Why we can't afford to ignore prolonged digit sucking

By Rosemarie A. Van Norman, COM

Children who persist in sucking a thumb or finger beyond early childhood risk significant dental problems as well as learning, speech, and emotional difficulties. A specialist explains the hazards and offers advice on breaking the habit.

Soothing and comforting, sucking on a thumb or finger helps infants to calm and entertain themselves. Many children discontinue the behavior in the toddler or preschool years, but millions of others continue digit sucking well beyond early childhood.

Parents whose child engages in digit sucking worry about dental and speech development as well as damage to the child's self-esteem because of taunting by peers and criticism from almost everyone including relatives, teachers, day-care providers, and even total strangers. They may wonder if their child is emotionally insecure or if they are incompetent parents. Appropriate help is often difficult to find.

Many parents seek guidance from a pediatrician. But a pediatrician who is unaware of the problems associated with prolonged sucking activity or fail to recognize the extent of parental anxiety may offer the standard advice: "Peer pressure will eliminate the habit when the child starts school" or "Ignore it, your child will stop when he or she is ready." Although well-intentioned, this advice does little to educate or reassure parents.

Without specific treatment recommendations, many parents try their own methods to eliminate the habit. When nothing seems to work, they become frustrated and often resort to negative methods, which only erode the child's self-image and entrench the sucking behavior. To help pediatricians advise parents concerned about prolonged digit sucking, I will review the problems associated with the habit and suggest an approach to eliminating it.

How does digit sucking begin?

Through ultrasound imaging, we know that many fetuses suck their thumbs and fingers in utero. Toddlers may start sucking their fingers or thumbs by mimicking a playmate or other children at preschool or day care. It is not unusual to find several youngsters in one family with digit-sucking habits as a direct result of one child imitating another. This is particularly true if a revered older sibling sucks a digit.

A common misconception holds that children who suck a pacifier rarely suck thumbs or fingers and that using a pacifier will prevent digit sucking. Data I collected on 723 children whom I treated for digit-sucking habits revealed that 243 (34%) started habitual sucking on a pacifier.¹ They initially sucked on the pacifier only, not the pacifier and a digit. When they were able to bring their hands to their mouths effectively and the pacifier was unavailable, they started sucking a much handier digit. This substitution also occurs when parents of a toddler decide to eradicate a pacifier habit. Pacifier-sucking children may develop a habit of sucking on the tongue, lower lip, blanket, or other object when the pacifier is taken away.

How common is digit sucking?

Estimates of the incidence of non-nutritive sucking—thumbs, fingers, pacifiers—range from 75% to 95% of infants in Western cultures.² 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%).³ 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.^4,5

Although no incidence studies of adult digit sucking exist, it is far more widespread than most realize. I have communicated with many people preparing to enter college who are concerned that their digit sucking, while sleeping, will be discovered in the dormitory. A recent newspaper article reported that, when a Web page dedicated to adult digit suckers was featured on a television show, the site received an average of 800 hits a week from adults seeking advice about their digit sucking habit.⁶

Several surveys have found digit sucking to be more common in girls.^1,4,5,7-9 It is also more protracted and severe.¹⁰

Why does digit sucking persist?

Why does this normal infant behavior continue into childhood, adolescence, and even adulthood? The basis is biologic, physiologic, and psychological. Many activities create changes in mood through increased and decreased neurotransmission and subsequent alterations in brain chemistry.¹¹ Digit sucking falls into this category.

Decreased neurotransmission during digit sucking induces a calming, relaxing feeling of euphoria that is associated with the production of endorphins, which also reduce feelings of discomfort or pain. When infants discover the comforting, enjoyable physical associations of sucking a pacifier, thumb, or finger, they repeat the behavior. As time passes, they often indulge in the activity unconsciously. Some cues that stimulate digit sucking are fatigue, hunger, fear, boredom, excitement, and physical or emotional stress. Obviously, not everyone who indulges in a pleasurable activity such as digit sucking becomes obsessed with it. Perpetuation of the behavior in a particular child depends on a combination of physical cues and emotional circumstances.

