Which type of fluoride would not be used on a very young child?

For very young children, fluoride rinses are generally not recommended as they require the ability to swish and spit, which is a skill that most toddlers do not possess. Young children can easily swallow the rinse, leading to an increased risk of fluoride ingestion, which can contribute to dental fluorosis or other health issues.

On the other hand, fluoride options like gel, foam, and varnish are applied in a manner that minimizes the risk of swallowing. Gels and foams are typically applied in a controlled setting by a dental professional, while fluoride varnish is painted on the teeth and sets quickly, allowing for a much lower chance of ingestion. Thus, due to safety concerns and the developmental capabilities of very young children, rinses are not suitable for this age group.