-lan
ZHANG Xin
GONG Zhuo
ZHAO Ji-zhi
Abstract：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 setting,insufficient water spray or too high pulsing energy can damage the hard tissue.
Keywords：Er:YAG laserscanning electron microscopycavity preparation
Publication Date：2014-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：4( 596-598,585 )