Down Syndrome
Molly M. Zimmerman, B.A.
University of Pittsburgh
Department of Communication Science and
Disorders
key words: Down syndrome, orofacial anomalies
Author Information
• This lecture was authored by Molly M.
Zimmerman, an advanced graduate
student in the University of Pittsburgh
Department of Communication Science
and Disorders, School of Health and
Rehabilitation Sciences. The presentation
was prepared as a term assignment for the
graduate course Cleft Palate and
Craniofacial Disorders, taught by faculty
member Ellen R. Cohn Ph.D.
(ecohn+@pitt.edu).
Author Information Continued
Molly Zimmerman is a graduate of the
University of Pittsburgh. Her clinical interests
include adult rehabilitation as well as acute
and sub-acute care. However, she would like
to further explore her interests in child speech
and language therapy. Molly’s interest in the
lecture topic resulted from her desire to learn
more about the causes and effects of Down
syndrome.
What Will You Learn From
This Presentation?
• Causes of Down syndrome.
• Characteristics of Down syndrome.
• Medical concerns associated with Down
syndrome.
• Basic effects on speech.
Who Is Affected By Down
Syndrome?
• 1 child in every 800-1,100 births has Down
syndrome.
• 250,000 people in the U.S. have Down
syndrome.
What Causes Down
Syndrome?
• Normally, each egg and sperm cell
contains 23 chromosomes.
• The union of these creates 23 pairs, or 46
total chromosomes.
• Occasionally, an egg or sperm cell does
not develop properly and contributes 24
chromosomes instead of 23.
What Causes Down
Syndrome? (cont.)
• Down syndrome results if the extra
chromosome is number 21.
• The features of Down syndrome result
from having an extra chromosome 21 in
each of the body’s cells.
• Down syndrome is also referred to as
Trisomy 21, because of the presence of
three number 21 chromosomes.
What Does A Child With Down
Syndrome Look Like?
• May have eyes that slant upward.
• Small ears that may fold over at the top.
• Small mouth, making the tongue appear
large.
• Small nose, with a flattened nasal bridge.
• Some babies may have short necks, small
hands, and short fingers.
• Adults are often short with unusually limber
joints.
How Will Children With Down
Syndrome Develop Compared To
Other Children?
• Children with Down syndrome can do most things
that any young child can do, such as walking,
talking, dressing, and being toilet trained, but
usually develop later than other children.
• Down syndrome usually results in some degree of
mental retardation, the degree of which varies
widely. However, many will learn to read and write.
• Many people with Down syndrome hold supported
employment, and frequently live semi-independently.
Special Health Problems
Associated With Down
Syndrome
• Heart defects occur in 30-50%.
• Intestinal malformations requiring surgery occur
in 10-12%.
• Visual and hearing impairments occur in > 50%.
• Thyroid problems, adult onset leukemia, epilepsy,
diabetes, and Alzheimer's occur more frequently.
Special Health Problems
Associated With Down
Syndrome (cont.)
• Higher rate of infections due to compromised
immune system and decrease in number of T
cells.
• Dry mouth caused by mouth breathing
associated with upper respiratory infections.
• Periodontal disease accelerated by increased
number of infections.
What Extra Medical Care
Should These Children
Receive ?
• Examination by a pediatric cardiologist
and echocardiogram.
• Regular vision and hearing exams.
• Regular medical care including childhood
immunizations.
What Problems Do Infections
And Mouth Breathing Cause?
• Higher incidence of periodontal disease.
• Chronic dry mouth (xerostomia) and
fissuring of tongue and lips.
• Apthous ulcers, oral candida infections,
and acute necrotizing ulcerative gingivitis.
Orofacial Features Frequently
Associated with Down Syndrome
• Underdevelopment or hypoplasia of midfacial
region.
• Smaller bridge of nose, bones of midface, and
maxilla.
• Open bite or class III malocclusion.
• Tongue may protrude and appear too large.
Orofacial Features Frequently
Associated With Down
Syndrome (cont.)
• Sides of the hard palate are abnormally thick,
but it gives the appearance that the palate is
narrow with a high vault (Pilcher, 1998).
• Occasionally palatal cleft-like folds are found
(Desai, 1997).
• Reduced degree of muscle tone in lips and
cheeks.
Effects Of Orofacial Features
• Small nasal passage contributes to mouth
breathing.
