Spectrophotometric analysis on bleaching efficacy of blood stained demineralized and deproteinized dentin--an in vitro study.

The objectives of this in vitro study, is to evaluate the influence of various dentin treatment procedures prior to bleaching namely, demineralization and demineralization in conjunction with deproteinization on the dentin permeability and bleaching efficacy. The study used a total of 40 sound premolars, which were sectioned longitudinally, and their color coefficients and absorption spectrum was recorded and used as control values for the later study. These dentin samples were then discolored by blood and their color coefficients and absorption spectrum were calibrated. They were then divided into two Groups with 20 samples each per group. Group A--dentin samples were demineralized prior to bleaching. Group B--dentin samples were deproteinized also in conjunction to demineralization prior to bleaching. The values of color coefficient and absorption spectrum were determined using Spectrophotometer for samples of each group respectively. There were significantly higher color coefficient and absorption spectrum values in the group where dentin was treated with demineralization in conjunction with deproteinization prior to bleaching when compared to the group where dentin was treated by demineralization alone prior to bleaching. Demineralization in conjunction with deproteinization has proven to be a good method of increasing dentin permeability for achieving a higher bleaching efficacy.