The Localization Accuracy of Electrically Evoked Dental Sensations

Abstract

Objectives: 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.

Materials and methods: 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.

Results: 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).

Conclusions: 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.

Keywords: dental; localization; pain.

Figure 1

This figure shows the different colors of heat shrinkage for each electrode, from left to right: 13, 11, 21, and 22.

Figure 2

Experimental setup: Five customized tooth electrodes are attached to the teeth—three test teeth (green) and two control teeth (blue). They are connected to the switch box, which is connected to the DS7 stimulator.

Figure 3

Experimental teeth: Green teeth are test teeth and blue teeth are control teeth. Session 1: Incisor test teeth and control teeth. Session 2: Teeth posterior to the incisor teeth are test teeth (L/R) and anterior teeth are control teeth.

Figure 4

A box and whisker plot illustrating the percentage success rate for the pooled data for each tooth.

Figure 5

Box and whisker plot representing the median success rate for incisor teeth and teeth posterior to the incisor teeth at both intensities for all volunteers. Green: anterior teeth; orange: right post‐incisor teeth; blue: left post‐incisor teeth. Anterior = incisor teeth at T and 1.25T; L post = left post‐incisor teeth at T and 1.25T; R posterior = right post‐incisor teeth at T and 1.25T.

Figure 6

Box and whisker plot representing the median success rate for incisor teeth and teeth posterior to incisor teeth at the higher intensity (1.25T) for dental (D) and non‐dental (ND) volunteers.