OPTIMIZATION OF OSTEOGENIC PROTEIN 1 FOR DENTINOGENESIS

优化成牙本质蛋白 1

基本信息

批准号：
2422141
负责人：
R B Rutherford
金额：
$ 10万
依托单位：
CREATIVE BIOMOLECULES, INC.
依托单位国家：
美国
项目类别：
财政年份：
1997
资助国家：
美国
起止时间：
1997-09-30 至 1999-09-29
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/2422141
关键词：
bone regeneration dental disorder chemotherapy dentinogenesis dosage drug design /synthesis /production drug screening /evaluation ferrets histology immunocytochemistry in situ hybridization nonhuman therapy evaluation pulp disorder transforming growth factors

项目摘要

DESCRIPTION: Insults to the dental pulp tissues, in the form of trauma, caries, tooth preparation, or bacterial leakage around restorative materials can result in several sequelae, including the formation of "protective" reparative dentin, chronic inflammatory cell infiltrates within the pulp tissues with clinical symptoms, or frank pulpal necrosis. The latter two conditions may necessitate root canal therapy. Severe wear of the dentition, or loss of substantial tooth structure via repeated restorative procedures and/or caries may result in a tooth with a vital pulp that has insufficient remaining tooth structure to retain the planned restorative material. Consequently, estimates exist that between 20 and 30% of teeth requiring root canal therapy have vital pulps, the root canal therapy being required solely to provide enhanced retention of the restorative material by utilizing the anatomy of the root canal space. Genetically engineered materials may have the ability to promote dentin formation lateral to the root canal space, rather than at its expense, which could lead to a significant reduction in the numbers of teeth requiring root canal therapy nationally. OPs and bone morphogenetic proteins (BMPs) comprise a subgroup of the TGF-B superfamily; proteins from this family have demonstrated diverse biological activities, including differentiation, tissue morphogenesis, regeneration, and repair. Recombinant human OP-1, when complexed with an insoluble type I collagen matrix (CM), has been shown to be a potent stimulator of reparative dentinogenesis. Previous studies by the principal investigator in noncarious teeth of nonhuman primates has demonstrated that exposed pulp tissue responded to the use of 2.5 ug of OP-1 per mg of CM by fibroblastic and angiogenic invasion of the material, resulting in a mineralizing mass of new pulp tissue which formed in place of (and which replaced) the OP-1/CM. In addition, the reparative dentin was formed superficial to (rather than at the expense of) the existing pulp tissues, and the amount of reparative dentin formed was proportional to the total mass of the OP-1/CM placed on the exposed pulp. Finally, mineralization of the reparative dentin was 95% complete by 6 months. The OP-1/CM material apparently provides the potential to regenerate the dentin component of missing tooth structure, rather than replace it with restorative dental materials. However, all studies to date have focused on noncarious teeth with normal pulpal architecture and vitality. The specific aims of this proposal are 1) to optimize conditions for inducing coronal pulpitis in baboon teeth; 2) to characterize the inflammatory response, and 3) to optimize the concentration of OP-1/unit mass of CM for induction of reparative dentinogenesis in radicular pulp tissue deep to inflamed coronal pulps. Specific Aims 1 and 2: Pilot experiments will test the ability of different concentrations of LPS placed on exposed and amputated dental pulps to induce pulpitis. Specific Aim 3: Four animals will provide a total of 65 teeth for evaluation of the OP-1/CM response to "infected" pulp tissues. Following the induction of pulpitis, the teeth will be reopened, the surgical site cleansed mechanically and rinsed with sterile saline, the access to the pulp chamber enlarged, and all coronal pulp tissue removed with dental rotary instruments. OP-1/CM concentrations of 2.5, 7.5, and 25 ug/mg will be placed over the exposed root tissues. Control groups include placement of 2.5 ug/mg OP-1/CM control in a "sham infected" tooth, and placement of CM alone. All teeth will be restored with a glass ionomer base, varnish, and amalgam. Tissue samples will be collected after 4 weeks. Conventional histology (H&E, Masson's Trichrome, and von Kossa's), histomorphometry, and immunohistochemistry will be performed using prescribed techniques. All experimentation is expected to conclude within 6-7 months.

描述：以创伤的形式损害牙髓组织，龋齿、牙齿预备或修复体周围的细菌渗漏材料可能会导致多种后遗症，包括形成 “保护性”修复牙本质，慢性炎症细胞浸润有临床症状的牙髓组织内，或明显的牙髓坏死。后两种情况可能需要根管治疗治疗。牙列严重磨损，或大量牙齿脱落通过重复的修复程序和/或可能导致龋齿的结构具有活髓但剩余牙齿不足的牙齿保留计划的修复材料的结构。最后，据估计，20% 至 30% 的牙齿需要根管治疗治疗有活髓，仅需要根管治疗通过利用来增强修复材料的保留根管间隙的解剖结构。基因工程材料可能具有促进牙根侧面牙本质形成的能力运河空间，而不是以其为代价，这可能会导致显着减少需要根管治疗的牙齿数量全国治疗。 OP 和骨形态发生蛋白 (BMP) 构成 TGF-B超家族；该家族的蛋白质已被证明具有多样性生物活性，包括分化、组织形态发生、再生、修复。重组人 OP-1，与一种不溶性 I 型胶原蛋白基质 (CM)，已被证明是一种有效的修复性牙本质生成的刺激剂。之前的研究非人类灵长类动物防龋牙齿的首席研究员证明暴露的牙髓组织对使用 2.5 ug 有反应每毫克 CM 的成纤维细胞和血管生成侵袭的 OP-1 材料，产生矿化的新牙髓组织，取代（并取代）OP-1/CM。此外，修复性牙本质是在表面形成的（而不是以牺牲牙本质为代价））现有牙髓组织，以及修复性牙本质的量形成的比例与放置在 OP-1/CM 上的总质量成正比。暴露的纸浆。最终修复牙本质的矿化率为95% 6个月内完成。 OP-1/CM 材料显然提供了再生缺失牙齿的牙本质成分的潜力结构，而不是用修复性牙科材料代替。然而，迄今为止的所有研究都集中在具有以下特征的非龋齿上：正常的牙髓结构和活力。该提案的具体目标是 1) 优化条件诱发狒狒牙齿冠牙髓炎； 2）表征炎症反应，3) 优化浓度 OP-1/单位质量的 CM 用于诱导修复性牙本质发生根髓组织深入到发炎的冠牙髓。具体目标 1 和 2：试点实验将测试将不同浓度的 LPS 置于暴露和截肢的牙齿上牙髓，诱发牙髓炎。具体目标 3：四只动物将为人类提供总共 65 颗牙齿评估 OP-1/CM 对“感染”牙髓组织的反应。诱发牙髓炎后，牙齿将重新张开，手术部位机械清洗并用无菌生理盐水冲洗，进入牙髓腔的通道扩大，所有冠牙髓组织用牙科旋转器械去除。 OP-1/CM浓度为2.5， 7.5和25微克/毫克将被放置在暴露的根组织上。对照组包括将 2.5 ug/mg OP-1/CM 对照置于“假手术组”中。感染的牙齿，并单独放置 CM。所有牙齿都会恢复含有玻璃离聚物基料、清漆和汞合金。组织样本将 4周后收集。传统组织学（H&E、Masson's Trichrome 和 von Kossa's），组织形态计量学和免疫组织化学将使用规定的技术。所有实验预计将结束 6-7个月内。