Department of Conservative Dentistry, Dental Materials Laboratory, School of Dentistry, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2492, Porto Alegre, Rio Grande do Sul 90035-003, Brazil.
Cosmetology Laboratory, School of Pharmaceutical Sciences, Universidade Federal do Rio Grande do Sul, Av. Ipiranga 2752, Porto Alegre, Rio Grande do Sul 90610-000, Brazil.
Dent Mater. 2019 Mar;35(3):457-467. doi: 10.1016/j.dental.2019.01.002. Epub 2019 Jan 11.
The aim of this study was to synthesize and characterize an experimental endodontic paste.
An experimental endodontic paste (EX) was characterized by its particle size, zeta potential, drug content and morphology. The powder of EX is composed of amoxicillin microspheres, calcium tungstate and α-tricalcium phosphate, mixed with an indomethacin nanocapsules suspension. Ultracal (Ultradent), an iodoform-based paste (GP) and the EX were evaluated by its physical properties (flow, film thickness and radiopacity). The cytocompatibility was performed by MTT and SRB-colorimetric assays; the cell-migration was tested with scratch assay and cell-ability to remineralization with ALP and Alizarin Red S, with fibroblastic cell line. The antibacterial activity was assessed by the formation of inhibition zones and against planktonic bacteria.
The EX and UL flow achieved ISO6876 standard, and GP was lower than 17mm. All pastes achieved the film thickness required. Radiopacity was equivalent to 1.81±0.25mmAl for EX, which did not differ from GP group 1.39±0.33mmAl (p>0.05). The UL presented 3.04±0.33mmAl. The values for SRB showed better citocompatibility in comparison with MTT for all materials. The ALP activity and formation of mineralized nodules demonstrated the remineralization potential for UL and EX. Cell migration showed continuous wound closure until complete cell healing, however, the EX accelerated the process (p<0.05). The EX showed the greatest inhibition zone (p<0.05) and was the only group with antibacterial activity against planktonic bacteria.
The synthesized endodontic paste demonstrated reliable physical and biological properties and could be a promising material for periapical tissue repair.
本研究旨在合成和表征一种实验性根管封闭剂。
通过粒径、Zeta 电位、药物含量和形态对实验性根管封闭剂（EX）进行了表征。EX 的粉末由阿莫西林微球、钨酸钙和 α-磷酸三钙组成，混合有吲哚美辛纳米胶囊悬浮液。采用流动度、薄膜厚度和放射密度等物理性能对 Ultral (Ultradent)、基于碘仿的糊剂 (GP) 和 EX 进行了评估。采用 MTT 和 SRB 比色法进行细胞相容性试验；通过划痕试验和碱性磷酸酶（ALP）和茜素红 S 检测细胞矿化能力，检测成纤维细胞系的细胞迁移能力。通过抑菌圈形成和浮游菌对抗评估抗菌活性。
EX 和 UL 的流动度符合 ISO6876 标准，GP 低于 17mm。所有糊剂均达到所需的薄膜厚度。放射密度与 EX 为 1.81±0.25mmAl 相当，与 GP 组 1.39±0.33mmAl（p>0.05）无差异。UL 的放射密度为 3.04±0.33mmAl。与 MTT 相比，SRB 的值显示出更好的细胞相容性。所有材料的 ALP 活性和矿化结节形成均表明 UL 和 EX 具有再矿化潜力。细胞迁移显示连续的伤口闭合，直至完全细胞愈合，但 EX 加速了这一过程（p<0.05）。EX 显示出最大的抑菌圈（p<0.05），并且是唯一对浮游菌具有抗菌活性的组。
合成的根管封闭剂表现出可靠的物理和生物学特性，可能是一种有前途的用于根尖周组织修复的材料。
