扭力值增加對ProFile的影響

Influence of Increased Torque on the ProFile

劉季煒(Ji-Uei Liou) ； 杜博仁(Bor-Ren Duh) ； 林上人(Sun-Jen Lin) ； 鄭安芝(An-Chih Chung) ； 陳立盛(Li-Shun Cheng)

《中華牙醫學雜誌》 22卷4期 (2003/12) Pp. 345-350

摘要

Ni-Ti engine-driven rotary instruments are increasingly being used in endodontic practice. Cutting is much easier and efficient when a Ni-Ti rotary instruments is used for root canal preparation. During root canal preparation, instruments may be locked and threaded into the canal wall; however, locked instruments are subjected to high levels of stress, frequently leading to separation. This study used Anthogyr Ni-Ti control Contra-angle and ATR motor (TECNKA, Dentsply, USA) with a size #25 file, a taper 0.04 ProFile, and a resin block of 30. (ISO 0.02 taper, 015). The purpose of this study was to evaluate the influence of increasing torque on the ProFile with the same rotational speed and force. Each group had 7 files: Group I , (T of 15 Ncm); Group II, increased the torque by 25% (T of 19 Ncm); Group III, increased the torque by 50% (T of 23 Ncm) All groups of files were used to prepare canals of resin blocks to their working length, and then a new one was prepared and over and over until the file separated. Then we counted the number of finished resin blocks in each group, and the number of times that the files had been used. There was a statistically significant difference in the number of finished resin blocks and working times before file separation in the group with 50% increased torque (group III) compared to the others. There was a statistically significant difference in the working times of single resin block finished preparations among the 3 groups (p＜0.005, by ANOVA). According to results of this study, we suggest increasing the torque by 25% when using a size #25 file and a taper 0.04 ProFile for root canal preparations.

關鍵字

扭力值 ； 鎳鈦

並列摘要

Ni-Ti engine-driven rotary instruments are increasingly being used in endodontic practice. Cutting is much easier and efficient when a Ni-Ti rotary instruments is used for root canal preparation. During root canal preparation, instruments may be locked and threaded into the canal wall; however, locked instruments are subjected to high levels of stress, frequently leading to separation. This study used Anthogyr Ni-Ti control Contra-angle and ATR motor (TECNKA, Dentsply, USA) with a size #25 file, a taper 0.04 ProFile, and a resin block of 30. (ISO 0.02 taper, 015). The purpose of this study was to evaluate the influence of increasing torque on the ProFile with the same rotational speed and force. Each group had 7 files: Group I , (T of 15 Ncm); Group II, increased the torque by 25% (T of 19 Ncm); Group III, increased the torque by 50% (T of 23 Ncm) All groups of files were used to prepare canals of resin blocks to their working length, and then a new one was prepared and over and over until the file separated. Then we counted the number of finished resin blocks in each group, and the number of times that the files had been used. There was a statistically significant difference in the number of finished resin blocks and working times before file separation in the group with 50% increased torque (group III) compared to the others. There was a statistically significant difference in the working times of single resin block finished preparations among the 3 groups (p＜0.005, by ANOVA). According to results of this study, we suggest increasing the torque by 25% when using a size #25 file and a taper 0.04 ProFile for root canal preparations.

並列關鍵字

torque ； Ni-Ti ； ProFile