Study on the accuracy of Raypex-5 root apex locator

【Objective】To investigate the accuracy of working length determined by Raypex-5 root canal apex locator.【Methods】The root canal length of 96 root canal in 73 teeth was measured by Raypex-5 apex locator.The patient were divided into three groups.The root canals were prepared based on the length detected and X-ray films taken.The actual length was calculated and the accuracy was obtained.【Results】The accurate location within ±0.5 mm from the apical foramen was obtained in 97.26% of the canals.The significant difference between the pulpitis(100%)and the apical periodontitis(95.35%) was not found(P0.05).The significant difference between vital(100%) and necrotic canals(90.91%) was not found(P0.05)either.【Conclusions】Raypex-5 root canal apex locator is a reliable device in the determination of the working length of root canal and reduce the exposure to x-ray.