Dentin Dysplasia Type I

National Organization for Rare Disorders, Inc.

Skip to the navigation


It is possible that the main title of the report Dentin Dysplasia Type I is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.


  • Dentin Dysplasia, Radicular
  • Opalescent Dentin
  • Radicular Dentin Dysplasia
  • Rootless Teeth
  • Pulpless Teeth
  • Thistle Tube Teeth

Disorder Subdivisions

  • None

General Discussion

Dentin dysplasia type I is an inherited disorder characterized by atypical development of the "dentin" of a person's teeth. Dentin makes up most of the tooth and is the bone-like material under the enamel. It serves to contain the pulp of the tooth. The pulp is a soft tissue that is well supplied with blood vessels and nerves. This disorder is also known as radicular dentin dysplasia because the underdeveloped, abnormal pulp tissue is predominately in the roots of the teeth. The teeth lack pulp chambers or have half-moon shaped pulp chambers in short or abnormally shaped roots. The condition may affect juvenile as well as adult teeth and, since the roots are abnormally short, usually leads to the premature loss of teeth. The color of the teeth is usually normal.


Some people with dentin dysplasia type I have teeth with a bluish-brown shine. In most instances, however, the teeth have normally colored enamel. It is clear from X-ray photos that the tooth pulp chambers in the roots are unusually small, half-moon shaped or lacking altogether. The roots are very short and may appear to be dark (radiolucent) on X-rays.

Both the baby teeth and the permanent teeth are affected. The teeth are often poorly aligned and can be chipped easily. Without treatment, persons with dentin dysplasia type I may lose their teeth by age 30-40.


Dentin dysplasia is inherited as an autosomal dominant trait. The defective gene has not been identified or traced to a particular site on a particular chromosome.

Chromosomes, which are present in the nucleus of human cells, carry the genetic information for each individual. Human body cells normally have 46 chromosomes. Pairs of human chromosomes are numbered from 1 through 22 and the sex chromosomes are designated X and Y. Males have one X and one Y chromosome and females have two X chromosomes. Each chromosome has a short arm designated "p" and a long arm designated "q". Chromosomes are further sub-divided into many bands that are numbered. For example, "chromosome 11p13" refers to band 13 on the short arm of chromosome 11. The numbered bands specify the location of the thousands of genes that are present on each chromosome.

Genetic diseases are determined by the combination of genes for a particular trait that are on the chromosomes received from the father and the mother.

Dominant genetic disorders occur when only a single copy of an abnormal gene is necessary for the appearance of the disease. The abnormal gene can be inherited from either parent, or can be the result of a new mutation (gene change) in the affected individual. The risk of passing the abnormal gene from affected parent to offspring is 50% for each pregnancy regardless of the sex of the resulting child.

Recessive genetic disorders occur when an individual inherits the same abnormal gene for the same trait from each parent. If an individual receives one normal gene and one gene for the disease, the person will be a carrier for the disease, but usually will not show symptoms. The risk for two carrier parents to both pass the defective gene and, therefore, have an affected child is 25% with each pregnancy. The risk to have a child who is a carrier like the parents is 50% with each pregnancy. The chance for a child to receive normal genes from both parents and be genetically normal for that particular trait is 25%. The risk is the same for males and females.

All individuals carry 4-5 abnormal genes. Parents who are close relatives (consanguineous) have a higher chance than unrelated parents to both carry the same abnormal gene, which increases the risk to have children with a recessive genetic disorder.

Affected Populations

Dentin dysplasia type I appears to affect about 1 in 100,000 persons. Males and females are apparently equally at risk.

Standard Therapies


Diagnosis is usually based on x-rays taken when some abnormality is suspected.


The affected teeth are usually treated by a dentist specializing in the care of the roots and pulp of the teeth (endodontists). Filling the tips of the root canals may extend the period of time that the affected teeth remain fixed to the jaw. Sometimes, the affected teeth must be extracted and replaced with dentures.

Genetic counseling is recommended for families of children with dentin dysplasia type I.

Investigational Therapies

Information on current clinical trials is posted on the Internet at All studies receiving U.S. government funding, and some supported by private industry, are posted on this government website.

For information about clinical trials being conducted at the National Institutes of Health (NIH) in Bethesda, MD, contact the NIH Patient Recruitment Office:

Tollfree: (800) 411-1222

TTY: (866) 411-1010


For information about clinical trials sponsored by private sources, contact:



Brenneise CV. Dentin Dysplasia. In: NORD Guide to Rare Disorders. Lippincott Williams & Wilkins. Philadelphia, PA. 2003:176-77.


Hegde M, Hegde ND. Dentin dysplasia - A case report. Endontol. 2004;16:16-18.

Seymen F, Akinci T. Dentinal Dysplasia Type I: Report of a case. Eur J Paediatr Dent. 2000;1:Abstract 71.

Leccisotti S, Eramo S, Palatella P, et al. Dentin dysplasia type I. Report of a case and ultrastructural study. Minerva Stomatol. 1998;47:545-51.

Brenneise CV, Dwornick RM, Benneise EE. Clinical radiographic and histological manifestations of dentin dysplasia, type I: report of a case. J Am Dent Assoc. 1989;119:721-23.

Witkop CJ Jr. Amelogenesis imperfecta, dentinogenesis imperfecta and dentition dysplasia revisited: problems in classification. J Oral Pathol. 1988;17:547-53.

Petrone JA, Noble ER. Dentin dysplasia type I: a clinical report. J Am Dent Assoc. 1981;103:891-93.


McKusick VA, ed. Online Mendelian Inheritance In Man (OMIM). The Johns Hopkins University. Dentin Dysplasia, Type I. Entry Number; 125400: Last Edit Date; 3/18/2004.

McKusick VA, ed. Online Mendelian Inheritance In Man (OMIM). The Johns Hopkins University. Dentin Dysplasia, Type II. Entry Number; 125420: Last Edit Date; 2/3/2004.

McKusick VA, ed. Online Mendelian Inheritance In Man (OMIM). The Johns Hopkins University. Dentin Dysplasia with Sclerotic Bones. Entry Number; 125440: Last Edit Date; 3/18/2004.

Sedano HO. Abnormalities in Structure of Teeth. Oral Pathology I (DS482A). nd. 9pp.

Sedano HO. Premature Loss of Teeth. Periodontics Information Center. ©1998. 4pp.

How exactly are various parts of the body affected by ED syndromes and what treatments are available? Teeth. National Foundation for Ectodermal Dysplasia. NFED. nd. 2pp.


March of Dimes Birth Defects Foundation

1275 Mamaroneck Avenue

White Plains, NY 10605

Tel: (914)997-4488

Fax: (914)997-4763


NIH/National Institute of Dental and Craniofacial Research

Building 31, Room 2C39

31 Center Drive, MSC 2290

Bethesda, MD 20892


Tel: (301)496-4261

Fax: (301)480-4098

Tel: (866)232-4528



Genetic and Rare Diseases (GARD) Information Center

PO Box 8126

Gaithersburg, MD 20898-8126

Tel: (301)251-4925

Fax: (301)251-4911

Tel: (888)205-2311

TDD: (888)205-3223


For a Complete Report

This is an abstract of a report from the National Organization for Rare Disorders, Inc.® (NORD). Cigna members can access the complete report by logging into For non-Cigna members, a copy of the complete report can be obtained for a small fee by visiting the NORD website. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational treatments (if available), and references from medical literature. For a full-text version of this topic, see