The Localization Accuracy of Electrically Evoked Dental Sensations

Dental pain of odontogenic origin can be difficult to accurately locate to a specific tooth. This study aimed to determine how effectively volunteers could locate electrical stimuli applied to teeth in both the anterior and posterior regions of the upper arch.

This study was approved by the University of Dundee Research Ethics Committee (No. UREC15068). Experiments were performed on 19 healthy consenting volunteers (2 male and 17 female). Customized tooth electrodes were temporarily attached to five teeth, allowing single 1-ms electrical stimuli at two intensities (pain threshold [T] and suprathreshold [1.25T]) to be delivered randomly to any one of three teeth (three test teeth and two controls). Volunteers were asked to indicate the location of the stimulus by pointing with their fingers. This was repeated 18 times (nine times with two different stimulus intensities) in a random order using a counterbalancing scheme. Three sessions were required to include all test teeth.

The overall accuracy of localization anteriorly was 67% at intensity T and 66% at 1.25T. For the right and left posterior teeth, the accuracy was 55% and 47% at T and 44% and 42% at 1.25T, respectively. No statistically significant differences were detected at T (p = 0.35, Bonferroni-corrected Mann-Whitney U test, α = 0.01) and at 1.25T (p = 0.28, Bonferroni-corrected Mann-Whitney U test, α = 0.01).

Odontogenic pain was poorly localized even under highly controlled experimental conditions. Pain in posterior teeth may be more difficult to correctly locate compared to anterior teeth, particularly at higher intensities.