Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, PR China.
Department of Endodontics, The Dental College of Georgia, Augusta University, Georgia, USA.
Sci Rep. 2017 May 8;7(1):1582. doi: 10.1038/s41598-017-01697-1.
Sodium hypochlorite is an effective irrigant for chemical debridement of root canals. However, increasing the intracanal pressure during irrigant delivery may result in irrigant extrusion into the bone and soft tissues surrounding the tooth. Because clinicians often encounter teeth with intracanal communications, the objective of the present study was to examine the effects of canal anastomosis on the generation of periapical fluid pressure at different fluid flow rates and insertion depths. Two similar polycarbonate models were used to simulate a single root with double canals, one containing, and the other without communicating channels between the canals. For both models, periapical pressure increased with increasing irrigant flow rates and insertion depths of a 30-gauge side-venting needle. In the presence of communicating channels, the magnitude of pressure build-up decreased by almost 90% irrespective of the fluid flow rate or needle insertion depth. Pressure reduction in anastomoses-containing roots provides an explanation why pressure generation in single roots is considerably higher. Nevertheless, it is still possible in teeth with canal anastomoses for pressure exceeding the intraosseous pressure to be generated when the fluid flow rate is sufficiently high and when the needle tip is close to the apical terminus.
次氯酸钠是根管化学清创的有效冲洗剂。然而，在冲洗剂输送过程中增加根管内压力可能导致冲洗剂挤出到牙齿周围的骨和软组织中。由于临床医生经常遇到有根管交通的牙齿，本研究的目的是检查在不同冲洗流速和插入深度下根管吻合对根尖周液压力产生的影响。使用两个类似的聚碳酸酯模型模拟一个具有双根管的单个牙根，一个含有，另一个没有根管之间的连通通道。对于这两种模型，随着 30 号侧孔针头冲洗流速和插入深度的增加，根尖周压力也随之增加。在存在连通通道的情况下，压力积聚的幅度几乎降低了 90%，而与冲洗流速或针头插入深度无关。吻合根中的压力降低解释了为什么单根中的压力产生要高得多。然而，当流速足够高且针头尖端接近根尖末端时，即使在存在根管吻合的牙齿中，也有可能产生超过骨内压的压力。