What dental problems does digit sucking cause?

It is widely assumed that the most common reason for the need to straighten teeth is a genetic tendency. Actually, although research has not yet determined how much of a given child's problem is related to genetics and how much is influenced by environment, several studies have concluded that 40% or less of dental malocclusion can be ascribed to hereditary factors.^12,13 A study of 15,000 children in one orthodontic clinic concluded that a sucking habit caused 60% of the dental malocclusions seen in these patients.¹⁴

As in all pathology, the disease of one part inevitably affects the whole. Pressures applied by the digit and oral facial musculature can influence the positions of teeth and the formation of bony oral structures. 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.¹⁶ Types of malocclusions associated with digit sucking include anterior open bite, overjet and maxillary protrusion, posterior crossbite, and class II jaw relationship (retrusion of the mandible), all of which can lead to a variety of secondary problems.

Anterior open bite

Anterior open bite is the most common type of dental malocclusion associated with digit sucking.^15,17,18 The back or side teeth come together, but the upper and lower front teeth do not (Figure 1). An anterior open bite compromises chewing efficiency. Children with this condition often swallow food whole and may complain of bowel and stomach discomfort. Chewing with the mouth open is common because the opening between the upper and lower front teeth makes it difficult to keep food within the dental arches. Other problems associated with anterior open bite include:

Temporomandibular joint disorders (TMD).^19,20 Because only the side teeth come together for biting and chewing, the uneven distribution of pressure can promote bruxism (clenching and grinding of the teeth). The oral and facial pain that is common in TMD is significantly associated with bruxism, thumb- or finger-sucking, and fingernail biting, and the associations are apparent as early as 5 years of age.⁴ Symptoms of TMD include pain in the head, face, ear, neck and shoulder; osteoarthritis; limited ability to open the mouth; muscle spasm; dislocation and locking of the jaw; vertigo; and ringing in the ears. Since normal disarticulation of the molars is facilitated by contact between upper and lower incisors (incisal guidance), the open bite obliges the temporomandibular joint to separate the posterior teeth itself, a process that can distress the joint over time.²¹

Oral facial myofunctional disorder (OMD), commonly referred to as tongue thrust, is sometimes called an infantile swallow because all babies swallow with the tongue functioning low and forward in the mouth.²² The prevalence decreases to about 33% at 8 years of age as the tongue moves upward into the palate for swallowing.²¹ Approximately 98% of children with an anterior open bite retain a tongue-thrust swallowing pattern, however. The tongue must fill the gap between the upper and lower front teeth to create an oral vacuum or seal for swallowing (Figure 2).²³ Repeated pressure of the tongue against and in between the teeth may exacerbate the open bite. OMD can lead to other problems as well, including recurrence of anterior open bite after orthodontic correction (and even after maxillary surgery) and speech distortion of the sibilants /s/ and /z/ and the lingual alveolar consonants /t/, /d/, and /l/.^21,24 OMD can make it difficult to correct these distortions by traditional speech therapy alone, and few speech therapists have had appropriate training in treating OMD.²⁵

Atypical root resorption (ARR). The pressure of a permanent tooth erupting under the primary tooth causes the roots of the primary tooth to lose structure (resorption) and eventually fall out (exfoliate). This process begins with the maxillary central incisors around 6 years of age to prepare for emergence of the permanent teeth at around 7 years.²⁶ The pressures associated with digit sucking may hasten or accentuate root resorption of the primary teeth.²⁷ Loss of a primary tooth before the permanent tooth begins eruptive movements may in turn delay eruption of the permanent tooth if the alveolar process reforms on top of the permanent tooth.²⁸ As a result, adjacent teeth may drift into the gap created by the loss of the primary tooth, leading to crowding when the permanent tooth erupts.

