4) Mattews, B., Searle, B. N., Adams, D. and Linden, R.: Thresholds of vital and non vital teeth to stimulation with electric pulp testers, Brit. Dent. J., 137: 357-355, 1974.
5) Reynolds, R. L.: The determi nation of pulp vitality by means of thermal and electrical stimuli, Oral Surg., 22: 231-240, 1966.