Thumbsucking One of the More

Thumbsucking

One of the more common concerns among parents when preparing their young child to enter the social settings of daycare or preschool is that child's habit of thumbsucking. Sucking on the thumb or other fingers is considered to be a very normal and accepted behavior in infants in Western culture, though in some non-Western cultures (such as African or American Indian children) this habit may be less common or even missing altogether. (Leung 2001) Many psychologists believe thumbsucking is instinctive and a normal stage of childhood development. (Leung & Robson 1991) Pacifiers and other oral-comfort items are manufactured for infants to serve the same purpose as thumbsucking. The urge to suckle on fingers and inanimate objects is a natural one related to the instinct to breast feed. Almost all infants suck on their thumbs until the age of one year, and more than one third of children continue to suck on thumbs or other digits through the preschool years. (Leung & Robson 1991) "Estimates of the incidence of nonnutritive sucking -- thumbs, fingers, pacifiers -- range from 75% to 95% of infants in Western cultures. Mortelliti and Needleman reported that 37.3% of 233 children 31/2 to 5 years of age sucked a thumb (58.6%), pacifier (31%), finger(s) (8%), or other objects (2.2%)." (Norman 2001) There are slightly higher statistics of girls sucking on fingers than of boys doing so, especially in the older age groups. This behavior can actually also be observed before birth by use of a sonogram as well, as thumbsucking is very common even in the prenatal stages of development. (Oral Behaviors 1991, Norman 2001) Fetuses suck on thumbs and fingers for the same reasons that infants and toddlers do. The sensation of thumbsucking is soothing, comforting, and pleasurable. This activity is a way for infants to calm themselves when feeling stressed or uncomfortable, and also to entertain themselves when left unattended. The suckling releases chemicals in the brain that enhance the child's mood. "Sucking may be the most important volitional motor activity of the infant, since it is through sucking that the infant is able to ingest food. The choice of the thumb is most likely coincidental and probably occurs when the thumb comes into contact with the mouth in the course of random hand movement." (Leung 1991) Therefore it is beneficial from an evolutionary standpoint that this sucking would have a pleasurable reaction in the brain to encourage healthy nursing habits. Additionally, the mouth is used by infants especially as one of the primary tools of exploration and discovery as the child becomes accustomed to his or her environment and learns about the surrounding world. (Oral Behaviors 1991, Norman 2001) Other children may acquire the habit of thumbsucking from observing other children, during the toddler stages especially, and may be influenced to begin sucking from other children in daycare or on the playground and mimicking this behavior, or by observing an older sibling or relative that sucks on his or her thumb. (Norman 2001) Thumbsucking is considered to be normal until the age of four or five, depending on the developmental stage of the child, and if the habit is stopped by this age there are generally no physical or mental health problems caused by it. (Oral Behaviors 1991)

The cause for concern among health and child care workers, as well as for parents, is that many children do not stop sucking on their thumbs or other digits by the "normal" age of five years old. Many children do naturally discontinue this behavior during the toddler and preschool years of development. However, some studies have found that between five to 20% of children will continue to suck on thumbs or fingers past the age of six years old, (Leung & Robson 1991) and millions of children will continue sucking on fingers well past their early childhood. "Two other studies found that digit sucking persisted in 30% of a group of 525 4- to 6-year-olds and 26% of 371 children 6 to 9 years of age." (Norman 2001) it has also been found through studies that between 5.9% and 13.6% of children between the ages of seven and 11 years old continue to suck on their thumbs. (Garlinghouse et al. 2003) Although few studies have found any definite statistics, many teenagers and adults continue to have finger-sucking habits, especially when stressed or sleeping. (Van Norman 2001) Thumbsucking past the age of five years old can have long-lasting and serious effects on the physical and mental health of a child, as well as having negative social effects.

Many health care professionals will dismiss thumbsucking as insignificant, it is an important topic to study because it affects a majority of children in our culture for at least a period of time, and continues to affect adults who may be dealing with thumbsucking habits themselves, or those who are trying to help children who have this habit. There is not enough information available on topics such as the impact of prolonged digit sucking on the physical and other development of children. Additionally, there is not sufficient information available regarding treatments and the effectiveness of different approaches and devices intended for helping children discontinue thumbsucking. (Van Norman 2001) Three areas that need to be studied among many others are the physical health consequences of thumbsucking, the social consequences of thumbsucking, and the mental illnesses that may cause or accompany thumbsucking.

