Shafiei Fereshteh, Tavangar Maryam S
Department of Operative Dentistry, School of Dentistry, Oral and Dental Disease Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
Clin Exp Dent Res. 2024 Aug;10(4):e936. doi: 10.1002/cre2.936.
Sodium hypochlorite solution (NaOCl) is an effective canal irrigant but interferes with the mechanical features of dentin and the bonding capability of adhesives when restoring endodontically treated teeth. This study evaluated whether access cavity resin sealing before using canal irrigant would augment the resistance of endodontically treated anterior teeth against fracture.
Sixty maxillary incisors underwent endodontic treatment in five groups (n = 12). Irrigation with 5.25% NaOCl and 17% ethylenediaminetetraacetic acid (EDTA) was performed in all groups except for Group 5. After root canal obturation, in Group 1, the access cavity was kept unrestored. In Group 2, immediate restoration after obturation was achieved. For Group 3, delayed restoration after 1 week was provided. In Group 4 (pre-sealed), before canal irrigation, the dentin surface of access cavities was sealed using self-adhesive composite resin (Vertise Flow) and then restored after obturation. In Group 5, which was saline irrigated, immediate restoration was performed. After storage and thermal cycling for 5000 cycles at 5°C-55°C with a dwell time of 15 s and a transfer time of 5 s, teeth were statically loaded by a universal testing machine until a fracture occurred. Data were collected as the fracture resistance (FR) and analyzed using the one-way analysis of variance and Tukey's tests.
FR significantly differed between all groups (p < 0.001). The lowest FR was recorded in the unrestored group (284 ± 86 N), which was not statistically different from the immediately restored group (p = 0.065). The pre-sealed group exhibited the highest FR value (810 ± 127 N, p ≤ 0.02 vs. other groups). The FR of the saline-irrigated and delayed restored groups was almost similar (p = 0.13).
NaOCl/EDTA irrigation resulted in an adverse effect on FR. Delayed restoration could reduce this adverse effect. Access cavity pre-sealing with flowable composites led to a higher FR than conventional methods and may be considered an effective step during treatment procedures.
次氯酸钠溶液（NaOCl）是一种有效的根管冲洗剂，但在修复根管治疗后的牙齿时，会影响牙本质的机械性能和粘结剂的粘结能力。本研究评估在使用根管冲洗剂之前进行髓腔树脂封闭是否会增强根管治疗后前牙的抗折性。
60颗上颌切牙分为五组（n = 12）进行根管治疗。除第5组外，所有组均用5.25% NaOCl和17%乙二胺四乙酸（EDTA）冲洗。根管充填后，第1组髓腔未作处理；第2组充填后立即修复；第3组充填1周后延迟修复；第4组（预封闭组）在根管冲洗前，用自粘结复合树脂（Vertise Flow）封闭髓腔牙本质表面，充填后再修复；第5组用生理盐水冲洗，充填后立即修复。在5°C - 55°C下储存并进行5000次热循环，保压时间15 s，转换时间5 s，然后用万能试验机对牙齿进行静态加载直至折断。收集抗折强度（FR）数据，采用单因素方差分析和Tukey检验进行分析。
所有组的FR有显著差异（p < 0.001）。未处理组的FR最低（284 ± 86 N），与立即修复组无统计学差异（p = 0.065）。预封闭组的FR值最高（810 ± 127 N，与其他组相比p ≤ 0.02）。生理盐水冲洗组和延迟修复组的FR几乎相似（p = 0.13）。
NaOCl/EDTA冲洗对FR有不良影响。延迟修复可减少这种不良影响。用可流动复合树脂预封闭髓腔比传统方法能获得更高的FR，可被视为治疗过程中的有效步骤。
