The effects of antimicrobial sprays and mouthrinses on supragingival plaque regrowth: a comparative study

Due to the side effects of chlorhexidine digluconate (CHX) mouthrinsing, a spray has been proposed as an alternative method of CHX delivery to the oral cavity. The aim of this study was to investigate the plaque inhibitory effects of CHX, cetylpyridinium chloride (CPC), and triclosan (TRN) delivered by sprays and mouthrinses.

The study was an observer-masked, randomized cross-over design balanced for carryover effects, involving 15 healthy volunteers in a 4-day plaque regrowth model. Products being tested (0.2% CHX, 0.12% CHX, 0.05% CPC, and 0.03% TRN) were used both as sprays and mouthrinses. A saline solution served as a negative control. On day 1, subjects received professional prophylaxis, suspended oral hygiene measures, and commenced using their allocated products. On day 5, subjects were scored for disclosed plaque.

CHX sprays (P<0.01) were the most effective sprays in preventing plaque regrowth, without significant differences between the two concentrations tested (P>0.05). TRN spray showed a significant inhibition of plaque regrowth in comparison to the negative control (P<0.05). CPC spray did not differ from saline spray (P>0.05). A similar trend of efficacy was detected for rinses. Although the effect on plaque regrowth observed with CHX rinses was superior to that of CHX sprays (P<0.0003), the latter did not cause side effects (P>0.2).

These findings, together with those from clinical trials, suggest that the CHX-containing sprays may represent an effective alternative to CHX rinses when mechanical oral hygiene has to be avoided in restricted areas. On the contrary, the TRN and CPC sprays showed little or no plaque inhibitory effects.