Variation in phosphoric acid concentration and treatment time and HEMA diffusion through dentin.

Abstract

HEMA was detected in the pulp chambers of all teeth from 4.32 minutes after resin placement. Mean total (cumulative) release at 10 days for all groups was in the 2-4 mumol range. The highest HEMA diffusion rate was 4.32 minutes after placement and were in the range 6-13 times greater than control in the 10%-15 seconds, 10%-30 seconds, 10%-60 seconds, 37%-15 seconds, and 37%-30 seconds groups. Unexpectedly, by far the lowest early rate at 4.32 minutes was in the 37%-60 seconds group (0.6 times of no-acid control).