One health concern regarding thumbsucking is that children who suck on their fingers have a much higher risk of ingesting poison accidentally. "A study comparing 100 children with accidental poison ingestion and 100 children in a control group found a higher incidence of thumb sucking in the children who ingested poison (27% versus 18%)." (Leung 2001) This increase makes logical sense, because if a child were to get a toxic substance on his or her hands, it may not actually enter the body and cause harm unless the child puts his or her hands into the mouth. There is also evidence that children who suck their thumbs have a higher rate of gastrointestinal infections and other problems. (Leung 2001) Prolonged thumb sucking may also contribute to infections of the cuticles and fingernails, swollen and wrinkled skin, and even deformities of the fingers and hands. "Physical problems include sore and infected fingernails, calluses, crooked finger(s) (more prevalent in girls) and unlimited access of viruses and bacteria to the mouth." (Norman 2001) However, the most common physical health concerns associated with thumbsucking are dental. One study found that 60% of a group of 15,000 children suffering from dental malocclusion had been caused by thumbsucking. (Norman 2001) Digit sucking has been associated with several types of dental malocclusions, including anterior open bite, overjet and maxillary protrusion, posterior crossbite, and class II jaw relationship (retrusion of the mandible). These conditions vary greatly in severity. "The degree of malformation depends on the direction of the force and duration, frequency, and intensity of the sucking activity. [15] Tongue, lips, and cheeks must often compensate or adapt to the malformation to maintain functional integrity. This muscle adaptation may contribute to or accelerate the development of dental malocclusion." (Norman 2001) All of these problems can lead to secondary dental problems as well.

Socially, a child that sucks his or her thumb may have great difficulty. The learning process can be greatly affected by thumbsucking. Many children will not suck on their fingers in front of peers at school. Attempting not to suck on their fingers can be extremely distressful for children with oral fixations, and the frustration can be a significant distraction from school work. Additionally, children may start to chew on fingernails, pencils, or other objects in order to help prevent themselves from sucking on their thumb, which will lead to having an additional oral habit. Thumbsucking children often have facial and oral pain, which can additionally be a distraction from learning. The frustration of attempting not to suck on fingers will lead to disruptive behavior and difficulty sitting still in class. (Norman 2001) for those children that do not chose to -- or are unable to-- hide their thumbsucking from peers in school, there are more social difficulties. "If the child cannot restrain digit sucking at school, it may limit writing, manipulative skills, general class participation, and interaction," (Norman 2001) While sucking, the child may be distracted from the class because of the trancelike state that is often enduced by the sucking. The child may also have trouble communicating if trying to speak while keeping a finger in the mouth, or if the child suffers from other speech-related problems due to the thumbsucking. Children can be very cruel to those who thumbsuck, and the child may be bullied or rejected by his or her peers, leading to the need to find comfort in sucking even more. "Eventually, the child may become withdrawn and anxious or angry and aggressive toward those who taunt him." (Norman 2001) Obviously, thumbsucking is not an insignificant matter.

There are many possible treatment options for thumbsucking. Some of the more common treatments that are attempted by parents with or without the guidance of a professional include distraction, education, positive reinforcement, and avoidance therapy. If the child is sucking his or her thumb out of boredom or the need for comfort, a parent can help the child find another activity to distract from the sucking, or offer emotional comfort so that the child does not need to suck in order to feel loved. Many children who are old enough that thumbsucking is a concern are able to understand the reasoning behind why they should stop sucking, and teaching them about the dangers associated with it physically and socially can help them to quit. Positive reinforcement programs can include praise and rewards when children go without sucking for a certain amount of time.

Avoidance therapy can include using a bad-tasting topical application such as Stop-Zit on the thumb to make it unpleasant to suck on the fingers. (Oral Behaviors 1991) Professional methods may include aversive taste treatment with Stop-Zit, alarms that will sound when the child sucks on the thumb, and thumb posts or other prosthetics that would make it difficult or unpleasant to suck on the thumb. Of these methods, the thumb post was found in many studies to be the most effective form of therapy. (Allen & Watson 1993) Like the alarm, there are several options for awareness enhancement devices to be used in therapy. (Garlinghouse et al. 2003) Other contraptions that may be used include thumb-guards, which are wire devices put in the roof of the mouth to prevent thumbsucking. (Oral Behavior 1991) Finally, there are natural and homeopathic treatments that some people believe to be very effective, such as Saccharum. (Reichenberg-Ullman 2003)