Tooth pulp pain is considered an excellent model for human pain studies and algesimetry because experimentally induced pain simulates clinical pain. Ozick's techhique of electrical stimulation of the tooth pulp will be modified into a psychophysical method for measuring pain threshold, pain tolerance, pain sensitivity range and drug request point. The modified technique will be evaluated for its usefulness and sensitivity in human analgesic assays with mild and moderately potent oral analgesics. Pain response parameters measured with the tooth pulp stimulation method will be correlated with those obtained from six other standardized laboratory pain-inducing methods. All correlations, together with correlations obtained from two personality questionnaries, will be placed in a correlation matrix and factor analyzed. Search will be made for a specific pain factor similar to the pain endurance factor previously isolated by Wolff. On the basis of such correlations and factor analyzed data, a short, objective, valid and reliable pain measurement battery will be constructed. Finally, traditional psychophysical methodology will be compared and contrasted to signal detection techniques in the field of pain, using tooth pulp pain as the experimental model. Paid, healthy, adult human volunteers will be used in all studies.