[The zinc concentration in the dental plaque after zinc chloride mouth rinsing in relation to previous mouth rinsings with different pH values].

The zinc content in dental plaque after mouth rinsing with 0.2% zinc chloride solution is dependent on previous mouth rinsing with different pH value. Zinc retention is strongly reduced by rinsing with citric acid solution (pH value 1.0). Zinc retention is growing with increasing pH value when rinsing was made with sodium citrate buffer solution with increasing pH value. A rinsing with sodium citrate buffer solution (pH value 6.3) following a 0.2% zinc chloride solution leads to a drastic reduction of the zinc content. However, a chlorhexidine solution with the same pH value leaves no washing out effect.