ARR has been associated with prolonged digit sucking and can also affect permanent teeth, causing mobility and total exfoliation.²⁹ Permanent tooth root resorption is more common in children with an open bite malocclusion and more severe in girls than boys, perhaps reflecting the greater incidence and severity of digit sucking among girls.^29,30

Teeth that show radiographic evidence of ARR before orthodontic treatment are twice as likely to undergo further resorption with the pressures of orthodontic appliances. The degree of resorption depends on the severity of the malocclusion and duration of treatment.²⁹ Digit sucking should therefore be discontinued before the permanent maxillary incisors erupt at 6 to 8 years of age to reduce the severity of the malocclusion and length of treatment.

Overjet and maxillary protrusion

Digit sucking is significantly associated with overjet and maxillary protrusion (Figure 3).^15,18 Dental trauma and fractured teeth are twice as common in children who have protruding maxillary incisors as in those with normal occlusion.^16,31

Overjet, digit and pacifier sucking, and documented trauma have been found to be risk factors for development of ARR on primary maxillary incisors.³ Overjet, trauma to maxillary incisors, OMD, digit sucking persisting beyond 7 years of age, and certain types of orthodontic treatment contribute significantly to ARR of the permanent maxillary incisors.¹⁶

Posterior crossbite and class II jaw relationship

During digit or pacifier sucking, the muscles in the cheeks contract inward against the upper dental arch, narrowing it. At the same time, the sides of the tongue move outward in a lateral direction, promoting expansion of the lower dental arch. This process can create a posterior crossbite (bilateral or unilateral) with one or more of the upper side or back teeth positioned inside rather than outside the lower dental arch (Figure 4).³² The condition is rarely self-correcting.³³ Digit and pacifier sucking significantly increase the prevalence of posterior crossbite, especially in girls.³⁴

Problems arising from bilateral posterior crossbite (both sides of the mouth) include high, narrow palatal development, resulting in crowding of all the teeth in the maxillary arch, and OMD. Unilateral posterior crossbite (one side of the mouth) causes lateral shifting of the mandible to maintain a functional relationship with the upper teeth, which results in OMD; accidental laceration of the inner cheeks during biting and chewing^1,9; speech distortion, specifically a lateralized (slushy sounding) /s/²¹; temporomandibular joint changes³⁵; TMD caused by unbalanced muscle hyperactivity from lateral shifting of the mandible, which influences the morphology of the temporomandibular joint³⁶; and asymmetric craniofacial growth resulting from dental compensations and undesirable growth modifications produced by uncorrected crossbites.³³

Invasive maxillary surgery is often the only option for correcting posterior crossbite once skeletal growth is completed. Early correction in the primary and mixed dentition often prevents development of a crossbite in the permanent dentition. There is no point in beginning treatment unless the sucking habit is discontinued, however, because the correction can relapse.

Class II jaw relationship (retrusion of the mandible) is often considered congenital. Digit sucking can exacerbate this type of malocclusion, however, by pulling forward the maxillary teeth and maxillae. An increased tendency toward class II relationship and permanent malocclusion has been noted in children who continue the sucking habit after 4 years of age.¹⁸

Discontinuing digit sucking can dramatically improve dental malocclusion, even without additional treatment (see "How kicking the habit can help," below).

How digit sucking affects learning

Protracted digit sucking can have a negative impact on the learning process whether or not the child sucks the thumb or fingers at school. Many children will not suck in front of their peers or in the classroom setting. However, oral fixation, frustration, and the effort not to suck, often lead them to chew on pencils, clothing, hair, and fingernails, so they end up with two oral habits, sucking and chewing.^1,9 Fingernail biting and digit sucking are significantly associated with TMD and facial pain.⁴ The child who is trying to control sucking activity in the classroom also may exhibit disruptive behavior and have difficulty sitting still. And the child almost instantaneously resumes digit sucking while riding home in the car or on arriving home after school.^1,9

If the child cannot restrain digit sucking at school, it may limit writing, manipulative skills, general class participation, and interaction.^1,9,37 Digit sucking can induce a trance-like state and inhibit the ability to focus on subject matter in class.^1,9 It can limit communication if the child puts the digit in the mouth often or has speech problems related to the habit. Parents often comment on the improvement in scholastic achievement and verbalization when their child's sucking habit is eliminated.

