INCREASED HUMAN GINGIVAL BLOOD-FLOW INDUCED BY SODIUM LAURYL SULFATE

Laser Doppler flowmetry was used in 14 subjects to investigate the eff ect of sodium lauryl sulfate (SLS) on gingival microcirculation. SLS, the most widely used detergent in toothpastes, exhibits a denaturing p roperty, increases oral mucosal permeability and may cause epithelial desquamation of oral soft tissues. Gingival blood flow (GBF) was measu red bilaterally 3 mm above the gingival margin, between the central an d lateral maxillary incisors, before and after application of 1.5% SLS for 90 s to the gingiva on one side. The contralateral side served as a control with water application only. Relative changes in GBF were m easured for 15 min on both sides. SLS increased the median GBF signifi cantly between the 2nd and 10th min with a peak at 8 min, whereafter t he how decreased towards baseline. On the contralateral side, GBF init ially declined before returning to baseline. 10 subjects felt a burnin g pain from the gingiva after SLS application and GBF increased in all of them. SLS increased the relative gingival blood flow presumably du e to its penetrating and irritative properties, which resulted in vaso dilatation. Laser Doppler flowmetry may be a useful non-invasive metho d for intraoral testing of different agents meant for oral use.