The aim of this study was to determine the clinical efficacy of a dental chew with mechanical and chemical properties in 2 toy dog breeds. Eight Yorkshire terriers and 9 Chihuahuas participated in a crossover design trial. Gingivitis, dental plaque, calculus, and volatile sulfur compounds (VSC) in the breath were assessed after 4 weeks and 9 weeks, respectively. When dogs were fed 1 dental chew per day they had significantly reduced gingivitis (-20%, P < .001), accumulation of plaque (-15%, P < .001), calculus (-35%, P = .001), and VSC concentration (-19%, P < .001) compared to when receiving no chew. A significant breed effect was observed on all the average dental indices and VSC concentration.