Abstract
OBJECTIVES: To assess the retention of o-cymen-5-ol and zinc on reconstructed human gingival tissue delivered by topical applications of toothpaste formulated with 0.1%w/w o-cymen-5-ol and 0.6%w/w zinc chloride (ZnCl2). METHODS: EpiGingival tissues were treated topically for 2 minutes with either solutions or toothpaste slurries containing o-cymen-5-ol and ZnCl2. Tissues were rinsed with water between application and the effects of repeat dosing for up to 6 occasions were investigated. Tissues were blot dried, extracted and o-cymen-5-ol and zinc were measured by HPLC and atomic absorption spectroscopy, respectively. RESULTS: Retention of o-cymen-5-ol and zinc delivered from solutions to EpiGingival tissues showed a dose response to the concentration and to the number of applications. Significantly higher concentrations of zinc were delivered to EpiGingival tissues by toothpaste compared to equivalent doses delivered from solution. Equivalent doses of o-cymen-5-ol were delivered from toothpaste and solution. No cytotoxic effects on the EpiGingival tissues, measured by MTT viability, were detected following application of test toothpaste compared to a water control. CONCLUSIONS: Reconstructed human gingival tissue proved to be an effective model for the assessment of active retention from topically applied formulations. The test toothpaste was effective in delivering o-cymen-5-ol and zinc to oral soft tissue in vitro.