In infancy and very early childhood, these sucking habits are normal and many children stop these habits on their own; however, if they continue past 4-5 years of age, the prolonged sucking habits can interfere with normal skeletal and muscle development of the oral, facial and nasal areas. The palate can grow vertically and narrow, resulting in a vaulted shape from the pressure of the thumb, and can affect the development of the sinus and nasal cavity. Tooth eruption and alignment, swallowing, breathing and speech patterns can also be negatively affected.  

Sucking habits will usually need to be eliminated before orthodontic treatment. Eliminating a chronic sucking habit with positive reinforcement and behavior modification proves beneficial in other aspects of a child's well-being, as well. Children can experience an improved appearance, better dental health and speech, as well as increased self-confidence.

A primary goal of orofacial myofunctional therapy is to establish a lips-closed posture with nasal breathing and the tongue resting up on the palate. This posture establishes a healthy orofacial muscular environment that encourages the normal process of dental eruption and facial development.