Varghese R, Jose A, Singh ML, Magnuson B, Farag A, Kafasis N, Tzavaras E and Papas A
Title: Sensory perception of an experimental mouthwash for dry mouth symptoms: two randomized clinical studies. Background: A dry mouth accompanied by salivary hypofunction can negatively affect mastication, deglutition and speaking and can contribute to dental erosion, caries, halitosis and periodontitis. Oral mucosal surfaces consequently become desiccated, friable, and more susceptible to abrasion so it’s essential that any treatment used by a person with dry mouth is gentle on the oral mucosa. Here, two randomized, examiner-blind studies utilized questionnaires to assess sensory perception of an experimental mouthwash in participants experiencing dry mouth, some with Sjögren’s syndrome (SS), in comparison to water. Methods and findings: In Study 1 (single-dose, crossover), participants rinsed with 15 mL mouthwash or water for 30-seconds. The primary efficacy variable was post-product use response to ‘This product is gentle’ (five-item Likert scale). In Study 2 (8-day, parallel-group), participants rinsed 1–2x/day at home with 15 mL mouthwash for 30 seconds or used water as required. Supervised administration (15 mL of assigned product for 30 seconds) was carried out on Days 1, 3, and 8, followed by completion of a four-question sensory questionnaire (secondary variables). In Study 1 (n=55), most participants agreed/strongly agreed that mouthwash (78.2%) and water (89.1%) were gentle (similar results for SS/non- SS participants). In Study 2 (n=100), at Day 8 there were no between-treatment differences in overall likability or flavor pleasantness. Significant differences were found in favor of the mouthwash for freshness (0.89[95% CI 0.46, 1.33]) and in favor of water for gentleness (-0.57[-1.03, -0.11]). There were no treatmentrelated adverse events in Study 1 and eight mild-moderate adverse events with the mouthwash in Study 2. Conclusions: Participants with dry mouth with/without SS perceived likability and flavor pleasantness of the experimental mouthwash to be similar to water, with differences in perceived freshness and gentleness. This mouthwash may therefore be suitable for use by people experiencing dry mouth.