様々な潅水システムを用いた根管内水酸化カルシウム除去の評価。SEMによる研究

Assessment of Intracanal Calcium Hydroxide Removal Using Various Irrigation Systems: An SEM Study.

抄録

目的:

本研究の目的は、根管からの水酸化カルシウム[Ca(OH)]の除去における3つの異なる灌流システムの有効性を評価することであった。

AIM: The aim of this research was to assess the effectiveness of three different irrigation systems in elimination of calcium hydroxide [Ca(OH)]from root canals.

材料と方法:

本研究では、最近抜歯した下顎前歯の単根90本を対象とした。サンプル歯は5.25％の次亜塩素酸ナトリウムで消毒された。根管治療を行った後、すべての根管にCa(OH)を添加した。次に，試料歯を以下の3つの実験グループのいずれかに無作為に割り付けた（各グループは30試料からなる）．グループ1：NaviTip FX灌流システム、グループ2：Vibringeソニック灌流システム、グループ3：EndoVac先端負圧灌流システム。各サンプル歯は、調製後、走査型電子顕微鏡（SEM）により1000倍の倍率で観察した。

MATERIALS AND METHODS: This research included ninety recently extracted mandibular premolar teeth with a solitary root. The sample teeth were subjected to disinfection employing sodium hypochlorite at 5.25%. The root canal preparation was performed followed by placement of premixed Ca(OH) within every canal. The sample teeth were then randomly allocated into one of the three experimental groups (each comprising 30 samples) as follows: Group 1, NaviTip FX irrigation system; group 2, Vibringe sonic irrigation system; and group 3, EndoVac apical negative pressure irrigation system. Following the preparation, each of the sample teeth was examined beneath a scanning electron microscope (SEM) at a magnification of 1000×.

結果:

グループ内比較分析の結果、NaviTip FX irrigation systemとVibringe sonic irrigation systemでは、それぞれ中段3分の1で最も高いCa（OH）除去率が見られた（0.82 ± 0.09, 0.30 ± 0.11 ）。エンドバックイリゲーションシステムでは、頂部3分の1でより高いCa(OH)が除去された（0.26±0.02）。冠状3rdでは、EndoVac irrigation systemで最大のCa(OH)除去が認められた（0.49±0.03）。Vibringe sonic irrigationとEndoVac irrigationの間に統計学的に有意な差が認められた。冠状部、中間部、先端部におけるCa(OH)除去のグループ間評価では、NaviTip FX灌漑とVibringe sonic灌漑、NaviTip FX灌漑とEndoVac灌漑の間で、0.001の値で統計的に有意差が見られた。EndoVacとVibringeの間の差は、統計的に有意でなかった。

RESULTS: An intragroup comparative analysis revealed that the highest Ca(OH) elimination was seen at middle third (0.82 ± 0.09, 0.30 ± 0.11) in NaviTip FX irrigation system and Vibringe sonic irrigation system, respectively. Higher Ca(OH) was eliminated at the apical third (0.26 ± 0.02) by the EndoVac irrigation system. At coronal third, maximum Ca(OH) removal was seen in EndoVac irrigation system (0.49 ± 0.03). A statistically significant difference was noted amid Vibringe sonic irrigation and EndoVac irrigation systems. The intergroup evaluation of Ca(OH) elimination at coronal, middle, and apical third showed a statistically significant difference between NaviTip FX irrigation and Vibringe sonic irrigation as well as between NaviTip FX irrigation and EndoVac irrigation at a value of 0.001. The difference between EndoVac irrigation and Vibringe sonic irrigation was not statistically significant.

結論:

本研究の限界の中で、本研究は、採用した潅漑方法のいずれも根管内のCa(OH)を完全に除去することはできないと結論づけた。しかし、エンドバック先端部陰圧灌流は、Vibringe sonic irrigationおよびNaviTip FX irrigation systemと比較して、根管からのCa(OH)の除去にやや優れた可能性を有している。

CONCLUSION: Amid the limitations of this research, this research concludes that none among the irrigation methods employed could totally eliminate the Ca(OH) off the root canals. Nevertheless, EndoVac apical negative pressure irrigation has slightly superior potential in eliminating Ca(OH) from the root canals in comparison with Vibringe sonic irrigation as well as the NaviTip FX irrigation system.

臨床的意義:

歯周病治療において，Ca(OH)は薬として使用されることが多いが，管腔閉鎖時の除去も重要であり，残存部分があると象牙細管内のシーラー拡散を妨げ，歯内漏出を増大させる．

CLINICAL SIGNIFICANCE: Even though the Ca(OH) is largely suggested as medicament, its elimination at the point of canal obturation is likewise significant and complex as any remaining portion may avoid sealer diffusion inside the dentinal tubules, consequently substantially escalating the apical leakage of endodontically treated teeth.