Regular use of an effective oral rinse (0.12% chlorhexidine [CHX]) may be accompanied by tooth staining and slightly increased calculus formation. Since dentifrices containing soluble pyrophosphates are known to significantly reduce calculus formation, this study was designed to investigate whether CHX-induced staining and increased calculus may be reduced by the use of such dentifrices. The study compared stain and calculus formation in 163 subjects using a CHX oral rinse (Peridex, Procter & Gamble) according to label directions and either a pyrophosphate-containing anticalculus toothpaste (Tartar-Control Crest, 3.3% pyrophosphate) or an otherwise similar toothpaste without pyrophosphate (Regular Crest). Subjects were instructed to brush and floss ad lib and were examined after three and six months. Whole-mouth calculus occurrence was significantly reduced in the anticalculus toothpaste group at three and six months. Also, staining on the cosmetically important facial-anterior surfaces was significantly reduced at the 3-month examination. After six months the difference in facial anterior staining was still directionally favorable to the anticalculus toothpaste group but no longer statistically significant. These results indicate that routine brushing with an anticalculus toothpaste such as Tartar-Control Crest significantly reduces both facial-anterior staining and calculus occurrence in subjects using a CHX oral rinse. Whether more frequent or more thorough brushing would lead to still greater reductions remains to be investigated.