Dental Biomaterials Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt.
Industrial Pharmacy Department, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt.
BMC Oral Health. 2024 Sep 14;24(1):1087. doi: 10.1186/s12903-024-04808-3.
Different materials have been used as wound dressings after vital pulp therapies. Some of them have limitations such as delayed setting, difficult administration, slight degree of cytotoxicity, crown discoloration and high cost. Therefore, to overcome these disadvantages, composite scaffolds have been used in regenerative dentistry. This study aims to construct and characterize the physicochemical behavior of a novel injectable alginate hydrogel loaded with different bioactive glass nanoparticles in various concentrations as a regenerative pulpotomy filling material.
Alginate hydrogels were prepared by dissolving alginate powder in alcoholic distilled water containing mesoporous bioactive glass nanoparticles (MBG NPs) or boron-doped MBG NPs (BMBG NPs) at 10 and 20 wt% concentrations. The mixture was stirred and incubated overnight in a water bath at 50 C to ensure complete solubility. A sterile dual-syringe system was used to mix the alginate solution with 20 wt% calcium chloride solution, forming the hydrogel upon extrusion. Then, constructed hydrogel specimens from all groups were characterized by FTIR, SEM, water uptake percentage (WA%), bioactivity and ion release, and cytotoxicity. Statistical analysis was done using One-Way ANOVA test for comparisons between groups, followed by multiple pairwise comparisons using Bonferroni adjusted significance level (p < 0.05).
Alginate/BMBG loaded groups exhibited remarkable increase in porosity and pore size diameter [IIB1 (168), IIB2 (183) (µm)]. Similarly, WA% increased (~ 800%) which was statistically significant (p < 0.05). Alginate/BMBG loaded groups exhibited the strongest bioactive capability displaying prominent clusters of hydroxyapatite precipitates on hydrogel surfaces. Ca/P ratio of precipitates in IIA2 and IIB1 (1.6) were like Ca/P ratio for stoichiometric pure hydroxyapatite (1.67). MTT assay data revealed that the cell viability % of human gingival fibroblast cells have declined with increasing the concentration of both powders and hydrogel extracts in all groups after 24 and 48 h but still higher than the accepted cell viability % of (˃70%).
The outstanding laboratory performance of the injectable alginate/BMBGNPs (20 wt%) composite hydrogel suggested it as promising candidate for pulpotomy filling material potentially enhancing dentin regeneration in clinical applications.
在活髓治疗后，已经使用了不同的材料作为伤口敷料。其中一些具有延迟凝固、给药困难、轻微细胞毒性、冠变色和成本高等局限性。因此，为了克服这些缺点，再生牙科中已经使用了复合支架。本研究旨在构建和表征新型可注射藻酸盐水凝胶的物理化学行为，该水凝胶中负载有不同浓度的生物活性玻璃纳米粒子（MBG NPs）或硼掺杂 MBG NPs（BMBG NPs）。
将藻酸盐粉末溶解在含有中孔生物活性玻璃纳米粒子（MBG NPs）或硼掺杂 MBG NPs（BMBG NPs）的酒精蒸馏水中，浓度分别为 10wt%和 20wt%，制备藻酸盐水凝胶。将混合物搅拌并在 50°C 的水浴中孵育过夜，以确保完全溶解。使用无菌双注射器系统将藻酸盐溶液与 20wt%氯化钙溶液混合，通过挤出形成水凝胶。然后，对所有组别的构建水凝胶标本进行傅里叶变换红外光谱（FTIR）、扫描电子显微镜（SEM）、吸水率（WA%）、生物活性和离子释放以及细胞毒性的表征。使用单因素方差分析（One-Way ANOVA）检验进行组间比较，然后使用 Bonferroni 调整的显著性水平（p<0.05）进行多重两两比较。
负载藻酸盐/BMBG 的组表现出显著增加的孔隙率和孔径直径[IIB1（168），IIB2（183）（µm）]。同样，WA%显著增加（~800%）（p<0.05）。负载藻酸盐/BMBG 的组表现出最强的生物活性能力，在水凝胶表面显示出大量羟磷灰石沉淀物的聚集。沉淀的 Ca/P 比在 IIA2 和 IIB1（1.6）中与化学计量纯羟磷灰石（1.67）的 Ca/P 比相似。MTT 测定数据显示，在 24 和 48 h 后，人牙龈成纤维细胞的细胞活力%随着两种粉末和所有组的水凝胶提取物浓度的增加而下降，但仍高于可接受的细胞活力%（>70%）。
可注射藻酸盐/BMBGNPs（20wt%）复合材料水凝胶的出色实验室性能表明，它可能作为一种有前途的活髓治疗填充材料，在临床应用中潜在地增强牙本质再生。
