Department of Endodontics, Faculty of Dentistry, Estácio de Sá University, Rio de Janeiro, RJ, Brazil.
Int Endod J. 2012 Sep;45(9):871-7. doi: 10.1111/j.1365-2591.2012.02045.x. Epub 2012 Mar 27.
Bacterial reduction in oval-shaped root canals by a single-instrument technique was compared ex vivo with a conventional nickel-titanium rotary technique. Data obtained from two quantification methods, quantitative real-time polymerase chain reaction (qPCR) and culture, were also compared.
Oval-shaped canals of extracted teeth contaminated with Enterococcus faecalis were instrumented using either a single Reciproc instrument or the BioRaCe instrument series. Bacteriological samples were taken before (S1) and after instrumentation (S2). Bacterial quantification was performed using qPCR and culture.
Intragroup analysis showed that both protocols promoted a highly significant bacterial reduction (P < 0.001). Intergroup analysis (S2 samples) showed no significant differences between the two instrumentation systems (P > 0.05). As for the quantification methods, qPCR revealed significantly higher counts of E. faecalis in S1 than culture (P < 0.05), but no significant differences occurred for S2 (P > 0.05).
The single-file technique was comparable with the conventional technique in oval-shaped canals provided the width of apical preparation, volume of irrigants and duration of irrigation are kept similar. No significant difference was observed for qPCR and culture in post-instrumentation samples, indicating that both methods can be reliably used for studies of antibacterial effectiveness.
比较单器械技术和传统镍钛旋转技术在椭圆形根管中对细菌的减少效果。还比较了两种定量方法，即实时定量聚合酶链反应（qPCR）和培养法所获得的数据。
使用 Reciproc 或 BioRaCe 器械系列对含有粪肠球菌的椭圆形根管进行器械处理。在器械处理前（S1）和后（S2）采集细菌样本。使用 qPCR 和培养法进行细菌定量。
组内分析显示，两种方案均能显著减少细菌（P<0.001）。组间分析（S2 样本）显示两种器械系统之间无显著差异（P>0.05）。对于定量方法，qPCR 在 S1 时显示粪肠球菌的计数明显高于培养法（P<0.05），但在 S2 时无显著差异（P>0.05）。
在保持根尖预备宽度、冲洗液体积和冲洗时间相似的情况下，单器械技术在椭圆形根管中与传统技术相当。器械处理后样本的 qPCR 和培养法无显著差异，表明两种方法均可用于抗菌效果的研究。
