Thumb sucking
Thumb sucking is a common behavior observed in infants and young children, with approximately 80% of infants engaging in this habit. While many children naturally outgrow thumb sucking, about 30% continue the behavior beyond their first year, and 12% still suck their thumbs at age four. Primarily, thumb sucking serves a comforting purpose, helping children self-soothe during stressful moments, such as teething or fatigue, and can promote a sense of independence when children are engaged in this self-stimulating activity.
However, prolonged thumb sucking can lead to various issues, particularly if it persists past the age of four. Potential negative effects include dental problems, speech delays, and social challenges, as children who suck their thumbs may be perceived less favorably by peers. Furthermore, parents often express concern about this behavior, which can inadvertently reinforce the habit. Approaches to address thumb sucking vary, and treatment is generally recommended only when the negative consequences outweigh the benefits. Perspectives on this behavior have evolved over time, with some viewing it as a natural phase and others as a concern that requires intervention.
Thumb sucking
Anatomy or system affected: Mouth, teeth
Definition: A common oral behavior among young children that may cause physical, psychological, and social problems if it is continued past a certain age
Physical and Psychological Factors
It has been estimated that 80 percent of all infants and babies suck their thumbs. However, many continue this habit as they age. While 30 percent continue to suck their thumbs past one year of age, and 12 percent are still engaging in thumb sucking by the age of four. By age five, the occurrence of thumb sucking generally begins to fade during the daytime. If children continue to suck their thumbs, it is generally limited to nighttime. One in eight children has been found to participate in prolonged thumb sucking into ages seven through eleven.
Thumb sucking is reinforcing to children because of its soothing property. For example, it is often observed among children when they are tired, frustrated, hungry, or uncomfortable, such as when teething causes discomfort. Children often use thumb sucking as a means to fall asleep. Furthermore, thumb sucking tends to increase the level of independence in infants. This becomes evident when observing an infant who is occupied by this self-stimulating behavior.
Disorders and Effects
Although thumb sucking is relatively harmless among children younger than three years of age, problems can develop if the behavior persists. Negative consequences may consist of dental problems, inhibited speech development, and critical peer and parental reactions.
One of the main problems associated with thumb sucking is dental problems, especially if this behavior persists after the age of four or five. Thumb sucking can also inhibit speech development in formal and informal settings at school or daycare. For example, when children are sucking their thumbs during formal group activities, they are less likely to respond to adult questions. Also, during free-play time, children who are sucking their thumbs are less likely to speak spontaneously. Thumb sucking may also affect the ability of young children to pronounce words properly.
In addition to causing problems for speech and physical development, thumb sucking can create social difficulties for children. According to the Pediatrics article, “Influence of Thumb Sucking on Peer Social Acceptance in First-Grade Children,” by P. C. Friman and colleagues, “Social acceptance is lower among children who suck their thumb, and they are viewed by their peers as being less intelligent, happy, attractive, likable, or fun, and less desirable as a friend, playmate, seatmate, classmate, or neighbor.” Furthermore, thumb sucking can create negative interactions between parents and children. Because parents are often troubled by thumb sucking, children are routinely asked to stop. These requests can be positively reinforcing to the child and can increase the frequency of the behavior.
Given the problems associated with thumb sucking, many parents wonder at what point in time a child should be treated for this behavior. In their 1989 article, “Thumb Sucking: Pediatricians’ Guidelines” in Clinical Pediatrics, Friman and B. D. Schmitt provided some guidelines to answer this question. As a simple rule, thumb sucking should not be treated until the potential negative consequences outweigh the benefits, which is seldom before the age of four. When children do suck their thumbs, often, it is not frequent enough to warrant treatment. They also point out that, at times, the potential benefits may outweigh the risks, such as when a child uses thumb sucking as a means of coping with fear, pain, or a significant loss. As suggested by these authors, another indication for treatment is chronic thumb sucking, which they define as occurring “across two or more settings (e.g., home and school) and when it occurs day and night.”
Both positive and negative reinforcement techniques have been used to treat persistent thumb sucking. These include offering other types of stimulation or comfort (depending on whether the cause is boredom or stress), rewarding the child for not sucking their thumb, involving the child in breaking the habit, and applying bitter substances to the thumb as a deterrent. As with reprimands, the utility and ethics of other negative reinforcements, such as bitter coatings, continue to be debated. If the child has turned to sucking their thumb as a replacement for previously usually a pacifier, the situation may be more complicated.
Perspective and Prospects
Attitudes toward oral behavior in children have fluctuated over the years. It has been viewed as both indulgent and detrimental. There have been high and low attempts to prohibit the activity. Sigmund Freud, though largely discredited in the twenty-first century, and his colleagues did much to draw attention to the oral drive in the first year of life, and over the years, many writers have made observations about oral habits and psychological health.
The advent and wide use of pacifiers have done much to neutralize concern over oral behaviors. Pacifiers are generally seen as preferable to the thumb from a dental perspective. Thumb sucking tends to arouse more anxiety for both parents and medical specialists than does the use of the pacifier; however, pacifier use beyond age four can lead to the same types of dental problems as those caused by prolonged thumb sucking.
Bibliography
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A.D.A.M. Medical Encyclopedia. "Thumbsucking." MedlinePlus, January 24, 2011.
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Friman, P. C., K. M. McPherson, W. J. Warzak, and J. Evans. “Influence of Thumb Sucking on Peer Social Acceptance in First-Grade Children.” Pediatrics 91, no. 4 (April, 1993): 784–86.
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