湾曲根管形成を模擬した模擬レジンを作製するための4種類のニッケルチタン製器具の能力を比較した

[Comparison of the ability of four different kinds of nickel-titanium instruments to prepare simulated resin to simulate curved root canal forming].

抄録

目的:

4種類のニッケルチタン製器具による模擬湾曲根管形成用レジンの作製能力を比較すること。

PURPOSE: To compare the forming ability of four kinds of nickel-titanium instrument preparation resin for simulated curved root canal.

方法:

シングルベンドレジン模擬根管40本を無作為に4群に分け、各群10本とした。根管形成には4種類のニッケルチタン製器具（ProTaper、HyFlex EDM、WaveOne Gold、Reciproc Blue）を使用し、A群、B群、C群、D群に分けた。4群の形成時間を比較し、形成前後の根管画像をコンピュータ画像解析ソフトで解析し、4群の形成時間、曲率、曲率半径の変化を記録した。根尖を円の中心とし、半径1～10mmを同心円の円弧とした。検出点はオーバーラップする根管交点とした。異なる検出点における根管内壁と外壁のレジン除去量と中心位置決め力を記録した．統計分析はSPSS 20.0ソフトウェアパッケージで行った。

METHODS: A total of 40 single bend resin simulated root canals were randomly divided into 4 groups with 10 in each group. Four kinds of nickel-titanium instruments (ProTaper, HyFlex EDM, WaveOne Gold and Reciproc Blue) were used for root canal preparation, and divided into group A, group B, group C and group D. The preparation time of the four groups was compared, the root canal images before and after preparation were analyzed by computer image analysis software, and the changes of the preparation time, curvature and curvature radius of the four groups were recorded. With the root tip as the center of the circle, the radius of 1-10 mm was selected as concentric circle arcs. The detection points were overlapping root canal intersection points. The resin removal amount and center positioning force of the inner and outer walls of the root canal at different detection points were recorded. Statistical analysis was performed with SPSS 20.0 software package.

結果:

A群の根管準備時間はB群、C群、D群より有意に長かったが（P＜0.05）、根管の曲率および曲率半径には4群間で有意差はなかった（P＞0.05）。C群の根管壁からのレジン除去量は，検出点から根尖孔までの距離がそれぞれ5，6，8，9，10 mmのとき，A，B，D群より有意に少なかった（P＜0.05）．C群の根管外壁からのレジン除去量は，検出点から根尖孔までの距離がそれぞれ5，6，7，9，10 mmのとき，A，B，D群より有意に少なかった（P＜0.05）．検出点から根尖孔までの距離が1, 2, 3, 4, 6, 7, 8, 9, 10 mmのA群の根尖オフセットは、B, C, D群よりも有意に大きかった(P＜0.05)。

RESULTS: The root canal preparation time in group A was significant longer than that in group B, C and D(P＜0.05), but there was no significant difference in the curvature and curvature radius of the root canal among the four groups (P＞0.05). The removal amount of resin from the root canal wall in group C was significant lower than that in group A, B and D (P＜0.05) when the distance from the detection point to the apical foramina was 5, 6, 8, 9 and 10 mm, respectively. The removal amount of resin from the outer wall of the root canal in group C was significant lower than that in group A, B and D (P＜0.05) when the distance from the detection point to the apical foramina was 5, 6, 7, 9 and 10 mm, respectively. The root tip offset of group A from the detection point to the apical hole of 1, 2, 3, 4, 6, 7, 8, 9 and 10 mm was significant greater than that of group B, C and D(P＜0.05).

結論:

4つのインスツルメントのうち、ProTaperは根尖偏位が最も大きく、HyFlex EDM、WaveOne Gold、Reciproc Blueは根管形成能に優れていた。

CONCLUSIONS: Among the four instruments, ProTaper has the largest apical deviation, HyFlex EDM, WaveOne Gold and Reciproc Blue have better ability of root canal forming.