Mary Brannan
Dental Hygiene Program
Spring 2001, Phoenix College
  Printed with the permission of Debby Kurtz-Weidinger, RDH, M.Ed.
Department of Dental Programs
Phoenix College

Down syndrome affects people of all ages, races and economic levels. It is the most frequently occurring chromosomal abnormality found in humans (About Down, 2001). "Each year, one child in every 800 births in the United States is born with Down syndrome. Of the approximately four million births in the United States per year 5,000 newborns with Down syndrome can be expected" (Buxton & Hunter, 1999). There are both physical and orofacial features that are characteristic of Down syndrome. Many health and dental concerns are associated with those who have Down syndrome and unfortunately there is no known effective medical treatment available at this time.

John Langdon Down who published an accurate description of a person with Down syndrome discovered Down syndrome in 1866, although he did not know the cause of the syndrome. He was then termed the "father" of the syndrome (About Down, 2001). Nearly a century later in 1959, Down syndrome was associated with an extra chromosome. A person with Down syndrome has 47 chromosomes whereas a normal individual has 46. The excess genetic material from this extra chromosome is in the form of additional genes along the 21st chromosome, resulting in the characteristics of Down syndrome. Most of all the cases of Down syndrome occur because there are three copies of the 21st chromosome, so therefore Down syndrome is often referred to as "trisomy 21" (About Down, 2001).

There are three different types of Down syndrome. The three forms are trisomy 21, translocation, and mosaicism. It is important to distinguish what type the child has, as the chance of the parents' having another child with the syndrome depends on which form their child has. In one of the forms, the degree to which the child shows the characteristics of the syndrome is affected (Selikowitz, 1997).

Nearly 95 percent of the cases of Down syndrome have trisomy 21. This is where the child has an extra 21 chromosome. This results in a total of 47 chromosomes instead of the normal 46 (Pueschel, Down syndrome).

The second type of Down syndrome is called translocation and this form is found in 3-4 percent of the individuals with Down syndrome. The extra 21 chromosome is attached or translocated onto another chromosome, usually on chromosome 14, 21 or 22. If this type is found in the child, it is important to examine the parents' chromosomes, since in at least one-third of all cases, a parent may be a carrier of translocation (Pueschel, Down syndrome).

The third type of Down syndrome is mosaicism and is found in one percent of cases of Down syndrome. In this case, some cells have 47 chromosomes and others have 46 chromosomes. This type is thought to be the result of an error in cell division soon after conception (Pueschel, Down syndrome).

Many theories have developed regarding the cause of Down syndrome, but it is not actually known. Some professionals believe that hormonal abnormalities, X-rays, viral infections, immunologic problems or genetic predisposition may be the cause. Another suggestion is that the risk of having a child with Down syndrome increases with the increasing age of the mother. However, studies show more than 85 percent of the babies born with Down syndrome are born to mothers younger than 35 years. Some investigators report that older fathers may also be at an increased risk of having a child with Down syndrome (Pueschel, Down syndrome).

There are two types of tests available to pregnant women to test for Down syndrome. The "chorionic villus sampling is preformed between nine and 11 weeks of gestation and amniocentesis is preformed at 16 to 18 weeks of gestation" (Sanez, 1999). Each one of these procedures carries a small risk of miscarriage as tissue is extracted from the placenta or the umbilical cord to examine the fetus' chromosomes. The procedures are about 98 to 99 percent accurate in detection of Down syndrome (About Down, 2001).

There are many physical manifestations that are characteristic of a person with Down syndrome. "The eyes slant upward and outward, and have an extra-thick fold of skin on the inner surface of the eye. In relationship to the rest of the body, the legs and arms are shorter, with the feet and hands rather flat and broad. A single crease is often found stretching across the palm of the hand, and the fifth finger curves in toward the other fingers" (Buxton & Hunter, 1999). The face is flat with a somewhat depressed nasal bridge and a small nose (About Down, 2001). The rest of the head is smaller than normal (Buxton & Hunter, 1999). The person with Down syndrome will suffer from muscle hypotonia. There will be an abnormal shape of the ear. The person will have hyper flexibility of the joints. There will also be excessive space between the large and second toe (About Down, 2001).

