A Novel Instrument to Determine Pulp Proximity

Abstract - The aim was to determine whether extracted teeth could be used to test the PrepometerTM instrument, which indicates pulp proximity with green/amber/red light emitting diodes. Third molars were reduced to a plane in dentine and PrepometerTM readings made. Dentine was removed in 0.5 mm increments and readings made until only lights 9 or 10 (red) showed. The teeth were sectioned and the dentine thickness measured. Analysis permitted construction of a highly significant predictor-model (p < 0.01), the red/amber light boundary coinciding with a dentine thickness of 2.4 mm. The PrepometerTM was consistent in predicting pulp proximity but was more sensitive than specified.

KEY WORDS: Pulp proximity; tooth preparation; alternating current; instrument; LED display