Other problems

Digit sucking can cause physical problems other than dental malocclusion and lead to psychological trauma. Physical problems include sore and infected fingernails,³⁸ calluses, crooked finger(s) (more prevalent in girls),¹⁷ and unlimited access of viruses and bacteria to the mouth. In addition, behaviors such as hair twirling or pulling (resulting in bald spots), nose picking, genital fondling, and caressing self or others often become part of the sucking ritual. They usually stop automatically when the sucking habit is eliminated.^1,9

It is a common assumption that children with a digit-sucking habit are emotionally insecure. Often, however, it is the habit and the negative response of others to it that lead to emotional trauma. Atypical dental and speech development can compound the psychological distress.

Several studies have reported negative peer and parental attitudes toward digit sucking.^1,9,39 Friman and Schmitt found that first-graders rated children who sucked their thumb to be less happy, less attractive, and less likable and were less likely to choose a thumb sucker as a friend.⁴⁰ Children can be cruel and brutally frank; a child with a sucking habit is likely to be rejected by peers, resulting in feelings of inadequacy. Rather than inhibiting the behavior, rejection often sets in motion a vicious cycle, stimulating a desire for more sucking and the relief produced by the activity. Eventually, the child may become withdrawn and anxious or angry and aggressive toward those who taunt him.^1,9

Can parents prevent digit sucking?

Parents may be able to prevent excessive dependence on sucking activity in early infancy by paying attention to the cues—fatigue, hunger, fear, boredom, excitement, physical and emotional stress—that stimulate the desire for the relief produced by digit sucking. Because infants appear calm and content when they are sucking, parents or caretakers may be lulled into believing that the child does not need immediate attention and postpone attending to the baby's needs. If this pattern is repeated often, the infant may establish a habit of compulsive sucking.

Regular sleeping and feeding prevent the cues of fatigue and hunger. Infants who are kept warm and comfortable with clean, dry diapers are less likely to become physically distressed. Sucking activity cannot rival the deep gratification of a parent's hugging, cooing, singing, and talking to the infant. A wide variety of colorful objects of various textures to touch and explore provide sensory experiences, keep the hands occupied, and limit digit sucking.

When considering child-care arrangements, parents should talk to other parents whose children attend the facility and stop by the facility unannounced during working hours. Do the children appear to be happy and busy with a wide choice of activities? Busy children do not tend to indulge in excessive sucking. Is there an adequate ratio of staff to children? If not, the staff may not have enough time to provide youngsters with the stimulation of creative play and learning. If staff turnover is high, children will have a difficult time getting the intimate, comforting relationship with an adult that is so necessary to emotional well-being and to relieve the anxiety of separation from parents.

Children can be overwhelmed by a fast-paced lifestyle. Today, both parents in most families work outside the home, and often have many extracurricular activities and commitments, all of which can cause stress and tension within the family. Youngsters need time to be children, to play, and to spend relaxed one-on-one, quality time with their parents. Setting firm priorities and limits on activities and commitments helps reduce pressure and nurture the family alliance.

What about pacifiers?

The potential for excessive pacifier sucking is great because children learn to suck on pacifiers along with everything else they are doing, including talking. The effect of frequent pacifier sucking on speech and language development is unknown. It is certainly plausible, however, that excessive pacifier use may limit babbling and imitation of sounds or words. Children may try to vocalize around the pacifier or make no attempt to articulate.

