CD-ROM Today 1996 January/CD-ROM Today 1996 January.iso/dp/0397/03975.txt

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$Unique_ID{BRK03975}
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$Title{Maxillofacial Dysostosis}
$Subject{Maxillofacial Dysostosis Hypoplasia of the Maxilla Primary Familial
Acrodysostosis Hemifacial Microsomia Nager Syndrome Treacher Collins Syndrome
}
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Copyright (C) 1992 National Organization for Rare Disorders, Inc.

906:
Maxillofacial Dysostosis

** IMPORTANT **
It is possible that the main title of the article (Maxillofacial
Dysostosis) is not the name you expected.  Please check the SYNONYMS listing
to find the alternate name and disorder subdivisions covered by this article.

Synonyms

     Hypoplasia of the Maxilla, Primary Familial

Information on the following diseases can be found in the Related
Disorders section of this report:

     Acrodysostosis
     Hemifacial Microsomia
     Nager Syndrome
     Treacher Collins Syndrome

General Discussion

** REMINDER **
The Information contained in the Rare Disease Database is provided for
educational purposes only.  It should not be used for diagnostic or treatment
purposes.  If you wish to obtain more information about this disorder, please
contact your personal physician and/or the agencies listed in the "Resources"
section of this report.

Maxillofacial Dysostosis is a rare disorder inherited as an autosomal
dominant trait.  Major characteristics include an underdeveloped upper jaw,
delayed speech as well as poor articulation, down-slanting of the eyelids,
and malformations of the external ear.

Symptoms

The primary symptoms of Maxillofacial Dysostosis are delayed speech with poor
articulation, an underdeveloped upper jaw, down-slanting of the eyelids and
malformations of the external ear.

Other symptoms that have been found in some patients with Maxillofacial
Dysostosis are:  involuntary movement of the eyes (nystagmus); crossed eyes
(strabismus); an indent in the chest (pectus excavatum); incomplete or
underdeveloped nipples; a flat skull in the back; and/or a beaked nose with a
flat nasal bridge.

Although most patients with Maxillofacial Dysostosis have normal
intelligence, they are often thought to be mentally retarded due to their
language problems.  Their progress should be carefully monitored and
educators should be informed of this potential problem.

Causes

Maxillofacial Dysostosis is inherited as an autosomal dominant trait.  Human
traits, including the classic genetic diseases, are the product of the
interaction of two genes, one received from the father and one from the
mother.  In dominant disorders a single copy of the disease gene (received
from either the mother or father) will be expressed "dominating" the other
normal gene and resulting in the appearance of the disease.  The risk of
transmitting the disorder from affected parent to offspring is fifty percent
for each pregnancy regardless of the sex of the resulting child.

Affected Population

Maxillofacial Dysostosis is a very rare disorder that affects males and
females in equal numbers and is detectable at birth.  There have been
approximately twelve cases reported in the medical literature.

Related Disorders

Symptoms of the following disorders can be similar to those of Maxillofacial
Dysostosis.  Comparisons may be useful for a differential diagnosis:

Acrodysostosis is a rare disorder characterized by underdevelopment of
the jaw, improper alignment of the teeth, extremely short hands and feet, a
flattened nose, short stature, mental retardation, widely spaced eyes,
deformity of the bones in the arms, legs and elbows, and an abnormally short
broad head.  (For more information on this disorder choose "Acrodysostosis"
as your search term in the Rare Disease Database).

Hemifacial Microsomia is a syndrome that affects one in 5,000 births.
Major features of this disorder may include:  underdevelopment of the lower
jaw, tilting of the face to one side, deformities of the ear, facial nerve
weakness, underdevelopment of the cheek and eye, abnormalities of the
vertebrae and ribs, cleft lip/palate, and possibly heart and kidney
abnormalities which are very rare.

Nager Syndrome is a rare disorder characterized by underdevelopment of
the cheek and jaw area of the face, down-sloping of the opening of the eyes,
a smaller that normal jaw, lack of development of the internal and external
ear with related hearing problems, absent or sparse lower eyelashes, and/or
cleft palate.  (For more information on this disorder choose "Nager Syndrome"
as your search term in the Rare Disease Database).

Treacher Collins Syndrome is a rare disorder characterized by
underdevelopment of the cheek, lower jaw and jawbones, slanted eyes, notching
of the lower eyelids, and a receding chin.  Underdevelopment of the jaw may
cause problems in the newborn with swallowing or breathing.  The outer upper
area of the ear may be malformed as well as the external hearing canal.  The
eardrum may be replaced with a bony plate.  The combination of a longer than
normal face with a beaklike nose, receding chin and acute deafness, are
characteristic of people with Treacher Collins Syndrome.  (For more
information on this disorder choose "Treacher Collins" as your search term in
the Rare Disease Database).

Therapies:  Standard

The facial features in patients with Maxillofacial Dysostosis improve with
age often giving a near normal appearance by adulthood.  When the
malformations of the face are severe, plastic surgery and orthodontic repair
may be necessary.

Genetic counseling may be of benefit for patients and their families.
Other treatment is symptomatic and supportive.

Therapies:  Investigational

Research on birth defects and their causes is ongoing.  The National
Institutes of Health (NIH) is sponsoring the Human Genome Project which is
aimed at mapping every gene in the human body and learning why they sometimes
malfunction.  It is hoped that this new knowledge will lead to prevention and
treatment of genetic disorders in the future.

This disease entry is based upon medical information available through
April 1992.  Since NORD's resources are limited, it is not possible to keep
every entry in the Rare Disease Database completely current and accurate.
Please check with the agencies listed in the Resources section for the most
current information about this disorder.

Resources

For more information on Maxillofacial Dysostosis, please contact:

     National Organization for Rare Disorders (NORD)
     P.O. Box 8923
     New Fairfield, CT  06812-1783
     [phone]

     NIH/National Institute of Child Health and Human Development (NICHHD)
     9000 Rockville Pike
     Bethesda, MD  20892
     [phone]

     Forward Face
     560 First Ave.
     New York, NY  10016
     [phone]
     (800) 422-FACE

     FACES
     National Association for the Craniofacially Handicapped
     P.O. Box 11082
     Chattanooga, TN  37401
     [phone]

     Let's Face It
     Box 711
     Concord, MA  01742
     [phone]

     National Craniofacial Foundation
     3100 Carlisle St., Suite 215
     Dallas, TX  75204
     1-800-535-3643

For Genetic Information and Genetic Counseling Referrals:

     March of Dimes Birth Defects Foundation
     1275 Mamaroneck Avenue
     White Plains, NY 10605
     [phone]

     Alliance of Genetic Support Groups
     35 Wisconsin Circle, Suite 440
     Chevy Chase, MD  20815
     (800) 336-GENE
     [phone]

References

MENDELIAN INHERITANCE IN MAN, 9th Ed.:  Victor A. McKusick, Editor:  Johns
Hopkins University Press, 1990.  P. 602.

BIRTH DEFECTS ENCYCLOPEDIA, Mary Louise Buyse, M.D., Editor-In-Chief;
Blackwell Scientific Publications, 1990.  P. 1109.