PURPOSE: The purpose of this study was to evaluate the accuracy of the Root ZX electronic apex locator in determining canal length in primary incisors. METHODS: Root ZX was utilized to measure the canal lengths of 150 primary incisors in vivo. After the teeth were extracted, a standard ruler was used to measure the canal lengths to the nearest 0.5 mm. A paired t test was used to compare the lengths obtained in vivo with Root ZX and the lengths measured in vitro. RESULTS: In 98 (65%) of the canals, the length measured by Root ZX was determined to be equal to the length measured in vitro. Root ZX measurements were found to be less than in vitro measurements by 0.5 mm in 24 canals (16%), and were greater than in vitro measurements by 0.5 mm in 21 canals (14%). Root ZX measurements exceeded in vitro measurements by 1.0 to 1.5 mm in 5 canals (3%) and were less than in vitro measurements by 1.0 mm in 2 canals (1%). Paired t test analysis indicated no significant difference between the 2 measurement methods (P=.67). CONCLUSIONS: Root ZX can accurately assess the length of canals in primary incisors.
PURPOSE: The purpose of this study was to evaluate the accuracy of the Root ZX electronic apex locator in determining canal length in primary incisors. METHODS: Root ZX was utilized to measure the canal lengths of 150 primary incisors in vivo. After the teeth were extracted, a standard ruler was used to measure the canal lengths to the nearest 0.5 mm. A paired t test was used to compare the lengths obtained in vivo with Root ZX and the lengths measured in vitro. RESULTS: In 98 (65%) of the canals, the length measured by Root ZX was determined to be equal to the length measured in vitro. Root ZX measurements were found to be less than in vitro measurements by 0.5 mm in 24 canals (16%), and were greater than in vitro measurements by 0.5 mm in 21 canals (14%). Root ZX measurements exceeded in vitro measurements by 1.0 to 1.5 mm in 5 canals (3%) and were less than in vitro measurements by 1.0 mm in 2 canals (1%). Paired t test analysis indicated no significant difference between the 2 measurement methods (P=.67). CONCLUSIONS: Root ZX can accurately assess the length of canals in primary incisors.