A Clinical Evaluation of Accuracy of Root ZX Apex Locator

Objective:(i) to assess the accuracy of the Root ZX for measuring root canal length;(ii) to explore the factors which influenced the measurements of Root ZX.Methods:Fifty-two patients were selected for the study.The distance between the tip of probe file and radiographic apex was recorded when Root ZX indicated '0.5' readings.Every root canal working length was determined by Ingle method.The measurements of Root ZX under dry canal condition were compared with those under moist canal condition.Results:Root ZX was 96.2% accurate in positioning the probe 0 to 2mm short of the radiographic apex.No significant difference existed in the measurements of different age or gender.No statistical significance was found between the measurements of Root ZX under moist canal condition and radiographic ones.Conclusions:There was high accuracy of measuring root canal length with Root ZX apex locator,which wasn′t influenced by patient′s age,gender and periapical radiolucency.Normal saline in canal can improve the performance of Root ZX.