An open bite is a condition presenting as a gap between the upper and lower anterior teeth while the back teeth are in contact. In a normal bite the lower anterior teeth should be tucked slightly underneath the upper anterior teeth and be in contact. This condition can interfere with speech, specifically production of certain sounds. It can also make it difficult to bite certain foods since the upper and lower incisors are not in contact. Prolonged thumb or pacifier sucking usually causes an open bite. The condition is treated with comprehensive orthodontic treatment. In extreme cases, jaw surgery might be recommended.