Department of Endodontics, University of Florida, Gainesville, FL 32610-0436, USA.
J Endod. 2010 Apr;36(4):725-8. doi: 10.1016/j.joen.2009.11.017. Epub 2010 Feb 6.
This study compared the reduction of Enterococcus faecalis in straight and curved canals using an erbium, chromium:yttrium-scandium-gallium-garnet laser and irrigation with 6.15% sodium hypochlorite (NaOCl).
Fifty-five single-rooted extracted teeth were divided into straight and curved canal groups. The root lengths were standardized (14.0mm) and NiTi instruments were used to prepare the canals to a size #40/0.06 taper. Irrigation was performed with 6.15% NaOCl and RCPrep (Premier Dental Products Co, Plymouth Meeting, PA) as lubricant. The smear layer was removed with 17% EDTA. The samples were sterilized, inoculated with E. faecalis, and incubated for 48 hours at 37 degrees in a CO(2) chamber. They were then divided into 7 groups: NaOCl in straight canals (NS); NaOCl in curved canals (NC); laser in straight canals (LS); laser in curved canals (LC); positive control straight canals (PCS); positive control curved canals (PCC); and negative control (NegC). Bacterial reduction was measured by counting the colony-forming units (CFUs) and determining the optical density.
Groups NS, NC, and LS exhibited bacterial growth in 1 out of 10 samples (10%). In group LC, three out of 10 samples (30%) showed bacterial growth. Kruskal-Wallis showed a statistically significant difference between all treatment groups and the positive controls (p<0.001). Analysis of variance showed a statistical significant difference in optic density between experimental and positive controls.
Traditional irrigation techniques using 6.15% NaOCl effectively eliminated all bacteria in straight and curved canals. Er,Cr:YSGG laser also effectively removed all bacteria from straight canals. However, in three curved canals, even though there were significant bacterial reductions, they failed to render canals completely free of bacteria.
本研究比较了使用铒铬：钇-钪-石榴石激光和 6.15%次氯酸钠（NaOCl）冲洗液在直形和弯曲根管中减少粪肠球菌的效果。
将 55 颗单根拔出的牙齿分为直形和弯曲根管组。将根长标准化（14.0mm），并使用镍钛器械将根管预备至 #40/0.06 锥度。冲洗液为 6.15% NaOCl 和 RCPrep（Premier Dental Products Co，Plymouth Meeting，PA）作为润滑剂。用 17% EDTA 去除玷污层。将样本进行消毒，接种粪肠球菌，在 37 度 CO(2)培养箱中孵育 48 小时。然后将它们分为 7 组：直根管中的 NaOCl（NS）；弯曲根管中的 NaOCl（NC）；直根管中的激光（LS）；弯曲根管中的激光（LC）；阳性对照直根管（PCS）；阳性对照弯曲根管（PCC）；和阴性对照（NegC）。通过计数菌落形成单位（CFUs）和测定光密度来测量细菌减少量。
NS、NC 和 LS 组各有 1 个样本（10%）显示出细菌生长。LC 组有 3 个样本（30%）显示出细菌生长。Kruskal-Wallis 检验显示所有处理组与阳性对照组之间存在统计学显著差异（p<0.001）。方差分析显示，实验组和阳性对照组之间在光密度上存在统计学显著差异。
使用 6.15% NaOCl 的传统冲洗技术有效地消除了直形和弯曲根管中的所有细菌。Er,Cr:YSGG 激光也有效地从直形根管中去除了所有细菌。然而，在 3 个弯曲根管中，尽管细菌减少了很多，但未能使根管完全无菌。
