Oral habits such as digit sucking can be normal for infants and toddlers. This tendency for sucking should diminish by age 3. After age 5 it becomes a habit.   Long-term sucking habits can interfere with optimal orofacial growth and development.  
Many times, after a long-term sucking habit has been eliminated, the muscular and swallowing problems remain.  This is because the oral muscles, tongue, teeth and jaws have formed and learned to function with the thumb, finger or pacifier in the mouth.  Certified orofacial myofunctional therapists provide guidance, support and a positive approach for digit sucking elimination and other non-nutritive habits such as pacifiers.