Find information on thousands of medical conditions and prescription drugs.

Amelogenesis imperfecta

Amelogenesis imperfecta (AI) is a disorder of tooth development. This condition causes teeth to be unusually small, discolored, pitted or grooved, and prone to rapid wear and breakage. Other dental abnormalities are also possible, and the defects vary among affected individuals. These problems can affect both primary (baby) teeth and permanent teeth. more...

Home
Diseases
A
Aagenaes syndrome
Aarskog Ose Pande syndrome
Aarskog syndrome
Aase Smith syndrome
Aase syndrome
ABCD syndrome
Abdallat Davis Farrage...
Abdominal aortic aneurysm
Abdominal cystic...
Abdominal defects
Ablutophobia
Absence of Gluteal muscle
Acalvaria
Acanthocheilonemiasis
Acanthocytosis
Acarophobia
Acatalasemia
Accessory pancreas
Achalasia
Achard syndrome
Achard-Thiers syndrome
Acheiropodia
Achondrogenesis
Achondrogenesis type 1A
Achondrogenesis type 1B
Achondroplasia
Achondroplastic dwarfism
Achromatopsia
Acid maltase deficiency
Ackerman syndrome
Acne
Acne rosacea
Acoustic neuroma
Acquired ichthyosis
Acquired syphilis
Acrofacial dysostosis,...
Acromegaly
Acrophobia
Acrospiroma
Actinomycosis
Activated protein C...
Acute febrile...
Acute intermittent porphyria
Acute lymphoblastic leukemia
Acute lymphocytic leukemia
Acute mountain sickness
Acute myelocytic leukemia
Acute myelogenous leukemia
Acute necrotizing...
Acute promyelocytic leukemia
Acute renal failure
Acute respiratory...
Acute tubular necrosis
Adams Nance syndrome
Adams-Oliver syndrome
Addison's disease
Adducted thumb syndrome...
Adenoid cystic carcinoma
Adenoma
Adenomyosis
Adenosine deaminase...
Adenosine monophosphate...
Adie syndrome
Adrenal incidentaloma
Adrenal insufficiency
Adrenocortical carcinoma
Adrenogenital syndrome
Adrenoleukodystrophy
Aerophobia
Agoraphobia
Agrizoophobia
Agyrophobia
Aicardi syndrome
Aichmophobia
AIDS
AIDS Dementia Complex
Ainhum
Albinism
Albright's hereditary...
Albuminurophobia
Alcaptonuria
Alcohol fetopathy
Alcoholic hepatitis
Alcoholic liver cirrhosis
Alektorophobia
Alexander disease
Alien hand syndrome
Alkaptonuria
Alliumphobia
Alopecia
Alopecia areata
Alopecia totalis
Alopecia universalis
Alpers disease
Alpha 1-antitrypsin...
Alpha-mannosidosis
Alport syndrome
Alternating hemiplegia
Alzheimer's disease
Amaurosis
Amblyopia
Ambras syndrome
Amelogenesis imperfecta
Amenorrhea
American trypanosomiasis
Amoebiasis
Amyloidosis
Amyotrophic lateral...
Anaphylaxis
Androgen insensitivity...
Anemia
Anemia, Diamond-Blackfan
Anemia, Pernicious
Anemia, Sideroblastic
Anemophobia
Anencephaly
Aneurysm
Aneurysm
Aneurysm of sinus of...
Angelman syndrome
Anguillulosis
Aniridia
Anisakiasis
Ankylosing spondylitis
Ankylostomiasis
Annular pancreas
Anorchidism
Anorexia nervosa
Anosmia
Anotia
Anthophobia
Anthrax disease
Antiphospholipid syndrome
Antisocial personality...
Antithrombin deficiency,...
Anton's syndrome
Aortic aneurysm
Aortic coarctation
Aortic dissection
Aortic valve stenosis
Apert syndrome
Aphthous stomatitis
Apiphobia
Aplastic anemia
Appendicitis
Apraxia
Arachnoiditis
Argininosuccinate...
Argininosuccinic aciduria
Argyria
Arnold-Chiari malformation
Arrhythmogenic right...
Arteriovenous malformation
Arteritis
Arthritis
Arthritis, Juvenile
Arthrogryposis
Arthrogryposis multiplex...
Asbestosis
Ascariasis
Aseptic meningitis
Asherman's syndrome
Aspartylglycosaminuria
Aspergillosis
Asphyxia neonatorum
Asthenia
Asthenia
Asthenophobia
Asthma
Astrocytoma
Ataxia telangiectasia
Atelectasis
Atelosteogenesis, type II
Atherosclerosis
Athetosis
Atopic Dermatitis
Atrial septal defect
Atrioventricular septal...
Atrophy
Attention Deficit...
Autoimmune hepatitis
Autoimmune...
Automysophobia
Autonomic dysfunction
Familial Alzheimer disease
Senescence
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
Medicines

It is a genetic disorder because the instructions to form the proteins for the enamel are encoded in the genes and are passed from generation to generation. New mutations are also possible.