An individual with Down syndrome presents many distinctive oral manifestations as well as physical. The primary skeletal abnormality affecting the orofacial structures in Down syndrome is an underdevelopment of the midfacial region. The bridge of the nose, bones of the midface and maxilla are relatively smaller in size (Pilcher, 1998). "The palate is smaller than average, and the mandible extends too far anteriorly" (Buxton & Hunter, 1999). In many instances this causes a prognathic class III occlusal relationship, which contributes to an open bite (Pilcher, 1998). Individuals with Down syndrome have delayed eruption patterns and eruption patterns that are atypical of both the primary and permanent dentitions. There is usually some sort of enamel defect affecting the teeth. There is usually congenitally missing teeth and they can have unusually shaped teeth.

Children with Down syndrome are at an increased risk for many health problems. Some of these health concerns may be more serious than others. Although, most patients will require yearly or more frequent exams by a specialist.

Children with Down syndrome often have more eye problems than other children who do not have this disorder. The children can suffer from cataracts, farsightedness or nearsightedness. Numerous children are cross-eyed, have inflammation of the eyelid margins and sometimes rapid eye movements. A pediatric ophthalmologist should examine the individual regularly (Pueschel, 1998).

60 to 80 percent of children with Down syndrome have hearing deficits (Pueschel, Down syndrome). The hearing loss may be due to increased wax in the ear canal, frequent ear infections, fluid accumulation in the middle ear, and or abnormally shaped small bones in the middle ear. The hearing loss may be also associated with a problem of drainage of fluid from the middle ear to the throat because of congestion, upper respiratory infections, large adenoids or Eustachian tube dysfunction (Pueschel, 1998).

Approximately 40 to 45 percent of children with Down syndrome have congenital heart disease. The most commonly seen problem concerns the central part of the heart, where holes in the wall between the chambers and abnormal development of the heart valves may be present (Pueschel, 1998). Many of these children will have to undergo cardiac surgery and often will need long term care by a pediatric cardiologist (Pueschel, Down syndrome).

Skeletal problems in Down syndrome are common and may be found in many parts of the body. The major concern relates to the easily stretched ligaments in these individuals. The majority of children with Down syndrome have hyper extensible joints. This leads to an increased risk of dislocations of the kneecap and the hip (Pueschel, 1998).

Thyroid gland dysfunctions are more common in children with Down syndrome than in normal children. Between 15 and 20 percent of children with Down syndrome have hypothyroidism. It is important to examine the child's thyroid function to prevent compromising normal central nervous system functioning (Pueschel, Down syndrome).

Other important medical aspects that a person with Down syndrome may suffer from are congenital anomalies of the gastrointestinal tract, sleep apnea, immunologic concerns, leukemia, Alzheimer disease, seizure, and skin disorders. All of these may require the attention of specialists in their respective fields.

There are many systemic factors influencing dental care of a patient with Down syndrome. One factor is regarding Mitral Valve Prolapse. 50 percent of adults with Down syndrome develop Mitral Valve Prolapse by adulthood and require sub acute bacterial endocarditis prophylaxis for dental treatment. Another factor is that a compromised immune system contributes to a higher rate of infections and is also a contributing factor in the high incidence of periodontal disease. Also, children with Down syndrome have chronic upper respiratory infections. These contribute to mouth breathing and its associated effects of zerostomia and fissuring of the tongue and lips. There is also greater incidence of apthous ulcers, oral candida infections and ANUG. Another factor is regarding the reduced degree of muscle tone generally found on Down syndrome. The reduced muscle tone in the lips and checks contribute to an imbalance of forces on the teeth with the force of the tongue being a greater influence. This contributes to an open bite. Reduced muscle tone causes less efficient chewing and natural cleansing of the teeth. More food may remain on the teeth after eating due to this inefficient chewing (Pilcher, 1998).

Children with Down syndrome should be educated in proper oral hygiene. The first dental appointment for the child should be at one year of age. At this appointment, the dental hygienist should examine the child and discuss dental caries and periodontal disease with the parent or care giver. The relationship between cariogenic foods and plaque should be discussed. As the teeth begin to erupt it is important to teach the child's caregiver how to properly remove dental plaque. Children with Down syndrome may experience a delay in developing fine motor skills. The parent or caregiver will have to brush and floss the child's teeth until the child is able to do it. Automatic toothbrushes and floss aids are highly recommended (Buxton & Hunter, 1999).

