Fluoride ingestion from toothpaste: fluoride recovered from the toothbrush, the expectorate and the after-brush rinses.

Abstract

The aim of this study was to determine the effects of rinsing and spitting on fluoride ingestion from toothpaste during normal oral-hygiene procedures of younger children, and hence to make recommendations on rinsing during toothbrushing. The brushing habits of 166 Dutch and 185 Irish children between 1.5 and 3.5 years were observed during home visits. The weight of the toothpaste tube was determined before and after use. After brushing, the toothbrush and any associated expectorate and rinses, combined with any toothpaste spilled during the brushing procedures, were collected. The amounts of fluoride retained on the toothbrush and in the associated expectorate and rinses were measured. Over 90% of the Dutch children used a special toddlers' toothpaste with < or =500 ppm F. Eleven per cent of the younger (<2.5 years) Dutch children and 22% of the older children rinsed after brushing. Of the Irish children approximately 52% used a children's toothpaste containing around 500 ppm F. Of the younger Irish children 31% spat without rinsing, while another 31% rinsed during or after brushing. For the older Irish children, these percentages were 14 and 70%, respectively. On average, 22% of the fluoride dispensed on the toothbrush was retained on the brush after brushing irrespective of the rinsing and spitting behaviour of the children. The maximum ingestible amount of fluoride from toothpaste assuming no rinsing or spitting was calculated. Fluoride ingestion from toothpaste is significantly reduced by rinsing and/or spitting during toothbrushing. Recommendations that younger children use small amounts of toothpaste (< 0.5 g) and that children using toothpaste with > or = 1000 ppm F rinse their mouths after brushing continue to be valid.