The Effect of Coronal Pre-flaring and Root Canal Irrigant on Apex Locators Accuracy: In-Vitro Study.

Successful root canal treatment is influenced by the apical extent of root canal preparation and the eventual root canal filling. Achieving the full working length until the apical constriction which is usually 0.5 – 1 mm shorter than the anatomical apex is crucial. Electronic apex locators were used to detect the working length more accurately. There are six generations of electronic apex locators in the market. The selection of the appropriate irrigation with each apex locator for accurate working length determination is not fully investigated. The actual working lengths of 120 freshly extracted human single-rooted teethTh were measured and compared with their working lengths using 3rd generation (Root ZX) followed by 6th generation (Raypex 6) apex locators in dry medium, presence of 5.25% sodium hypochlorite, and 2% chlorhexidine, without coronal pre-flaring and after coronal pre-flaring using the same irrigating media. Data were collected, tabulated and afterwards analysed using one-way ANOVA with post-hoc to evaluate the significant difference in average WL between actual WL, Root ZX, and Raypex 6 apex locator working length accuracy. Results revealed that the significant results were shown in roots that were coronally pre-flared and their working lengths were measured in a dry medium using Raypex 6 apex locator. While using the Root ZX apex locator, the most accurate results were shown in roots that were coronally pre-flared and their working lengths were measured while using chlorhexidine irrigating solution.