Thumb sucking that persists beyond the eruption of primary teeth can, and usually does, cause improper growth of the mouth and misalignment of the teeth.
The most obvious sign that a child sucks their thumb is changes to the front teeth. The sucked thumb or finger can cause the upper front teeth to protrude forward. This protrusion is also known as an overbite, or ‘buck teeth’. The constant pressure from the hand in their mouth can also cause the lower front teeth to tip forward.
An open bite can also occur with thumb sucking. This means the upper teeth don’t overlap the bottom teeth when the back teeth are together. The thumb or finger has created an opening between the top and bottom front teeth and prevents them from meeting.
