Ability of healthy and inflamed human dental pulp to reduce hydrogen peroxide

This study examined the defensive ability of human dental pulp against H2O2 in healthy and reversible and irreversible pulpitis tissues through determination of catalase activity by spectrophotometric methods. Thirty-five systemically healthy patients were donors of the pulp tissue, and pulp conditions were assessed using clinical and X-ray evaluations. Catalase activity was 1.61 +/- 0.23 U mg(-1) protein in the healthy tissues, 2.99 +/- 0.45 U mg(-1) protein in the reversible pulpitis tissues, and 2.44 +/- 467 mU mg(-1) protein in the irreversible pulpitis tissues. All differences between the groups were statistically significant. These results point to a role for catalase during dental pulp inflammation in humans, and therefore demonstrate an inherent biological defense system against reactive oxidants in human dental pulp.