Comparison of Three Tongue Cleaners for Removing Tongue Coating

This randomised three-period crossover study compared the effectiveness of three tongue-cleaning devices - a bristled tongue brush, a plastic tongue scraper and a metal tongue scraper - in removing tongue biofilm. Thirty healthy volunteers aged 18 to 30 used each device once daily for 14 consecutive days, with 7-day washout periods between devices during which no tongue cleaning was performed. Tongue biofilm was measured objectively by Quantitative Light-induced Fluorescence-Digital (QLF-D) imaging, alongside the visual Tongue Coating Index, salivary pH, and participant-reported acceptability including gag reflex.

Inclusion Criteria: * Healthy volunteers aged 18 to 25 years * No professional dental cleaning within the previous two weeks * Willing to maintain usual toothbrushing and interdental hygiene practices throughout the study period Exclusion Criteria: * -History of significant systemic disease (e.g. diabetes mellitus, immune disorders) * Clinical salivary gland dysfunction or self-reported xerostomia * Active oral or mucosal infection (e.g. severe periodontitis, extensive caries) * Active mucosal lesions * Fixed orthodontic appliances * Conditions predisposing to severe gagging beyond normal clinical sensitivity * Use of topical or systemic antimicrobials or antibiotics within the previous month