Non-Nutritive Sucking

The instinct to suck is a normal physiological behavior performed by almost all infants. When an infant/toddler performs this behavior and no nutrition is obtained it is referred to as non-nutritive sucking (NNS). Generally, non-nutritive sucking decreases with age and a majority of toddlers discontinue between 2- 4 years of age.

Infants and toddlers will commonly utilize a pacifier or one or more digits for NNS. Digit sucking has been found to cause more severe dental effects than pacifiers because of the strong pressure on the teeth and dental arches.

NNS can affect both the primary and permanent dentitions. Dental effects are minor in children under the age of three years. Dental problems that are commonly associated with prolonged NNS include:

Open bite: The upper front teeth do not overlap (vertically) the lower front teeth. Increased overjet: the upper front teeth protrude outward and sometimes beyond the upper lip

Decreased palatal width: The sagittal growth of the upper arch is inhibited or slowed

Posterior cross-bite: The primary and permanent molars in the upper arch occlude inside the lower molars.

Decreased maxillary inter-canine width: The space between the maxillary right and left canine teeth is decreased often leading to dental crowding.

Breaking the habit

Parents and children should know the dental effects of long-term sucking. Positive reinforcement is important for children who actively try to restrain from thumb, digit or pacifier sucking. A dentist should be consulted if the habit continues after eruption of the permanent dentition.


Parents will often report that their child is grinding their teeth and making an irritating noise while doing so. Bruxism is a self-limiting behavior that decreases as the child becomes older and the permanent dentition erupts. Children often experience attrition of the primary dentition and do not experience pain or discomfort. Children with neurological disorders are likely to have a bruxing habit that continues throughout their childhood and adulthood. If a child or young adult experiences attrition of the permanent dentition resulting from bruxism the dentist should be consulted regarding the possible fabrication of an occlusal guard.