腔内Enterococcus faecalis個体群の減少における音波洗浄法と2種類の超音波洗浄法の抗菌効果の比較

Comparison of the antibacterial efficacy of sonic- and two ultrasonic-activated irrigation techniques in reducing intracanal Enterococcus faecalis populations.

抄録

目的:

この In-vitro 試験では、Enterococcus faecalis に感染した根管において、音波灌流および超音波灌流による抗菌効果を断続的または連続的に評価した。

OBJECTIVE: This in-vitro study evaluated the antibacterial efficacy of sonic and ultrasonic irrigation with either intermittent or continuous flush in root canals infected with Enterococcus faecalis.

方法と材料:

FlexMaster NiTi-instrumentsを用いて直根管70本の単根抜去歯を作製し、滅菌後、E faecalisを接種し、72時間培養した。60本の歯根を無作為に4つの実験群と感染群、無菌対照群に分けた（各n = 10）。残りの歯は、塗抹層除去（n = 5）およびE faecalisによる感染（n = 5）のSEM分析に使用した。実験群の灌流は、1％NaOClとシリンジ灌流、EndoActivatorによる灌流液の音波活性化、断続的なフラッシュを伴う超音波活性化、または連続的なフラッシュを伴う超音波活性化で行った。微生物サンプリングは、根管壁から象牙質の削り屑を採取して行った。コロニー形成単位をカウントし、縦断的データについてノンパラメトリック順位ベースのANOVA型検定を用いて統計解析を行った（P < .05）。

METHOD AND MATERIALS: Seventy single-rooted, extracted teeth with straight root canals were prepared with FlexMaster NiTi-instruments, sterilized, inoculated with E faecalis and incubated for 72 hours. Sixty roots were randomly divided into four experimental groups as well as into infection and sterile controls (n = 10 each). The remaining teeth were used for SEM analysis of smear layer removal (n = 5) and infection with E faecalis (n = 5). Irrigation in the experimental groups was performed with 1% NaOCl and syringe irrigation, sonic activation of the irrigant with EndoActivator, ultrasonic activation with intermittent flush, or ultrasonic activation with continuous flush. Microbial sampling was performed by collecting dentin shavings from the root canal walls. Colony-forming units were counted and statistical analysis was performed using nonparametric rank-based ANOVA-type tests for longitudinal data (P < .05).

結果:

すべての灌流法で、E faecalisが感染対照と比較して3 log10段階有意に減少した（P < 0.0001）。シリンジ灌流、超音波灌流、超音波活性化灌流のいずれにおいても、抗菌効果に有意差は認められなかった（P > 0.45）。

RESULTS: A significant reduction of E faecalis of 3 log10 steps compared to the infection control was achieved by all irrigation techniques (P < .0001). There were no significant differences in antibacterial efficacy between syringe irrigation, sonically, or ultrasonically activated irrigation (P > .45).

結論:

音波または超音波装置による1％NaOClの活性化は、直根管における従来のシリンジ潅注と比較して、E faecalisに対する抗菌効果を増加させなかった。

CONCLUSION: Activation of 1% NaOCl with either sonic or ultrasonic devices did not increase the antimicrobial efficacy against E faecalis compared to conventional syringe irrigation in straight root canals.