a typical though not universal habit among babies and young kids, once categorized as a habit disruption whenever continuing past 3 or 4 years. It is typically explained as a fundamental sucking urge from which the child gains satisfaction in addition to comfort and relaxation.

THUMB SUCKING: "Thumb sucking is a normal progression of development in some children, but should be discouraged at some point to protect dental health."
Cite this page: N., Pam M.S., "THUMB SUCKING," in, April 29, 2013, (accessed November 25, 2020).