Sodium lauryl sulfate (SLS) is the most commonly used detergent in dentifrices. The present study was concerned with the effect of SLS content of toothpastes on oral epithelial desquamation in an experimental model. Ten dental hygiene students participated in this double-blind cross-over study. Five dentifrices with different concentrations of SLS (ranging from 0.0% to 1.5%) were used in randomized order in the study. One centimeter of each test dentifrice was applied in a cap-splint, which covered both attached and non-attached oral mucosa of the upper jaw for 2 min twice daily. The test period for each experimental dentifrice was 4 days, followed by a 10-day rest period. The dentifrice without SLS did not result in any onward reaction, whereas the dentifrice containing 1.5% SLS provoked desquamation in 60% of the subjects.