All infants need some self-comforting activity. Sucking a pacifier is soothing for a baby who is often distressed. If the infant is sufficiently contented and can be comforted in other ways, however, it is better to avoid a pacifier. The mouth helps babies to learn about and explore everything in their new world. What a shame to plug it up with a pacifier! Counsel parents to try to avoid overusing the pacifier or using it merely for their convenience. When it is time to eliminate the pacifier, around 2 years of age, gradually limiting its use lessens the likelihood that the child will begin sucking on a thumb or finger.

Why some children have trouble quitting

Inappropriate timing, inadequate understanding of the physical and emotional cues that stimulate sucking behavior, and "burnout" are the most significant reasons children have difficulty overcoming a sucking habit. Many parents unwittingly entrench the behavior by trying to eliminate the habit too soon—before the child can understand why digit sucking is a problem or has achieved adequate emotional development to practice self-control.

Parents usually begin by using gentle reminders, charts, prizes, bribes, Band-Aids, socks, and gloves. When these techniques fail, frustration sets in and parents resort to punitive measures such as foul-tasting liquids painted on the offending digit, nagging, denying privileges, or shaming the child. Such tactics only create anxiety and physical discomfort—the very cues that stimulate the desire for the relief that digit sucking provides.

When to begin breaking the habit

In deciding when to begin a program to eliminate a sucking habit, it is important to consider the child's intellectual and emotional stage of development. The child should be able to:

• understand cause-and-effect relationships

• grasp another person's point of view

• comprehend concepts of time

• have some appreciation of intrinsic values (doing something out of a sense of personal pride and self-worth because it is the right and desirable thing to do)

• discriminate between right and wrong

• practice some degree of self-control and self-denial.

Most 5-year-olds are mature enough to meet these criteria. Preschool children are not. It is inappropriate to impose the task of habit breaking on preschoolers because they are egocentric and dominated by sensory impressions. They only know the pleasure they derive from digit sucking and cannot understand why adults want them to quit.

Preschoolers have difficulty comprehending abstract concepts, logical reasoning, and cause-and-effect relationships. Comments about crooked teeth from digit sucking have little impact because preschoolers are not concerned about appearances. They could care less about having their shoes on the wrong feet, debris encrusted in their nose, last night's pizza smeared all over their face, or their hair standing on end.

Preschoolers also live minute to minute, hour to hour, understanding only here and now. When parents promise a reward next week for avoiding digit sucking, they may as well be talking about 100 years from now. Preschoolers know nothing about patience, self-control, or self-deprivation.

Children rely on the tranquilizing effects of sucking to induce relaxation and sleep at bedtime, and overcoming this dependence is hard for any child, regardless of age. The difficulty is compounded in preschoolers because nightmares are common in this age group, with their "fantasy oriented" stage of development and vivid imaginations. It is unreasonable to expect children to give up the comfort of digit sucking when they truly believe that monsters lurk under their bed.

Preschoolers can be cajoled into trying not to suck by the promise of a reward, but will often hide under a blanket and sneak a little suck, then deny the transgression. They are not lying deliberately because they have not reached the stage of development where they can understand being dishonest. They simply do not want to miss out on the promised treat and cannot sort out what they wish had happened from what really did. Regrettably, many parents do not understand the reasons behind chronic relapses and continue prodding the child to give up the habit, which only stimulates more sucking.

Because many preschoolers are very articulate, it is easy for parents to assume that they are more mature than they actually are. If pressed beyond their capabilities, these children suffer "burnout" and frustration to the point where they resist any program to eliminate the sucking habit. Each time they try and fail, they lose self-confidence and eventually come to believe they cannot succeed.

Because children depend on digit sucking to relieve stress, careful deliberation must be given to picking a time to break the habit when the child and parents are not experiencing excessive stress or change in their lives. And it is very important to view stress factors from the child's perspective and stage of development. Events such as the arrival of a new sibling, a family move, or starting a new school are just a few examples of situations that can create anxiety in a young child.