Researchers have described at least 14 forms of amelogenesis imperfecta. These types are distinguished by their specific dental abnormalities and by their pattern of inheritance.

Features

Amelogenesis imperfecta presents with abnormal formation of the enamel or external layer of teeth. Enamel is composed mostly of mineral, that is formed and regulated by the proteins in it. AI is due to the malfunction of the proteins in the enamel: ameloblastin, enamelin, tuftelin and amelogenin.

People afflicted with amelogenesis imperfecta have teeth with abnormal colour: yellow, brown or grey. The teeth have a higher risk for cavities and are hypersensitive to temperature changes. This disorder can afflict any number of teeth.

Genetics

Up to date, mutations in the AMELX, ENAM MMP20and KLK-4 genes have been found to cause amelogenesis imperfecta (non-syndromic form). The AMELX, ENAM, KLK-4 and MMP20 genes provide instructions for making proteins that are essential for normal tooth development. These proteins are involved in the formation of enamel, which is a hard, calcium-rich material that forms the protective outer layer of each tooth. Mutations in any of these genes alter the structure of these proteins or prevent the genes from making any protein at all. As a result, tooth enamel is abnormally thin or soft and may have a yellow or brown color. Teeth with defective enamel are weak and easily damaged.

Researchers are looking for mutations in other genes that may also cause amelogenesis imperfecta.

Amelogenesis imperfecta can have different inheritance patterns depending on the gene that is altered. Most cases are caused by mutations in the ENAM gene and are inherited in an autosomal dominant pattern. This type of inheritance means one copy of the altered gene in each cell is sufficient to cause the disorder.

Amelogenesis imperfecta is also inherited in an autosomal recessive pattern; this form of the disorder can result from mutations in the ENAM or MMP20 gene. Autosomal recessive inheritance means two copies of the gene in each cell are altered.

About 5% of amelogenesis imperfecta cases are caused by mutations in the AMELX gene and are inherited in an X-linked pattern. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, one of the two sex chromosomes. In most cases, males with an X-linked form of this condition experience more severe dental abnormalities than affected females.

Read more at Wikipedia.org


[List your site here Free!]


Twenty-three years later and little has changed
From Dental Assistant, The, 5/1/04 by Mary K. Richter

The year was 1981. What began as a simple quest for information to help our family deal with the challenges of ectodermal dysplasia (ED) grew to become what is now the National Foundation for Ectodermal Dysplasias (NFED). At that time and to this day, I consider John R. Lintz, DDS, the dentist who initially diagnosed and provided dental care for our son, to be the epitome of the profession. I have great regard for dentists like him: those who provide quality care in a timely manner, dispense compassion and understanding in liberal doses, and work tirelessly for the well-being of the patient and the family.

The year was 1981. While our experiences with dentistry and dentures in a two-year-old were entirely positive, that was not always the case for other families. At that time, most children affected by ED syndromes went without dentures until their teenage years. It was believed that young children could not adapt to dentures. Furthermore, the cost of care was often prohibitive providing an excuse for delay of treatment. In 1981, it was not at all unusual for women with many missing teeth not to be questioned about the absence until they gave birth to sons who were fully affected by a type of ED, most often hypohidrotic ectodermal dysplasia.

Fast forward to now. A new millennium has officially arrived. Here at the NFED we are celebrating some remarkable successes. Included among them are our Treatment Fund, which provides financial assistance for oral health care, and a dental implant program. Also, we have significantly impacted both the age of diagnosis and age of first treatment and spearheaded legislative efforts that are improving insurance coverage. I wish, however, that I could report that all of the problems faced in 1981 have been resolved. How nice it would be for all children affected by ED syndromes to have a functioning and esthetically pleasing dentition. But calls to our office indicate that such is not the case. The excuses provided by members of the dental professions are often pitiful. "He'll look fine with just his two teeth if we bond them." "Let's wait with dentures until she's fully grown." "The cost of care will be $50,000--we need half upfront and the remainder when the work is complete." How I yearn for all of these children to have the type of dentist who cared for our child. How I wish they could all experience the positive impact of a complete dentition at an early age. And women with many missing teeth continue to remain undiagnosed because no one cared enough to question their missing teeth. Their anger resonates in our office following the birth of children with similar problems that are diagnosed shortly thereafter.

Fast forward to 2004. Financial barriers to care still exist. With virtually no improvement in Medicaid reimbursement and no tidal wave of support for the dental effects of birth defects to be covered under medical insurance, patients go without care. While there has been much excitement in dentistry since the issuance of the Surgeon General's Report on Oral Health, where is the excitement for the special care patients, those needing something beyond routine care? When will the oral health needs of children and adults affected by conditions like amelogenesis imperfecta, ED, and Reiger's syndrome become a priority? When will dentists faced with providing care for these individuals be educated to provide that care effectively? When will dentistry become a partner for these patients rather than a stumbling block? The questions from 1981 are still there. When will there be answers?

COPYRIGHT 2004 American Dental Assistants Association
COPYRIGHT 2004 Gale Group

Return to Amelogenesis imperfecta
Home Contact Resources Exchange Links ebay