The influence of triclosan, zinc or propylene glycol on oral mucosa exposed to sodium lauryl sulphate

Previous studies on triclosan treatment of skin exposed to sodium lauryl sulphate (SLS) indicated a protective rôle of zinc and an irritant effect of propylene glycol (PG). The aim was hence to examine whether zinc or PG also may affect SLS-induced oral mucosal reactions, and also to test the influence of zinc in combination with triclosan. 15 healthy dental students participated in this double-blind crossover study performed in 2 experimental series. They were rinsing 2x daily with solutions containing (A) 1.5% SLS, (B) 1.5% SLS/0.5% zinc citrate and (C) 1.5% SLS/PG (1:8) in experiment 1, and (D) 1.5% SLS/0.15% triclosan/0.3% zinc citrate and (E) 1.5% SLS/0.15% triclosan in experiment 2. Clinical evaluation by 2 examiners of degree of erythema and oral mucosal desquamations was then performed. The critical micellar concentration was also determined. SLS and SLS/PG, which were not different in effect, evoked significantly more erythematous reactions than SLS/Tri/Zn. This solution was numerically but not statistically better than SLS/Tri, and the latter also did lead to significantly less erythema than SLS/PG. In conclusion, the present study revealed no irritation of the oral mucosa due to PG, whereas a protective effect of zinc as well as the anti-inflammatory effect of triclosan were confirmed.