Motivating the child

The first step in breaking a sucking habit is to motivate the child to want to give it up. Parents can help get the child's commitment by:

• letting the child know that he or she is loved unconditionally and that parents want to help out of genuine concern for the child's well-being

• showing the child with a mirror what digit-sucking is doing to the teeth, such as protruding upper front teeth or a gap between the upper and lower front teeth

• discussing any sucking-related speech problems that may make it hard for others to understand the child

• pointing out crooked fingers, calluses, or baldness that are related to digit sucking

• talking about the unhealthy aspects of placing the digit with "germs" on it in the mouth

• discussing hurtful comments made by peers or others because of the sucking activity.

Rewards and reminders

Parents must help the child stay on task long enough to be certain the habit is completely eliminated. During the first week, they can give small rewards from a grab bag for good progress—for example, markers, jewelry, small toys, sugarless gum, or certificates granting special privileges, such as staying up a little later or a trip to the ice cream store. The child can pick out a reward after the first day without any sucking and then every other day. After the first week, parents can help the child make a progress chart and set some long-term goals such as a special reward at the end of two weeks without sucking, another at six weeks, and another after three months.

Reminders, such as bandages, can be introduced as special "helpers" to let the child know when the digit is trying to "sneak into the mouth." Character bandages work well as daytime reminders. Children generally need help placing the bandage comfortably on the top of the favorite digit(s).

It is important to address naptime and nighttime digit sucking at the same time as daytime sucking to break the cycle of the digit going to the mouth. Because most children who engage in digit sucking depend on it to fall asleep, and it continues sporadically during sleep, this part of the habit takes the longest to eliminate—approximately three months for most children. Parents can help by providing a calming, comforting bedtime ritual, especially during the first week. A bedtime story or backrub can be very helpful. Overstimulating physical activity and caffeine should be avoided.

A hand puppet made out of a cotton tube sock or glove can be placed on the child's hand as a nighttime reminder. It should be fastened securely or sewed to the pajama top so that it does not come off during sleep. Parents can help the child look on this method as a fun idea rather than a penalty. They should emphasize that digit sucking that occurs while sleeping is not the child's fault because "that old finger just sneaks in" and that if the sucking continues during sleep, the habit won't go away.

Tips to promote success

Two major obstacles to overcoming digit sucking are that children are often totally unaware of the activity and have limited ability to persevere. When they are trying to learn a new skill and experience frequent failure, they want to give up the task. If, for example, a bandage on the digit is used as a reminder but falls off during handwashing or play, the child may resume sucking unconsciously. Even though the lapse is unintentional, the child feels helpless, views the slip as total failure, and wants to give up immediately.

To avert such dilemmas and enhance the child's chances of immediate success, thereby encouraging perseverance, parents need to:

• be available (especially during the first two to three days), consistent, patient, and willing to focus on helping the child in a positive way

• plan activities to occupy the child's hands, such as drawing, craft projects, puzzles, and games, especially during the first two to three days while the hand-to-mouth cycle is breaking down

• understand that they are not to enforce compliance because the habit belongs to the child and he or she must be willing to cooperate if it is to be eliminated

• be aware of situations in which a reminder could come off the digit, and offer help replacing it without being intrusive

• avoid situations that stimulate sucking activity, such as excessive fatigue, hunger, television, and conflict. (Limiting television time can be helpful. So can placing a small table in front of the child with toys, crafts or art materials to occupy the hands and lessen unconscious digit sucking while the child is watching television)

• offer plenty of empathy, encouragement, and praise for the child's efforts.

The guide for parents on the below summarizes these recommendations for eliminating prolonged digit sucking.

What if parents fail?

If parents' efforts fail to end digit sucking because the child suffers burnout or the parents lose patience and conflict results, enlisting the help of a third party can make an enormous difference in achieving a positive outcome. One such third party is a certified oral myologist. Oral myology is the study of oral facial muscle function in relation to dental and speech development. Certified oral myologists are specially trained, and certified through written and clinical competency examinations, to help children overcome sucking habits quickly and without coercion (see "How a certified oral myologist can help," below).

