Department of Restorative, Preventive and Pediatric Dentistry, School of Dental Medicine, University of Bern, Freiburgstrasse 7, 3010, Bern, Switzerland.
Department of Periodontology and Operative Dentistry, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany.
BMC Oral Health. 2021 Feb 16;21(1):74. doi: 10.1186/s12903-021-01431-4.
Tooth fractures can occur after temporary inter-appointment endodontic filling, resulting in not preserving and thus extraction of the affected tooth. The purpose of this investigation was therefore to evaluate the tooth substance fracture potential given by the expansion of endodontic temporary filling materials.
Tooth and access cavities were prepared in 80 mandibular molars. Four groups of 20 teeth each (Cavit, Cavit W and Coltosol F and control) were included. To simulate a clinical situation, the teeth were endodontically pre-treated and a calcium hydroxide dressing was placed. The cavities were filled with the corresponding temporary filling material, with exception of the control group, and kept submerged in distilled water for 15 days. The teeth were examined every 24 h by two calibrated observers under a stereomicroscope (7.5×), fractures of the temporary filling material and tooth structure were photo-documented, and the results statistically analyzed. Kaplan-Meier survival analysis were calculated to illustrate (survival = no fracture) probabilities to evaluate the time when the temporary filling material, tooth structure or both together occurred. Log-rank test was performed in order to assess significant differences between the materials and the subgroups used.
Fractures were observed only in the Coltosol F group (p < 0.01), at the end of the observation period, a total of 13 teeth (65%) showed temporary filling material and eight teeth (40%) showed tooth structure fractures. No fractures in the pulp chamber area were observed at the end of the observation period in any group.
Within the limitations of the current in vitro study, the results obtained suggest that tooth structure fractures caused by a temporary filling material can occur during endodontic treatment, thus compromising the success of the treatment.
临时根管封填后可能发生牙折，导致患牙无法保留而被拔除。本研究旨在评估根管暂封材料膨胀对牙体折裂的潜在影响。
在 80 颗下颌磨牙上制备牙体和开髓腔，共 40 个样本，每组 20 个（Cavit、Cavit W、Coltosol F 和对照组）。为模拟临床情况，对牙齿进行根管预处理并放置氢氧化钙糊剂，用相应的暂封材料充填窝洞，除对照组外，所有样本均在蒸馏水中浸泡 15 天。每隔 24 小时，由两名经过校准的观察者在立体显微镜（7.5×）下检查牙齿，拍照记录暂封材料和牙体结构的折裂情况，并对结果进行统计学分析。采用 Kaplan-Meier 生存分析来描述（生存=无折裂）以评估暂封材料、牙体结构或两者同时发生的时间，并采用对数秩检验来评估不同材料和亚组之间的差异。
仅在 Coltosol F 组观察到折裂（p<0.01），在观察期末，共有 13 颗牙（65%）出现暂封材料折裂，8 颗牙（40%）出现牙体结构折裂。在观察期末，各组牙髓腔区域均未观察到折裂。
在本体外研究的限制内，结果表明在根管治疗过程中，暂封材料可能导致牙体结构折裂，从而影响治疗的成功。
