Saudi Endodontic Journal (Jan 2011)
Apical Patency or Apical Plug: A Literature Review
Abstract
The aim of this work was to undertake a literature review on two different techniques of apical preparation of root canals e.g. apical patency and apical plug. Apical patency is a technique in which apical constriction and apical foramen are kept patent throughout the instrumentation of root canals. This technique prevents packing of debris at the apical area. It also helps to maintain working length. A small patent file 1mm longer than the working length is passed through the apical foramen passively. This technique is thought to ensure complete debridement of root canals. It is associated with less postoperative pain. The objections to this technique are the extrusion of debris, irrigating solutions, sealer and filling materials. It may also cause over instrumentation and foramen transportation. Enlargement of apical constriction or apical foramen through patency files is not supported by literature. Apical plug is the technique in which instrumentation is kept within working length of the root canals without using any patency file. This results in the formation of an apical plug composed of dentinal chips in the apical third of the root canal. Apical plug may be contaminated with micro flora and necrotic tissues leading to inflammatory reactions in the periapical tissues. This technique prevents the extrusion of debris, irrigating solution, sealers and thermoplastic gutta-percha. However, intentional packing with dentinal chips or biological compatible materials at the apical area is required in teeth with immature apices, root resorption, or when apical constriction is violated due to over instrumentation.