You may want to consider referral to a certified oral myologist if:

• parents cannot motivate the child to discontinue digit sucking despite trying numerous techniques

• gentle reminders have turned into nagging, and an atmosphere of conflict, antagonism, and frustration surround the sucking behavior

• one parent is not consistently supporting or following through a habit elimination program

• two or more children in the family have a sucking habit.

Cause for concern

Considerable evidence exists that prolonged digit sucking is widespread and a source of significant, and often preventable, dental, speech, and emotional pathology. Although health-care professionals sometimes dismiss the behavior as insignificant, it is often a source of great concern to parents, who want and need help dealing with it. Further education is needed to promote understanding of the problem, and investigation is long overdue in areas such as the incidence of prolonged digit sucking; its impact on the mouth and jaws, learning, socialization, and speech development; the efficacy of standard speech remediation programs for children with an ongoing digit-sucking habit and associated OMD; and the effectiveness of treatment using both mechanical devices (such as the oral crib and habit appliances used by dentists) and motivational therapy.

In the meantime, it is appropriate to counsel parents of toddlers and preschoolers to ignore the behavior—but not indefinitely. The longer it persists, the harder it is to eliminate because emotional dependency increases with time. Breaking the habit early prevents development of pathology and avoids the need for invasive, costly treatment that may not provide an entirely satisfactory clinical result. Positive behavior modification can help children to discontinue digit sucking quickly and without coercion. The approach described here is based on sound principles of child development and addresses the biologic, physiologic, and psychological aspects of the behavior—which is as it should be, because the thumb is, after all, connected to a whole person.

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39. Wright L, Schaefer A, Solomons G: Encyclopedia of Pediatric Psychology. Baltimore, University Park Press, 1979

40. Friman P, Schmitt B: Thumb Sucking: Pediatricians' Guidelines. Clin Pediatr 1989;28(10):438

THE AUTHOR is a certified oral myologist in practice in Omaha, Neb.

How a certified oral myologist can help

A certified oral myologist can bridge the communication gap between child and parents and enter the child's world as a partner and facilitator. Trained to motivate children to want to stop digit sucking and to take responsibility for their habit, these therapists do this by developing a strong, trusting relationship. This encourages the child to feel secure that the therapist will be tolerant, patient, and empathic and to explore options in the knowledge that he or she can retreat without dishonor.

Certified oral myologists are members of the International Association of Orofacial Myology (IAOM), a nonprofit organization founded in 1972. The multidisciplinary membership includes speech pathologists, dentists, orthodontists, dental hygienists, and other allied health professionals. The IAOM is the only international accrediting organization of this therapeutic specialty. In addition to general academic preparation, certification requires training and proficiency in treating prolonged digit-sucking habits using positive behavior modification. Certified oral myologists also must understand cognitive and emotional development and the biologic, physiologic, and psychological aspects of digit sucking.

For information and to find out if any certified oral myologists practice in your area, contact:

International Association of Orofacial Myology

Office of the Executive Coordinator
970 S. Elizabeth Street
Denver, CO 80209

Telephone: (303) 765-4395;
fax: (303) 733-8006;
e-mail: jspahn@ecentral.com

The IAOM operates a Web site at http://www.iaom.com .

The parent guide on thumb or finger sucking can be photocopied and distributed to families in your practice without permission of the publisher.

