Effect of pepsin on erosive tissue loss and the efficacy of fluoridation measures in dentine in vitro

Abstract

Objectives. In dentine, erosive lesion progression and efficacy of fluoridation measures for symptomatic therapy of dental erosion are both dependent on the presence of the organic matrix. In patients with eating disorders in combination with chronic vomiting, the demineralized organic matrix can be degraded by gastric enzymes. The aim of this study was to investigate the effect of pepsin on erosion progression and the efficacy of fluoride in dentine. Material and methods. Human dentine specimens were prepared and randomly divided into 4 groups of 20 specimens each. They were subjected to a cyclic de- and remineralization procedure for 9 days. For demineralization (6×2 min per day), an HCl solution (pH 1.6) was used in all groups. In two groups, pepsin (1.5 mg mL⁻¹) was added to the demineralization solution. Fluoridation was performed in two groups 6×1 min per day with a mouth rinse (Olaflur/SnF₂; 250 ppm F⁻) after demineralization with both the HCl solution and the pepsin containing solution. Degradation of collagen was quantified by analyzing hydroxyproline and tissue loss was determined microradiographically. SEM images were taken in addition. Results. In the pepsin group, 1.72 (0.26) µg mL⁻¹ (mean (SD)) hydroxyproline per day was detected, and in the pepsin-fluoride group 1.95 (0.50) µg mL⁻¹. Tissue loss after 9 days in the control group was similar to that in the pepsin group (122.2 (53.4) µm and 122.2 (38.0) µm, n.s., respectively). Fluoridation reduced tissue loss after demineralization (98.8 (30.2) µm) but not after pepsin treatment (125.2 (34.2) µm; p≤0.05). Conclusion. Under the conditions used, pepsin had no influence on tissue loss, but altered the efficacy of fluoridation measures.