Thumb sucking

Thumb sucking is a behavior found in humans, chimpanzees, captive Ring-tailed Lemurs,[1] and other primates.[2] It usually involves placing the thumb into the mouth and rhythmically repeating sucking contact for a prolonged duration. It can also be accomplished with any piece of skin within reach (such as the big toe) and is considered to be soothing and therapeutic for the person. As a child develops the habit, it will usually develop a "favorite" finger to suck on.

At birth, a baby will reflexively suck any object placed in its mouth; this is the sucking reflex responsible for breastfeeding. This reflex disappears at about 4 months of age; thumb sucking is not purely an instinctive behavior and therefore can last much longer.[3] Moreover, ultrasound scans have revealed that thumb sucking can start before birth, as early as 15 weeks from conception; whether this behavior is voluntary or due to random movements of the fetus in the womb is not conclusively known.

Thumb sucking generally stops by the age of 5 years. Some older children will retain the habit, which can cause severe dental problems. Thumb sucking is sometimes retained into adulthood and may be due to stereotypic movement disorder, another psychiatric disorder, or simply habit continuation.

Contents

Dental problems and prevention

Percentage of children who suck their thumbs (data from two researchers)

Age Kantorowicz[3] Brückl[4]

0–1
1–2

 92%
93%		 66%
2–3 87% –
3–4
4–5
5–6		 86%
85%
76%		 25%
Over 6 — 9%

Most children stop sucking on thumbs, pacifiers or other objects on their own between 2 and 4 years of age. No harm is done to their teeth or jaws until permanent teeth start to erupt. The only time it might cause concern is if it goes on beyond 6 to 8 years of age. At this time, it may affect the shape of the oral cavity or dentition.[5]

To prevent their children from sucking their thumbs some parents use bitterants or piquant substances on their child's hands—although this is not a procedure encouraged by the American Dental Association[5] or the Association of Pediatric Dentists. During the 1950s, parents could get a series of sharp prongs known as "hay-rakes" cemented to a child's teeth to discourage sucking.

The American Dental Association recommends:

See also

References

  1. ^ Jolly, A. (1966). Lemur Behavior. Chicago: University of Chicago Press. p. 65. ISBN 978-0226405520. 
  2. ^ Benjamin, Lorna S.: "The Beginning of Thumbsucking." Child Development, Vol. 38, No. 4 (Dec., 1967), pp. 1065–1078.
  3. ^ a b A. Kantorowicz: "Die Bedeutung des Lutschens für die Entstehung erworbener Fehlbildungen." In: Fortschritte der Kieferorthopädie. Bd. 16, Nr. 2, 1955, S. 109–121.
  4. ^ Erwin Reichenbach, Hans Brückl: Kieferorthopädische Klinik und Therapie. J. A. Barth, Leipzig 1962
  5. ^ a b http://www.ada.org/2977.aspx

External links