GUIDE FOR PARENTS: When and how to help your child give up thumb or finger sucking

Many infants calm and entertain themselves by sucking on a thumb or finger (digit). Children usually give up digit sucking during the toddler or preschool years, but some continue it well beyond early childhood. When digit sucking persists into school years, it can interfere with proper development of the teeth, mouth, and jaw and lead to speech distortion, learning difficulties, and social rejection. The longer the habit continues, the harder it is to break. If your child is older than 5 years of age and still sucks a thumb or finger, you can help eliminate the habit:

Choose the right time. To give up digit sucking, your child must be mature enough to understand why you want him to quit and to practice self-control. Most 5-year-olds are mature enough to take on the task of quitting; preschoolers, no matter how bright and articulate, are not. Trying to get a preschooler to give up thumb sucking will likely lead to repeated relapses, frustration, conflict, and resistance. It may even make the habit worse as the child seeks comfort through increased sucking.

Choose a time to break the habit when you and your child are not experiencing excessive stress or change in your lives—such as the arrival of a new sibling, a family move, or starting a new school. Children use digit sucking to relieve stress, and trying to quit during a stressful time increases the chances of failure.

Motivate your child. Before your child can give up digit sucking, she must want to quit. To help get her commitment:

• Let her know that you love her unconditionally and that you want to help her out of concern for her well-being.

• Show her with a mirror what digit sucking is doing to the teeth, and point out calluses or crooked fingers that are related to the habit.

• Discuss any speech problems that may make it hard for others to understand her.

• Talk about the unhealthy aspects of putting a finger or thumb with "germs" on it into the mouth.

• Discuss hurtful comments made by others about the digit sucking.

Use rewards and reminders. Rewards for avoiding digit sucking can help your child stay on task long enough to make sure the habit is completely eliminated. During the first week give small rewards from a grab bag for good progress—such as markers, jewelry, small toys, sugarless gum, and certificates granting special privileges (staying up a little later, a trip to the ice cream store). Have your child pick out a reward after the first day without sucking, then every other day. Thereafter, help your child make a progress chart and set long-term goals such as a special reward after two weeks without sucking, another at six weeks, and another after three months.

Introduce reminders, such as a bandage on the finger or thumb, as special "helpers" (never penalties) to let your child know when the finger is trying to "sneak into the mouth." Character bandages work well as daytime reminders. Help your child place the bandage comfortably on the top of the finger or thumb.

Take steps to promote success. To increase the chances of immediate success and encourage your child to persevere:

• Be available (especially during the first two or three days), consistent, patient, and focused on helping the child in a positive way. Don't force her to comply. The habit belongs to her, and she must be willing to cooperate if it is to be eliminated.

• Plan activities to occupy the child's hands (drawing, craft projects, puzzles, games), especially during the first several days when you are trying to break down the hand-to-mouth habit.

• Be aware of situations in which the reminder bandage could come off the thumb or finger (such as handwashing) and offer to help replace it without being critical or intrusive.

• Avoid situations that stimulate digit sucking, such as excessive fatigue, hunger, television watching, and conflict. Most children suck their thumbs unconsciously, especially when watching television. Limit TV time and place a small table in front of your child with toys, crafts, or art materials to occupy her hands while she is watching.

• Offer plenty of empathy, encouragement, and praise for your child's efforts.

Help your child stop digit sucking at naptime and nighttime. Because most children who engage in digit sucking depend on it to fall asleep, and suck during sleep, this part of the habit takes the longest to break—usually about three months. You can help by providing a calming, comforting bedtime ritual, especially during the first week. A bedtime story or backrub can be very helpful. Avoid overstimulating physical activity or caffeine before bedtime or naptime.

A hand puppet made out of a cotton tube sock or glove can be placed on your child's hand as a nighttime reminder. Fasten it securely or sew it to your child's pajama top to prevent it from coming off during sleep. Emphasize to your child that digit sucking that occurs during sleep is not her fault because "that old finger just sneaks in." Explain that if the sucking continues during sleep, the habit won't go away.

Call our office during regular hours if this approach fails to eliminate digit sucking, if your efforts produce conflict with, or resistance from, your child, or if you have other questions or concerns.

 

Rosemarie Van Norman. Why we can't afford to ignore prolonged digit sucking. Contemporary Pediatrics 2001;6:61.