Fegan S E, Steiman H R
Department of Endodontics, University of Detroit-Mercy School of Dentistry, Michigan 48093, USA.
J Endod. 1995 Aug;21(8):415-7. doi: 10.1016/S0099-2399(06)80827-7.
The purpose of this study was to determine if the Nd:YAG laser was capable of disinfecting contaminated root canals in vitro. Eighty canals of extracted single-rooted teeth were prepared to size 35 K-file. The teeth were sterilized with ethylene oxide gas and then inoculated with Bacillus stearothermophilus. Eight groups were treated as follows: 1, sterility control; 2, positive control, no treatment; 3, hand instrumentation with sterile water filling chamber; 4, hand instrumentation with NaOCl (5.25%) filling chamber; 5, ultrasonic instrumentation with sterile water; 6, ultrasonic instrumentation with NaOCl; 7, laser exposure with sterile water; and 8, laser exposure with NaOCI. All instrumentation times were 1 min. Teeth were then flushed with 1.0 ml of sterile water onto blood agar plates, and the number of colony forming units were determined. Results indicate that: (i) all groups treated with NaOCI effectively inhibited the growth of B. stearothermophilus; (ii) hand and ultrasonic instrumentation with sterile water did not effectively disinfect root canals; and (iii) the Nd:YAG laser was effective in inhibiting the growth of B. stearothermophilus. The effects of the Nd:YAG laser on other bacteria more commonly found in root canal systems should be evaluated.
本研究的目的是确定钕钇铝石榴石（Nd:YAG）激光在体外是否能够对受污染的根管进行消毒。将80颗拔除的单根牙的根管预备至35号K锉。牙齿用环氧乙烷气体灭菌，然后接种嗜热脂肪芽孢杆菌。八组的处理如下：1，无菌对照组；2，阳性对照组，不处理；3，用无菌水冲洗根管的手用器械预备；4，用5.25%次氯酸钠冲洗根管的手用器械预备；5，用无菌水冲洗根管的超声器械预备；6，用次氯酸钠冲洗根管的超声器械预备；7，用无菌水冲洗根管的激光照射；8，用次氯酸钠冲洗根管的激光照射。所有器械预备时间均为1分钟。然后将牙齿用1.0 ml无菌水冲洗至血琼脂平板上，测定菌落形成单位的数量。结果表明：（i）所有用次氯酸钠处理的组均有效抑制了嗜热脂肪芽孢杆菌的生长；（ii）用无菌水进行的手用和超声器械预备未能有效消毒根管；（iii）Nd:YAG激光可有效抑制嗜热脂肪芽孢杆菌的生长。应评估Nd:YAG激光对根管系统中更常见的其他细菌的作用。
