Liu Yuxuan, Luo Yi, Feng Yaxu, Gao Xianhua, Fan Wei, Fan Bing
State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, Wuhan University, Wuhan, People's Republic of China.
State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, Wuhan University, Wuhan, People's Republic of China.
J Endod. 2025 Apr;51(4):499-506. doi: 10.1016/j.joen.2024.12.014. Epub 2024 Dec 26.
This study aimed to assess the effect of cavity designs on instrumentation, obturation and fracture resistance for mandibular first premolars with Vertucci V canal.
Mandibular first premolars with Vertucci V canal were scanned with microcomputed tomography. A total of 20 teeth with moderately curved canal were prepared with conservative endodontic cavity (CEC/M) or traditional endodontic cavity (TEC/M), and 30 with severely curved canal were prepared with CEC (CEC/S), modified CEC (MCEC/S) or TEC (TEC/S). CECs and MCEC were prepared using dynamic navigation systems. TECs were prepared freehand. Canals were prepared with WaveOne Gold, irrigated and then obturated with single-cone technique using iRoot SP sealer and WaveOne Gold gutta-percha cones. After restoration, all teeth were submitted to fracture resistance test. Removal of pericervical dentin, volume of dentin removal, area of untouched canal wall, accumulated hard tissue debris, centering ability, voids in canal filling, and load at fracture were evaluated.
MCEC and CEC groups preserved more pericervical dentin above the alveolar bone level and more fracture resistance than TEC groups. At 3 mm from apical foramen, lower centering ability in mesiodistal direction was found in buccal canal of CEC/S group. More voids were found in the lingual canal for CEC/S compared with TEC/S (P < .05).
CEC and MCEC prepared with dynamic navigation system could preserve more dentin above the alveolar bone and fracture resistance than TEC prepared freehand. For teeth with severely curved V canal, MCEC showed similar ability in instrumentation and obturation as TEC.
本研究旨在评估洞形设计对具有Vertucci V型根管的下颌第一前磨牙根管预备、充填及抗折性能的影响。
采用显微计算机断层扫描技术对具有Vertucci V型根管的下颌第一前磨牙进行扫描。选取20颗根管中度弯曲的牙齿，分别采用保守性根管治疗洞形（CEC/M）或传统根管治疗洞形（TEC/M）进行预备；30颗根管重度弯曲的牙齿，分别采用CEC（CEC/S）、改良CEC（MCEC/S）或TEC（TEC/S）进行预备。CEC和MCEC采用动态导航系统进行预备，TEC采用徒手预备。使用WaveOne Gold器械预备根管，冲洗后采用iRoot SP封闭剂和WaveOne Gold牙胶尖进行单尖法充填。修复后，对所有牙齿进行抗折性能测试。评估颈周牙本质去除量、牙本质去除体积、未触及的根管壁面积、累积硬组织碎屑、定心能力、根管充填中的空隙以及抗折载荷。
MCEC组和CEC组在牙槽骨水平以上保留了更多的颈周牙本质，且抗折性能优于TEC组。在距根尖孔3mm处，CEC/S组颊侧根管在近远中方向的定心能力较低。与TEC/S组相比，CEC/S组舌侧根管中的空隙更多（P <.05）。
与徒手预备的TEC相比，采用动态导航系统预备的CEC和MCEC在牙槽骨水平以上能保留更多牙本质，且抗折性能更好。对于根管重度弯曲的V型根管牙齿，MCEC在根管预备和充填方面表现出与TEC相似的能力。
