Aim: Finger sucking is frequently found in children and sometimes in adults too. Often reasons are found to explain why certain children feel the need to suck their thumbs or fingers, but these explanations are always derived from clinical observation without any rational support, searching for motives for this bad habit from family life; strict parents, jealousy at the birth of a sibling, difficulty accepting the end of breastfeeding etc. Some think that a child should continue to suck after actual nutrition has ended and the substitution of the mother's nipple with a thumb or finger could fill this need. Research however, using anatomical and neurophysiological data, explains why an infant forms the habit of thumb sucking from a neurological standpoint abandoning the psychological explanations proposed until now.
Methods: Forty thumb-sucking subjects with ages ranging from 5 to 25 years and a control group of 20 non-thumb-sucking subjects with correct swallowing patterns were analyzed evaluating postural and neurological effects of thumb sucking. Instruments used for this evaluation were a device for electromyography to measure the muscular tone and a baropodometer, stabilometer and a scoliosometer to analyse posture.
Results: Analyzed subjects had an evident improvement at the baropodometer and stabilometer and a scoliosometer examination to analyze posture and at the electromyography analysis.
Conclusion: The results obtained confirm that a thumb-sucking subject puts the thumb in the mouth to stimulate the nasal-palatal receptors of trigeminus and obtain muscular balance and a release of physical and psychological tension.