There is a high rate of periodontal disease in people with Down syndrome. Early to severe periodontal disease is often seen with onset in the mid to late teen years. Some studies report an incidence of periodontal disease to be between 90 to 96 percent of adults with Down syndrome. It is thought to be related to a lowered host immune response due to the compromised immune system in Down syndrome. The teeth most often affected are the maxillary molars and the mandibular incisors. Good oral hygiene and semi-annually prophylaxis appointments may not be enough to prevent the progression of periodontal disease in these patients. Early, aggressive periodontal therapy is needed. These patients may need to be seen as often as every three months for scaling and root planing. They may also benefit from the use of chlorhexedine mouth rinse and possibly systemic antibiotic therapy (Pilcher, 1998).

Most patients with Down syndrome can handle routine dental care with just a little more time and attention given during the appointment. Dental appointments are more beneficial if scheduled early in the day because the patient and the operator are more rested. First appointments should be for orientation only and subsequent appointments may require a little more time than what is usually allowed. Also, one must be prepared that a medical consult may be needed. Treating the older patient with Down syndrome may prevent more difficulties due to the high incidence of Alzheimer's disease in these patients. The average age of onset of clinical symptoms is between 40-50 years old. These patients will require a great deal of understanding and their level of cooperation may decrease as the disease progresses (Pilcher, 1998).

Many medications and various therapies have been promoted for people with Down syndrome, but there is no known effective medical treatment available at this time. Some medical therapies include thyroid hormone, pituitary extract, glutamic acid, massive vitamin and mineral therapy, dimethyl sulfoxide, Sicca cell and a precursor of serotonin, which is 5-hydroxytryptophan. None of these drug treatments have shown to be effective for children with Down syndrome. Other forms of therapy include sensory integration therapy, specific types of diets, developmental optometry and chiropractic therapy. These also have not been shown to help children or adults with Down syndrome.

Plastic surgery is also a treatment option for those who have Down syndrome. Silicone implants can be inserted under the skin to build up the bridge of the nose, the cheeks, and the chin. These are usually relatively minor procedures, requiring general anesthetic and a couple of days in the hospital (Selikowitz, 1997). Surgery can also involve removal of the folds between the nose and ears, straightening out of the slightly slanted eyelids, and removal of part of the tip of the tongue. The surgery on the tongue is a major surgical procedure. Since the tongue is a vascular mobile organ, and complications, such as infection, wound opening, and obstruction to breathing may occur during the first four to six weeks after the operation, when the tongue is very swollen. There is a decrease in the taste sensation as some of the taste organs are removed during the operation (Selikowitz, 1997).

People with Down syndrome are people first. They are unique and must be not only treated as an individual, but also as an equal. Over the past few decades, beginning with section 504 of The Rehabilitation Act of 1973, continuing with The Education Act of 1975 and finally ending with the passage of The Americans with Disabilities Act in 1991, people with Down syndrome have been granted equal protection under federal law (About Down, 2001).

Early intervention programs, preschool nurseries, and integrated special education strategies have demonstrated that youngsters can participate in many learning experiences. These experiences can positively influence their overall functioning (Pueschel, Down syndrome). People with Down syndrome venture out into the community, they attend schools, have jobs and are involved in leisure activities. Some live with family, some with friends and some independently. They form ongoing interpersonal relationships and some may marry. Women with Down syndrome are fertile and can have children (About Down, 2001).

In conclusion, the entire dental team needs to be aware of the health and dental concerns associated with those who have Down syndrome. The dental hygienist has the opportunity to teach the Down syndrome patient and their caregiver effective home care. The dental hygienist has the ability to make a positive difference in the oral health of a patient with Down syndrome.


About Down Syndrome, Retrieved March 20, 2001 from World Wide Web: ttp://

Buxton, R., & Hunter, J. (1999). Understanding Down's Syndrome: A review. Journal of Dental Hygiene, 73, 99.

Pilcher, E.S. Dr. (1998). Dental Care for the Patient with Down Syndrome. Down Syndrome Research and Practice, 5, 111-116.

Pueschel, Siegfried M. (1990). A Parent's Guide to Down Syndrome. Baltimore: Paul H. Brooks Publishing Co., Inc.

Pueschel, Siegfried M. Down Syndrome, Retrieved March 19, 2001 from the World Wide Web: [Not available]

Saenz, R.B. (1999). Primary Care of Young Children with Down Syndrome. American Family Physician, 59, 381.

Selikowitz, M. (1997). Down Syndrome the facts. New York: Oxford University Press, Inc.