Ariizumi Y, Yoshida T, Murakami K, Kato S, Fukuro K, Kaneko S, Nakagawa K I, Asai Y
Department of Endodontics, Tokyo Dental College.
Shikwa Gakuho. 1990 Mar;90(3):421-8.
After treating the infected canals, we investigated to determine the influence of autogenous dentin chips accidentally applied as filling in the root apexes. Materials were 15 mandibular premolars and molars obtained from healthy, mature dogs. According to standard procedures, after pulp extirpation, canals were temporarily filled with sandarac cotton pellets and left otherwise untreated for 4 weeks. At this time, the degree of infection was ascertained. After root-canal enlargement, root canals were filled with No. 55 gutta-percha points; and a sealer (Neotriozinc Paste, AH26, or Sealapex) was applied. The animals were sacrificed at the conclusion of either a short term (2 weeks) or a long term (16 weeks), and histological studies were performed. Conclusions In short-term specimens, no formation of new hard tissue was observed at the apical dentino-cemental junction; and inflammatory changes in the periapical soft tissue were remarkable. In long-term specimens, hard-tissue formation had resulted in apical closure in 6 out of 8 instances; and periapical inflammatory changes had decreased. Relations between dentin-chip density and histopathological conditions were as follows: In most of the specimens that were evaluated as good, dentin chips were very densely applied. Insufficient numbers of dentin chips produced poor results. In other words, dense applications of dentin chips result in good prognoses. Consequently, when root-canal enlargement has been adequately performed, application of dentin chips to the apex of infected canals stimulates hard-tissue formation resulting in biological apical closure. In infected canals, however, the degree to which dentin chips are infected can be a major factor.
在处理感染根管后，我们进行了调查，以确定意外用作根尖充填材料的自体牙本质碎屑的影响。材料为从健康成年犬获取的15颗下颌前磨牙和磨牙。按照标准程序，牙髓摘除后，根管用山达脂棉捻暂时充填，其余不作处理，放置4周。此时确定感染程度。根管扩大后，用55号牙胶尖充填根管；并使用一种封闭剂（新三锌糊剂、AH26或Sealapex）。在短期（2周）或长期（16周）结束时处死动物，并进行组织学研究。结论在短期标本中，根尖牙本质-牙骨质交界处未观察到新硬组织形成；根尖周软组织的炎症变化明显。在长期标本中，8例中有6例硬组织形成导致根尖封闭；根尖周炎症变化有所减轻。牙本质碎屑密度与组织病理学状况之间的关系如下：在大多数评估为良好的标本中，牙本质碎屑应用非常密集。牙本质碎屑数量不足导致效果不佳。换句话说，密集应用牙本质碎屑可带来良好预后。因此，当根管扩大充分完成后，将牙本质碎屑应用于感染根管的根尖可刺激硬组织形成，导致生物学根尖封闭。然而，在感染根管中，牙本质碎屑的感染程度可能是一个主要因素。