• Less space in oral cavity for tongue effecting
speech, mastication, and natural cleansing of
teeth.
• Force of tongue greater than force of teeth
causing class III malocclusion.
Dental Anomalies In
Individuals With Down
Syndrome
• Microdentia occurs in 35-55% (Desai, 1997).
• Hypoplasia and Hypocalcification are common
(Desai, 1997).
• Congenitally missing teeth (partial anodontia)
occur in 50% of people with Down syndrome
(Desai, 1997).
• Delay in the eruption of dentition (Desai, 1997).
Effects On Speech
• Expressive language of children with Down
syndrome is commonly more delayed than
receptive language (Desai, 1997).
• Contributing factors to expressive language delay
include: mental deficiency, relatively large tongue
in a small oral cavity, excessive salivation, poor
oral closure, dry and thickened mucous, dental
anomalies, hypotonia, hearing problems, aphasia.
• Disordered articulation in children with down
syndrome reflects a delay in speech development
similar to that of normal children (Borsel, 1988).
Tongue Resection As A
Treatment For Symptomatic
Macroglossia
• Tongue reduction surgery has no effect on the
articulation of sounds (Parsons et al., 1987).
• Partial glossectomy increases aesthetic
appearance of speech, but has little or no effect
on speech intelligibility (Klaiman et al., 1988;
Margar-Bacal et al., 1987).
• Tongue resection improved deglutition and
reduced drooling (Siddiqui & Pensler, 1990).
Is There A Cure For Down
Syndrome?
• No, there is no cure.
• It cannot be prevented
• Scientists do not know why problems
involving chromosome 21 occur.
• Down syndrome is not caused by anything
either of the parents did or did not do.
Who Has An Increased Risk
Of Having A Baby With Down
Syndrome?
• Parent who already had one child with
Down syndrome.
• Parent who has a rearrangement involving
chromosome 21.
• Mother over 35 years old.
Can Down Syndrome Be
Diagnosed Prenatally?
• Yes, it can be diagnosed or more likely ruled out.
• Alpha fetoprotein (AFP) blood test, a screening
test, can be done around the 16th week of
pregnancy.
• Amniocentesis or chorionic villus sampling are
the most reliable tests used, but should be used
cautiously due to the risks associated with them.
A Quiz To Test Your Understanding
1. Is Down Syndrome caused by something
the mother does during pregnancy?
2. Can Down Syndrome be prevented?
3. What factors contribute to mouth
breathing?
4. What are some of the health problems
associated with Down Syndrome?
Check Your Understanding
1. No. Nothing the mother (or father) does
causes Down syndrome.
2. No. Down syndrome cannot be
prevented.
3. Mouth breathing occurs due to small
nasal passages and high incidence of
respiratory infections.
4. Heart defects, intestinal malformations,
vision and hearing impairments.
References
• Desai, Sindoor (1997) Down Syndrome: A Review
of the Literature.
http://altonweb.com/cs/
downsyndrome/desai.html
(7/20/99)
• Klaiman, P., Witzel, M.A., Marger-Bascal, F., Munro,
I.R., (1988). Changes in aesthetic appearance and
intelligibility of speech after partial glossectomy in
patients with Down syndrome. Plastic &
Reconstructive Surgery, 3, 403-8.
• Margar-Bacal, F., Witzel, M.A., Munro, I.R., (1987).
Speech intelligibility after partial glossectomy in
children with Down’s syndrome. Plastic &
Reconstructive Surgery, 1, 44-9.
References Continued
• Parsons, CL., Iacono, TA., Rozner, L., (1987).
Effect of tongue reduction on articulation in
children with Down Syndrome. American
Journal of Mental Deficiency, 4, 328-32.
• Pilcher, E., (1998). Dental care for the patient
with Down syndrome. The Down Syndrome
Educational Trust, 5(3), 111-116.
• Siddiqui, A., Pensler, J.M., (1990). The
efficacy of tongue resection in treatment of
symptomatic macroglossia in the child.
Annals of Plastic Surgery, 1, 14-7.
References Continued
• The March of Dimes Birth Defects
Foundation, (1997). Down Syndrome Public
Health Educational Information Sheet.
http://www.noah.cuny.edu/pregnancy/march_
of_dimes/birth_defects/downsynd.html
(7/20/99)
• Van Borsel, J., (1988). An analysis of the
speech of five Down’s syndrome
adolescents. Journal of Communication
Disorders, 5, 409-21.