title: Variables affecting electronic root canal measurement.
abstract: This study was conducted in two parts. In the first part, 20 single-rooted teeth that had been scheduled for extraction were investigated. The electronic root canal lengths were measured in vivo with a Dental Sono-Explorer type Y-III, and the actual canal lengths were measured after extraction of the teeth. The rate of agreement of the two measurements was 77.5% within a range of +/- 0.5 mm, while it was 100% at +/- 2.0 mm, which is acceptable clinically. In the second part, there were 19 simulated canals whose lengths and apical foramen sizes were known beforehand. Experiments revealed a negative correlation between the areas of the apical foramina and the difference between the electronic and the actual root canal lengths. This relationship was shown by the linear regression equation: ŷ = 0.6-1.6x. With the exception of the smallest areas of foramina, electronic root canal length measurements were less than the actual lengths.
authors.affiliation: Fourth Military Medical University, Xian, China.
authors.forename: Y N
authors.initials: YN
authors.lastname: Wu
authors.forename: J N
authors.initials: JN
authors.lastname: Shi
authors.forename: L Z
authors.initials: LZ
authors.lastname: Huang
authors.forename: Y Y
authors.initials: YY
authors.lastname: Xu
mesh_terms: D000704:Analysis of Variance; D003786:Dental Pulp Cavity / Q000033:anatomy & histology*; D004582:Electronics, Medical; D006801:Humans; D009811:Odontometry / Q000295:instrumentation*; D012390:Root Canal Therapy / Q000295:instrumentation*; D014092:Tooth Root / Q000033:anatomy & histology