Influence of pulp condition on the accuracy of an electronic foramen locator in posterior teeth: an in vivo study

Braz Oral Res. 2012 Mar-Apr;26(2):106-11.


The aim of this study was to assess, in vivo, the accuracy of the NovApex® electronic foramen locator in determining working length (WL) in vital and necrotic posterior teeth. The NovApex®was used in 144 canals: 35 teeth with vital pulps (68 canals) and 42 teeth with necrotic pulps (76 canals). WL was measured with the NovApex® locator and confirmed using the radiographic method. Differences between electronic and radiographic measurements ranging between 0.0 and 0.4 millimeters were classified as acceptable; differences equal to or greater than 0.5 millimeter were considered unacceptable. Pearson's chi-square test was used to assess the influence of pulp condition on the accuracy of NovApex®(a = 0.05). Regardless of pulp condition, differences between electronic and radiographic WL measurements were acceptable in 73.61% of the canals. No statistically significant differences in accuracy were observed when comparing vital and necrotic canals (p > 0.05). There were 38 unacceptable measurements. In none of these cases was the file tip located beyond the radiographic apex; in 32, it was located short of the NovApex® measurement. Pulp condition had no significant effect on the accuracy of NovApex®.

Publication types

  • Evaluation Study

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Chi-Square Distribution
  • Dental Instruments
  • Dental Pulp / diagnostic imaging
  • Dental Pulp / pathology*
  • Dental Pulp Cavity / anatomy & histology*
  • Dental Pulp Cavity / diagnostic imaging
  • Dental Pulp Necrosis / diagnostic imaging
  • Dental Pulp Necrosis / pathology
  • Electronics, Medical / instrumentation
  • Humans
  • Middle Aged
  • Odontometry / instrumentation
  • Organ Size
  • Radiography
  • Reproducibility of Results
  • Root Canal Preparation / instrumentation*
  • Tooth Apex / anatomy & histology*
  • Tooth Apex / diagnostic imaging
  • Young Adult