Department of Cariology, Restorative Sciences and Endodontics, University of Michigan School of Dentistry, Ann Arbor, Michigan, 48109.
Department of Clinical Dentistry (Endodontics), Federal University of Bahia, Salvador, Bahia, 40110, Brazil.
J Biomed Mater Res B Appl Biomater. 2019 Jul;107(5):1576-1586. doi: 10.1002/jbm.b.34250. Epub 2018 Oct 3.
Evoked bleeding (EB) clinical procedure, comprising a disinfection step followed by periapical tissue laceration to induce the ingrowth of undifferentiated stem cells from the periodontal ligament and alveolar bone, is currently the only regenerative-based therapeutic approach to treating pulp tissue necrosis in undeveloped (immature) permanent teeth approved in the United States. Yet, the disinfection step using antibiotic-based pastes leads to cytotoxic, warranting a biocompatible strategy to promote root canal disinfection with no or minimal side-effects to maximize the regenerative outcomes. The purpose of this investigation was to develop a tubular three-dimensional (3D) triple antibiotic-eluting construct for intracanal drug delivery. Morphological (scanning electron microscopy), chemical (Fourier transform infrared spectroscopy), and mechanical (tensile testing) characteristics of the polydioxanone-based triple antibiotic-eluting fibers were assessed. The antimicrobial properties of the tubular 3D constructs were determined in vitro and in vivo using an infected (Actinomyces naeslundii) dentin tooth slice model and a canine method of periapical disease, respectively. The in vitro data indicated significant antimicrobial activity and the ability to eliminate bacterial biofilm inside dentinal tubules. In vivo histological findings demonstrated that, using the EB procedure, the tubular 3D triple antibiotic-eluting construct allowed the formation of an appropriate environment that led to apex closure and the ingrowth of a thin layer of osteodentin-like tissue into the root canal. Taken together, these findings indicate that our novel drug delivery construct is a promising biocompatible disinfection strategy for immature permanent teeth with necrotic pulps. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1576-1586, 2019.
诱发出血（EB）临床操作，包括消毒步骤，随后进行根尖组织切开，以诱导牙周韧带和牙槽骨中的未分化干细胞生长，是目前唯一在美国获得批准的、基于再生的治疗未发育（不成熟）恒牙牙髓组织坏死的治疗方法。然而，使用基于抗生素的糊剂进行消毒会导致细胞毒性，因此需要一种生物相容性策略来促进根管消毒，以达到最小的副作用或无副作用，从而最大限度地提高再生效果。本研究旨在开发一种管状三维（3D）三重抗生素洗脱构建体，用于根管内药物输送。评估了基于聚二恶烷酮的三重抗生素洗脱纤维的形态学（扫描电子显微镜）、化学（傅里叶变换红外光谱）和机械（拉伸试验）特性。使用感染（奈瑟放线菌）牙本质牙切片模型和犬类根尖疾病方法，分别在体外和体内评估管状 3D 结构的抗菌性能。体外数据表明，该管状 3D 三重抗生素洗脱构建体具有显著的抗菌活性和消除牙本质小管内细菌生物膜的能力。体内组织学研究结果表明，使用 EB 操作，管状 3D 三重抗生素洗脱构建体能形成适当的环境，导致根尖闭合，并在根管内生长一层薄的类骨牙本质样组织。综上所述，这些发现表明，我们的新型药物输送构建体是一种有前途的生物相容性消毒策略，可用于治疗坏死牙髓的不成熟恒牙。© 2018 威利父子公司。J 生物医学材料研究部分 B：应用生物材料 107B: 1576-1586, 2019.
