Sir, J. Hartley, in a letter published in BDJ volume 217 no. 5, asks 'where this new advice, “Spit don't rinse”, is coming from'.

In their paper, The influence of toothbrushing and post-brushing rinsing on caries experience in a caries clinical trial (Community Dent Oral Epidemiol 1998; 26: 406–411), Chestnutt I G, Schafer F, Jacobson A P and Stephen K W reported the beneficial effect on caries increment of spitting rather than rinsing after toothbrushing with a fluoride toothpaste. These authors recommended that the 'spit don't rinse' message should be integral to post-brushing oral hygiene instructions.

1. Dalbeattie