Sound stimulation and its effect on dental sensation threshold.

The success of "auditory analgesia" in dental operations may be a result of distraction, suggestion, or cross-sensory masking, or of a combination of the three. An attempt to separate these influences was made by measuring the change in sensitivity to electrical stimulation of the teeth in typical dental patients upon presentation of loud white noise. No differences in this "tingle" threshold under noise and no-noise conditions were found, either when preliminary instructions were neutral or after implicit or explicit suggestion that the noise would raise the threshold. These results indicate that auditory analgesia is probably not an example of cross-sensory masking, and that its successful use in the clinical situation depends both on distraction and on suggestion.