Past the age of two, dummies can begin to disrupt the alignment of secondary teeth. So experts advise against prolonged use. Also, studies have found that introducing dummies too early may interfere with breast-feeding. But dummies are not all bad.

Recent research has linked dummies to a reduced risk of sudden infant death syndrome (SIDS). Dr Soxman lists the pros and cons of dummies in the current issue of the Journal of General Dentistry. Several studies have linked dummy use before the age of one year to a lower risk of SIDS, which is most common between two and four months and in response to this the American Academy of Pediatrics recently released a statement recommending the use of pacifiers at naptime and bedtime through the first year of life (though not until after one month of age in breastfeeding infants).

Some research suggests that infants who sleep with a dummy sleep less deeply and may be roused more easily if their breathing stops. Also, studies have found that a dummy during painful procedures, like a vaccination shot, can ease a child's distress.

So the pros of dummies, Dr Soxman writes, "appear not only to justify their continued use in infants and toddlers but to support it."

However, many breastfeeding organisations dispute the claim that dummies are helpful to a baby. They would point out that frequent nighttime breastfeeding has the same effect of producing lighter sleep in a baby. They also argue that a baby gets far more in the way of comfort from sucking on its mother's breast than it does sucking on a dummy.

Dummies are a contentious issue with entrenched camps on both sides. However, if you do allow your child to suck on a dummy you should be aware of the right and wrong ways of using a dummy.

First, experts, like the American Academy of Pediatrics, suggest waiting until your baby has been breast-feeding for at least a month before trying a dummy. Breastfeeding is cruscial at this stage with both mother and child learning how tobreastfeed. Waiting a while may cut the chances of interfering with successful breast-feeding.

So, when should you wean your child off the dummy?

Dr Luke Matranga, a past president of the Academy of General Dentistry and an associate professor at Creighton University School of Dentistry in Omaha, Nebraska recommends "The age of 2 is a good guideline". He goes on to say that problems with baby teeth or underlying bones could still correct themselves when a child stopped using a dummy by age two or three.

Also, the use of dummies may be preferable to thumb-sucking, which can do more damage to the dental structures and is a harder habit to break, according to Dr Matranga. Thumb sucking doesn't cause tooth decay. Tooth decay is caused by bacteria, not sucking.

Ideally, dummies should be used only when an infant is falling asleep, instead of all day long.

To reduce chances of choking, parents should stop the use of dummies when they show signs of deterioration in the nipple, and choose dummies with ventilation holes in the shield. Finally, clean you baby's dummy after use: wash in soap and water and never put the pacifier in your own mouth to clean it.