A procedure involving music and noise has been effective in suppressing pain in 5000 dental operations. The music promotes relaxation, and the noise (the main agent) directly suppresses pain. The dental procedure and results are described, and an explanatory hypothesis is suggested.

No abstract

The observations to be reported were made in a dentist's chair. Part of the sensory stimulation was generated by the dentist and his dental equipment, particulary his drill, during the course of routine dental operations. Part was generated by apparatus consisting of random noise generator, low-pass filter, stereophonic tape playback, patient-operated faders and attenuators, power amplifiers, and earphones. The initial observations concerned masking of the drilling noise. Low-pass random noise sufficiently intense to mask the drilling noise completely turned out not to be itself objectionable. Not only the sound of the drill, but also much of the massive complex of tension, anxiety, and pain was drowned in the masking noise. One patient {JCRL) made subjective observations, during a single drilling, alternately with and without the masking noise. During the masking noise, there was only a “small, thin sensation of pain.” When the masking noise was off, the noise and vibration of the drill accrued to the core pain and made it seem larger and more noxious. Further tests were made with music, and with music and noise in combination. Music is less effective than noise as a masker, but it is very effective in inducing relaxation. The combination of music and noise, alternating under the patient's control, appears to provide a practicable dental analgesia. Observations on more than 170 patients will be described, and applications outside the field of dentistry will be mentioned.

No abstract

The procedure described at the Fall Meeting—the procedure in which music and noise under the control of the dental patient are used to mask the sound of the dental drill and the pain produced by drilling or extraction—has now been employed on over 500 patients with approximately 90% success. It is now considered definite on the basis of more than 50 extractions (in which the drill did not enter the picture) that the masking noise actually masks pain. The device used to present the acoustic signals to the patient (“Audio Analgesiac”) has been considerably improved, and it is now being used on an experimental basis by several dentists, whose reports are beginning to come in. The use of noise signals more pleasing to the ear than filtered random noise is being explored. The experience to date will be summarized and preferred music and noise signals will be demonstrated.