Nakhostin Afrooz, Panahandeh Narges, Toudeshky Hossein Hosseini, Sheikh-Al-Eslamian Seyedeh Mahsa
Department of Restorative Dentistry, School of Dentistry, Arak University of Medical Sciences, Arak, Iran.
Dental Research Center, Research Institute of Dental Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
BMC Oral Health. 2025 Apr 16;25(1):579. doi: 10.1186/s12903-025-05769-x.
Creep of composite restorations is affected by their exposure to oral fluids. This study sought to assess the effect of media (water and 75% ethanol) and time storage on creep and compressive strength of bulk-fill and conventional composites.
Twenty-five samples (4 × 6 mm) were fabricated of X-tra fil (bulk-fill) and Estelite Sigma, Grandio SO and Z250 composites (conventional) and divided into five groups (n = 5) according to the storage condition; no storage, 24 h of water storage, 24 h of ethanol storage, 30 days of water storage and 30 days of ethanol storage at 37 °C. Following dynamic creep (1-50 MPa, 0.25 Hz, 30 min, 450 cycles), compressive strength was measured.
Estelite Sigma and Z250 conventional composites showed the highest creep (0.0193 mm and 0.0178 mm, respectively) after 24 h of ethanol storage. GrandioSO had the highest creep (0.0148) after 30 days of ethanol storage (P < 0.05). No difference was noted in creep of X-tra fil when stored in different conditions (P = 0.065). Compressive strength following dynamic force application was in the following order: Z250 > GrandioSO > Estelite and X-tra fil. Storage medium had no significant effect on compressive strength. The highest compressive strength was noted in samples stored for 30 days irrespective of the storage medium.
Alcohol and water storage increased the creep of conventional composites. Creep of bulk-fill composite was not affected by the storage time or medium. Compressive strength of conventional and bulk-fill composites was not influenced by the storage medium but increased over time.
复合树脂修复体的蠕变受其暴露于口腔液体的影响。本研究旨在评估介质（水和75%乙醇）及储存时间对大块充填和传统复合树脂蠕变及抗压强度的影响。
用X-tra fil（大块充填）、Estelite Sigma、Grandio SO和Z250复合树脂（传统型）制作25个样本（4×6毫米），并根据储存条件分为五组（n = 5）；分别为不储存、37℃下储存24小时水、37℃下储存24小时乙醇、37℃下储存30天水和37℃下储存30天乙醇。在动态蠕变（1 - 50兆帕，0.25赫兹，30分钟，450个循环）后，测量抗压强度。
Estelite Sigma和Z250传统复合树脂在储存24小时乙醇后显示出最高蠕变（分别为0.0193毫米和0.0178毫米）。Grandio SO在储存30天乙醇后蠕变最高（0.0148）（P < 0.05）。X-tra fil在不同条件下储存时蠕变无差异（P = 0.065）。施加动态力后的抗压强度顺序如下：Z250 > Grandio SO > Estelite和X-tra fil。储存介质对抗压强度无显著影响。无论储存介质如何，储存30天的样本抗压强度最高。
储存乙醇和水会增加传统复合树脂的蠕变。大块充填复合树脂的蠕变不受储存时间或介质影响。传统和大块充填复合树脂的抗压强度不受储存介质影响，但随时间增加。
