Children should not suck on a pacifier past two.
Parents have been advised that letting their children use pacifiers after the age of two could have a detrimental effect on the development of their teeth. 
Tod Bigelow wrote in a blog for Hattiesburg American that a study carried out by the American Dental Association has shown that sucking on a pacifier can be a problem behaviour as children get older, as it can lead to a narrowing of the upper jaw in relation to the lower jaw, resulting in an improper bite.
He noted: “The study reveals that children who continue past age two increase the risk of developing protruding front teeth.”
Elsewhere, My West Texas recently reported that February is National Children’s Dental Health Month in the US and as a result, parents are being urge to ensure their children eat less sugar in order to boost oral health.
Dental professional at Casa de Amigos Fran Billingsley noted eating excessive amounts of sugar can be detrimental to a child’s oral health. She also urged parents to make regular appointments for check-ups.