Restorative Dental Sciences Department, College of Dentistry, Taibah University, Madina, Kingdom of Saudi Arabia.
, Riyadh (12252), Kingdom of Saudi Arabia.
BMC Oral Health. 2022 Aug 17;22(1):357. doi: 10.1186/s12903-022-02390-0.
There have been no reports on the impact of different reciprocating angles on retreatment performance of reciprocating files. This ex-vivo study compared the efficiency of three reciprocating systems in removing MTA-type sealer-based filling materials and investigated the influence of different reciprocating angles on their retreatment ability.
140 root-canals were instrumented to a 35 apical size and filled with an MTA-type sealer and gutta-percha cones. Samples were scanned by micro-computed-tomography and the root-canals fillings volumes were measured. Samples were divided into 7 groups according to the reciprocating angles at which the WaveOne-Gold (WOG), Reciproc-Blue (RB) and R-Motion (RM) systems were reciprocated to remove the root-canals' fillings. The WOG-150/30, WOG-90/30, RB-150/30, RB-90/30, RM-150/30 and RM-90/30 groups in which the systems were reciprocated at 150/30 and 90/30 (counterclockwise/clockwise) angles. In the RB-270/30 group the RB system was reciprocated at 270/30 angles. Samples were re-scanned and the remaining filling materials' (RFMs) volumes were measured. The percentage of the RFMs volume and its mean value for each group were calculated and data were statistically analysed at 0.05 significance level.
The WOG system resulted in less RFMs (2.24%) when reciprocated at 90/30 angles compared to that resulted from the 150/30 angles (4.96%) [P = 0.002]. The RB system reciprocated at 90/30 angles resulted in less RFMs (2.67%) compared to that resulted from the 270/30 angles (6.64%) [P = 0.001]. The RFMs after using RM system reciprocated at 90/30 (6.02%) and 150/30 (7.61%) were greater than those of WOG (2.24 and 4.96%) and RB (2.67 and 4.34%) reciprocated at the same angles (P < 0.05). The longest time required to remove the filling materials was recorded with the RB-270/30 group (6.06 min) [P = 0.00]. The times required when the WOG, RB and RM files reciprocated at 90/30 angles (3.59, 3 and 3.05 mins, respectively) were shorter than those when files were reciprocated at 150/30 angles (5.25, 4.98 and 3.67 min, respectively) [P < 0.05].
The WOG and RB systems removed more MTA-type sealer-based root-canals fillings than the RM system. Lower counterclockwise reciprocating angles improve the retreatment ability of reciprocating systems, especially the WOG system and can reduce the time required for retreatment procedures.
目前尚无关于不同往复角度对往复锉再治疗性能影响的报道。本离体研究比较了三种往复系统去除 MTA 型根管封闭剂基充填材料的效率，并研究了不同往复角度对其再治疗能力的影响。
将 140 个根管预备至 35 根尖尺寸，并填充 MTA 型根管封闭剂和牙胶尖。用微计算机断层扫描对样本进行扫描，并测量根管充填体积。根据 WaveOne-Gold (WOG)、Reciproc-Blue (RB) 和 R-Motion (RM) 系统在去除根管充填物时的往复角度，将样本分为 7 组。WOG-150/30、WOG-90/30、RB-150/30、RB-90/30、RM-150/30 和 RM-90/30 组系统以 150/30 和 90/30（逆时针/顺时针）角度往复。在 RB-270/30 组中，RB 系统以 270/30 角度往复。重新扫描样本并测量剩余充填材料（RFM）的体积。计算每个组的 RFM 体积百分比及其平均值，并在 0.05 显著性水平下进行数据统计分析。
与 150/30 角度相比，WOG 系统以 90/30 角度往复时，RFM 体积（2.24%）较少[P=0.002]。与 270/30 角度相比，RB 系统以 90/30 角度往复时，RFM 体积（2.67%）较少[P=0.001]。使用 RM 系统以 90/30（6.02%）和 150/30（7.61%）角度往复时的 RFM 大于 WOG（2.24%和 4.96%）和 RB（2.67%和 4.34%）以相同角度往复时的 RFM（P<0.05）。记录到去除充填材料所需的最长时间是 RB-270/30 组（6.06 分钟）[P=0.00]。WOG、RB 和 RM 锉以 90/30 角度往复时（分别为 3.59、3 和 3.05 分钟）所需的时间短于以 150/30 角度往复时（分别为 5.25、4.98 和 3.67 分钟）[P<0.05]。
与 RM 系统相比，WOG 和 RB 系统去除更多的 MTA 型根管封闭剂基根管充填材料。较低的逆时针往复角度可提高往复系统的再治疗能力，特别是 WOG 系统，并可减少再治疗过程所需的时间。
