Title: 0729 - Remote Noxious Stimuli Enhances Odontogenic Pain Localisation


Nuha Ashaibi (Presenter)
School of Dentistry, University of Dundee

Andrew Mason, School of Dentistry, University of Dundee
Mark Hector, School of Dentistry, University of Dundee
Pauline Maillou, School of Dentistry, University of Dundee


Objectives: Patients often have difficulty localising pain of dentinal or pulpal origin to a specific tooth. This can make it difficult for the dentist to make an accurate diagnosis and thus manage the pain effectively. This study aimed to determine how accurately human volunteers could locate electrically evoked odontogenic pain under controlled experimental conditions and to determine the effect that the application of a concurrent remote noxious conditioning stimulus (RNCS) had on this ability.

Methods: Experiments were performed on 17 healthy (6 male and 11 female, aged 20-32years) consenting volunteers. Custom made bipolar electrodes were attached to the labial surfaces of the right maxillary central and lateral incisors and canine teeth. Single, 1ms, electrical stimuli (intensity: 1.25x pain threshold) were delivered to each tooth at 1 minute intervals. Stimulus parameter monitoring was used to monitor stability of the electrodes. Each tooth was stimulated 3 times in total, in a random order using a counterbalancing scheme. The volunteers were asked to identify the stimulated tooth. This was the control phase. The experiment was repeated with the volunteer receiving a RNCS (immersion of the ipsilateral hand in 3°C water for 10s). Accuracy of stimulus localisation for both conditions was expressed as a percentage success.

Results: The overall accuracy of pain localisation was 33% under control conditions. This increased significantly to 60% with a RNCS (P〈0.0008, Wilcoxon Signed Ranks Test). Interestingly, there were differences in localisation accuracy between the three teeth under RNCS conditions (P〈0.001 Friedman’s 2-Way ANOVA). The accuracy of localising pain from the central incisor being greater than from the canine (P〈0.003).

Conclusions: The application of a RNCS improved the ability to localise the tooth stimulus in anterior teeth. This may be due to activation of Diffuse Noxious Inhibitory Control (DNIC) mechanisms.

Student Presenter

Disclosure Statement:
The submitter must disclose the names of the organizations with which any author have a relationship, the nature of the relationship, and the clinical or research area involved. The following is submitted: NONE