ASSOCIATION OF INCISOR PROTRUSION WITH DIGIT SUCKING AND ALLERGIC NASAL ITCHING

Children rub their noses to relieve the itching of allergic rhinitis. The associated itching of the palate may be relieved by rubbing or by sucking a digit. Digit sucking is said to be a cause of incisor protrusion (excess overjet). A team comprised of a pediatrie allergist, an otolaryngologist, a technician, and an interviewer studied 354 Vancouver primary school children. One year later their mothers were requestioned by another interviewer. There was no increase in the prevalence of incisor protrusion in children with a stuffed nose or with enlarged adenoids. Digit sucking on its own doubled the prevalence of protrusion. When, in addition to digit sucking there was evidence of allergic itching, the prevalence of protrusion was increased about five times (statistically significant). Evidence of allergic itching alone did not increase its prevalence. Digit sucking is clearly related to incisor protrusion. It is postulated that allergic palatal itching is a stimulus for increased digit sucking in children with this habit, resulting in more incisor protrusion. © 1969.