trichodontoosseous syndrome

Tricho-dento-osseous Syndrome (TDO): A Rare Genetic Disorder

Tricho-dento-osseous syndrome, also known as TDO syndrome, is a rare genetic disorder that affects the development of hair, teeth, and bones. This autosomal dominant condition is characterized by a range of symptoms, including:

• Curly or kinky hair: One of the most distinctive features of TDO syndrome is curly or kinky hair at birth, which may straighten out with age.
• Enamel hypoplasia: Defects in tooth enamel, leading to discoloration and other abnormalities.
• Molar taurodontism: A condition where the molars have a larger pulp chamber and smaller roots.
• Increased bone mineral density (BMD): Higher than normal BMD, which can lead to thicker cortical bones of the skull.
• Dysplastic nails: Abnormal development of the nails.

TDO syndrome is caused by mutations in the DLX3 gene on chromosome 17q21. The condition is inherited in an autosomal dominant pattern, meaning that a single copy of the mutated gene is enough to cause the disorder.

References:

• [1] Tricho-dento-osseous dysplasia (TDO) belongs to the ectodermal dysplasias and is characterised by curly/kinky hair at birth, enamel hypoplasia with discolouration and molar taurodontism, increased overall bone mineral density (BMD) and increased thickness of the cortical bones of the skull. [2]
• Tricho-dento-osseous syndrome (TDO) is an autosomal dominant disorder with a range of dental and non-dental findings such as taurodontism, amelogenesis imperfecta, osseous dysplasia, mandibular prognathism, curly hair, dysplastic nails. [10]
• Tricho-dento-osseous syndrome (TDO) is caused by heterozygous mutation in the DLX3 gene (600525) on chromosome 17q21. [11]

Tricho-dento-osseous (TDO) syndrome is a rare genetic disorder that affects the development of ectodermal structures, such as hair, nails, and teeth, as well as mesenchymal structures, like bones.

Common Signs and Symptoms:

• Abnormalities in hair, including curly or kinky hair at birth [5]
• Enamel hypoplasia (underdeveloped enamel) and hypomineralization (reduced mineral content) of the teeth [2, 9]
• Small, widely spaced teeth [3]
• Thin and/or pitted enamel [3]
• Enlarged pulp chambers and taurodontism (a condition where the pulp chamber is enlarged and the roots are short) [3]
• Periapical abscesses (collections of pus) around the teeth [3]
• Hair and bone abnormalities [4, 6]
• Oral abnormalities, including delayed tooth eruption and teeth discoloration [8]

Other Features:

• Sclerotic bones (increased bone density) [7]
• Malformed nails [9]

It's worth noting that the severity and presentation of TDO syndrome can vary among affected individuals.

Diagnostic Tests for Tricho-dento-osseous Syndrome

Tricho-dento-osseous (TDO) syndrome is a rare genetic disorder that can be diagnosed through various diagnostic tests. Here are some of the key tests used to diagnose TDO syndrome:

• Genetic Testing: Genetic testing is a crucial step in diagnosing TDO syndrome. It involves analyzing the DNA of suspected patients for mutations or deletions in the DLX3 gene, which is responsible for the condition [1][2]. This test can confirm the presence of the disease and rule out other conditions.
• Radiographic Imaging: Radiographic imaging, such as X-rays or CT scans, can help diagnose TDO syndrome by revealing characteristic features like taurodontism (enlarged pulp chambers) and sclerotic bone [3][4].
• Electron Microscopy: Electron microscopy of tooth enamel can reveal an abnormally thin enamel layer with scattered, random pits, which is a hallmark of TDO syndrome [5].
• Clinical Examination: A thorough clinical examination by a physician can also help diagnose TDO syndrome. This involves looking for characteristic physical features like abnormal teeth, nails, and hair [6].

Other Diagnostic Tests

In addition to the above tests, other diagnostic tests may be used to rule out other conditions or to confirm the diagnosis of TDO syndrome. These include:

• Clinical Trials: Clinical trials may be conducted to determine the effectiveness and safety of new diagnostic tests or treatments for TDO syndrome [7].
• Observational Studies: Observational studies can provide valuable information on the natural history of TDO syndrome and help identify potential biomarkers for diagnosis [8].

References

[1] GARD Disease Summary. The Genetic and Rare Diseases Information Center (GARD) has information and resources for patients, caregivers, and families that may be helpful before and after diagnosis of this condition.

[2] Al-Batayneh OB. For diagnostic purposes, genetic testing aims to test the DNA of suspected patients for the presence of a DLX3 deletion using PCR amplification.

[3] Tricho-dento-osseous (TDO) syndrome is a rare, autosomal dominant disorder principally characterised by curly hair at infancy, severe enamel hypomineralization and hypoplasia and taurodontism of teeth, sclerotic bone, and other defects.

[4] Diagnostic criteria are based on the generalized enamel defects …

[5] Electron microscopy of tooth enamel can reveal an abnormally thin enamel layer with scattered, random pits, which is a hallmark of TDO syndrome.

[6] A thorough clinical examination by a physician can also help diagnose TDO syndrome. This involves looking for characteristic physical features like abnormal teeth, nails, and hair.

[7] Clinical trials determine if a new test or treatment for a disease is effective and safe by comparing groups receiving different tests/treatments.

[8] Observational studies involve recording changes over time among a specific group of people in their natural settings.

Tricho-dento-osseous (TDO) syndrome is a rare, autosomal dominant disorder that affects the development of teeth, bones, and hair. While there is no specific "drug treatment" for TDO syndrome, various dental treatments can help manage its symptoms.

Dental Treatments

• Frequent Dental Cleanings: Regular cleanings can help prevent problems such as sensitivity, caries, and dental abscesses [7].
• Desensitizing Medication: Professional application of desensitizing medication can help alleviate tooth sensitivity [7].
• Root Canal Treatment: In cases where teeth are affected by taurodontism or other abnormalities, root canal treatment may be necessary to prevent infection [15].

Preventive Maintenance Therapy

• Regular Check-ups: Regular dental check-ups can help identify potential problems early on and allow for prompt intervention.
• Dietary Counseling: A balanced diet that is low in sugar and acid can help prevent tooth decay and other oral health issues.

It's essential to note that TDO syndrome requires a team approach, proper documentation, and long-term treatment and follow-up [11]. A multidisciplinary team of healthcare professionals, including dentists, orthodontists, and genetic counselors, may be necessary to manage the condition effectively.

References

• [7] Preventive maintenance therapy for the oral effects of TDO involve frequent dental cleanings, professional application of desensitizing medication, diet ...
• [11] Management of TDO requires a team approach, proper documentation, and a long-term treatment and follow-up plan.
• [15] by F Nejatidanesh · 2021 · Cited by 3 — Repeated irrigation with 2.5% sodium hypochlorite, and the use of ultrasonic irrigation. Using a combination of root canal filling techniques: lateral ...

The differential diagnosis for tricho-dento-osseous (TDO) syndrome involves considering other conditions that may present with similar symptoms. Some of these conditions include:

• Amelogenesis imperfecta: a group of genetic conditions characterized by underdeveloped or hypomineralized tooth enamel [2].
• Osteopetrosis: a rare, autosomal dominant disorder characterized by increased bone density and can be associated with dental abnormalities [7].
• Hypomaturation-hypoplastic type amelogenesis imperfecta (AIHHT): a condition that affects the development of tooth enamel, leading to thin, pitted, or mottled teeth [11].
• Oculodentoosseous dysplasia: a rare genetic disorder affecting the eyes, teeth, and bones [10].

These conditions can be ruled out through a combination of clinical evaluation, radiographic examination, and laboratory tests.