Ezzat Dina, Sheta Mai Samy, Kenawy El-Refaie, Eid Mohammed A, Elkafrawy Hend
Dental Biomaterials Department, Faculty of Dentistry, Tanta University, El-Geish Street, Tanta, 31511, Egypt.
Chemistry Department, Faculty of Science, Tanta University, Tanta, Egypt.
Odontology. 2025 Feb 17. doi: 10.1007/s10266-025-01058-9.
Dental composite resins often face challenges related to secondary caries, polymerization shrinkage and fracture failure. This study aimed to synthesize an experimental composite resin modified with grapefruit seed extract-mediated titanium dioxide nanoparticles (GSE-TiO₂NPs) and evaluate its antibacterial activity and mechanical and physical properties. Green synthesis of TiO₂ nanoparticles was conducted utilizing GSE. The chemical profile of GSE was identified through gas chromatography-mass spectrometry. The as-prepared nanoparticles were incorporated into experimental composites at concentrations of 10 wt.% (10 wt.% GSE-TiO₂NPs group) and 20 wt.% (20 wt.% GSE-TiO₂NPs group), with an unmodified composite as the control group. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirmed the morphology and size of synthesized nanoparticles, with SEM revealing uniform particle distribution in the composite. Antibacterial activity against Streptococcus mutans was assessed using the agar disc diffusion method. Mechanical properties, including flexural strength (FS) and flexural modulus (FM), were evaluated according to ISO 4049 standards. Microhardness was tested according to the American Society for Testing Materials (ASTM E-384:1999) criteria. Polymerization shrinkage was measured using the strain gauge method. Modified composites exhibited significantly greater antibacterial activity against S. mutans compared to the control (p < 0.001). The 10 wt.% GSE-TiO₂NPs group demonstrated increased FS and FM values compared to the control group (p < 0.05). All groups surpassed the clinically acceptable microhardness threshold without significant differences (p = 0.588). Polymerization shrinkage was reduced in the modified groups (p < 0.01), with the 20 wt.% GSE-TiO₂NPs group showing the lowest value (13.06 ± 0.92%). Incorporating GSE-TiO₂NPs into composite resins enhances antibacterial activity, improves mechanical properties, and reduces polymerization shrinkage, suggesting a promising approach for developing advanced dental materials with integrated natural bioactive components.
牙科复合树脂常常面临与继发龋、聚合收缩和断裂失效相关的挑战。本研究旨在合成一种用葡萄柚籽提取物介导的二氧化钛纳米颗粒（GSE-TiO₂NPs）改性的实验性复合树脂，并评估其抗菌活性以及机械和物理性能。利用葡萄柚籽提取物进行二氧化钛纳米颗粒的绿色合成。通过气相色谱-质谱法确定葡萄柚籽提取物的化学特征。将制备好的纳米颗粒以10重量%（10重量% GSE-TiO₂NPs组）和20重量%（20重量% GSE-TiO₂NPs组）的浓度掺入实验性复合材料中，以未改性的复合材料作为对照组。扫描电子显微镜（SEM）和透射电子显微镜（TEM）证实了合成纳米颗粒的形态和尺寸，SEM显示颗粒在复合材料中分布均匀。采用琼脂圆盘扩散法评估对变形链球菌的抗菌活性。根据ISO 4049标准评估包括弯曲强度（FS）和弯曲模量（FM）在内的机械性能。根据美国材料与试验协会（ASTM E-384:1999）标准测试显微硬度。使用应变片法测量聚合收缩。与对照组相比，改性复合材料对变形链球菌表现出显著更强的抗菌活性（p < 0.001）。与对照组相比，10重量% GSE-TiO₂NPs组的FS和FM值有所增加（p < 0.05）。所有组均超过了临床上可接受的显微硬度阈值，且无显著差异（p = 0.588）。改性组的聚合收缩降低（p < 0.01），20重量% GSE-TiO₂NPs组的值最低（13.06 ± 0.92%）。将GSE-TiO₂NPs掺入复合树脂中可增强抗菌活性、改善机械性能并降低聚合收缩，这表明开发具有集成天然生物活性成分高级牙科材料的一种有前景的方法。
