Sucking on a thumb or finger is relatively common in young children but usually disappears after 4 years of age.
Physical complications of prolonged digit sucking:
(1) anterior openbite with overjet (as one or more upper teeth are pulled forward and lower incisors are pushed backward)
(2) other forms of dental malocclusion
(3) chronic paronychia on the finger(s) sucked upon
(4) radial angular deformity at the wrist of the target thumb
(5) acute bite marks on the skin
(6) callus formation
(7) infection (cellulitis, other)
Emotional complications:
(1) taunting by peers
(2) shaming by parents trying to stop the habit
A child who persists in thumb sucking may be trying to console him/herself in the face of an emotional problem that is the cause rather than the consequence of digit sucking.
