Selective stimulation of human tooth-pulp with a new stable method: responses and validation

Abstract

Introduction: The aims of this study were to establish a safe technique for selective stimulation of nerves in human tooth-pulp during long experiments and to validate its use even with stimuli of high intensities.

Methods: A custom-made veneer containing 2 silver wire-conductive cream electrodes was attached with cement to the labial surface of an upper central incisor tooth. A variety of stimulus intensities were applied, and sensory and reflex responses from jaw-closing muscles were recorded.

Results: In 15 participants, the stimuli evoked predominantly sharp or painful sensations and reflex inhibitions of activity in the jaw muscles. Stimulation of 3 non-vital teeth evoked no sensations or reflexes, even at intensities that evoked maximal reflexes in vital teeth. The electrodes had reasonably stable resistances throughout experiments lasting up to 90 min.

Conclusion: The method described enables responses to low- or high-intensity stimulation of human pulpal nerves to be investigated in long experiments.

Keywords: dental pulp; human; masticatory muscles; nociception; reflex.