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Factors Relating to Dental Stain Formation in the Rat

A series of studies was conducted to investigate the use of the rat as an in vivo model for studies of dental stain and to identify dietary factors which influence stain formation in this model. It was determined that appreciable amounts of stain formed on the molar teeth of rats provided a synthetic diet containing lactalbumin, and the amount of stain increased throughout a four-week test period. Stain formation was also observed when rats were provided their diet by gastric intubation. Topical applications of chlorhexidine generally resulted in an increase in stain formation, as did the presence of tea in the drinking water. These studies support the use of the rat for investigations of dental stain.