Anodontia

Disease Overview

Anodontia is a genetic disorder defined as the absence of all teeth (teeth agenesis). It usually occurs as part of a syndrome that includes other abnormalities.  

Other conditions characterized by tooth agenesis are hypodontia and oligodontia, which are more common than anodontia. Hypodontia is genetic in origin and usually involves the absence of from 1 to 5 teeth. Oligodontia is genetic as well and is the term used to describe a condition in which 6 or more teeth are missing. 

Hypodontia/oligodontia/anodontia might be considered as a unique clinical entity, meaning it’s the same basic problem – missing teeth, but each is with increasing severity. 

These conditions may involve either the primary or permanent sets of teeth, but most cases involve the permanent teeth.  

Tooth agenesis (the absence of one or more teeth) occurs following a specific pattern of missing teeth. Not only the number of missing teeth, but also the type of missing teeth, must be considered. 

Tooth agenesis is often associated with a group of conditions affecting the development or function of the teeth, hair, nails and sweat glands called ectodermal dysplasias. 

• View Full Report Show Less
• Print / Download as PDF

• Next section >

• < Previous section
• Next section >

Subdivisions

• Hypodontia (absence of 1-5 teeth)
• Oligodontia (absence of 6 or more teeth)
• Anodontia (absence of all teeth)

• < Previous section
• Next section >

• < Previous section
• Next section >

Signs & Symptoms

Anodontia is characterized by complete absence of teeth. Since all primary teeth are usually present by the age of three, their absence is usually noted, and a dentist is consulted.  

Except for wisdom teeth, all permanent teeth are usually present by the ages 12 to 14. When teeth have not appeared by the appropriate age, dental panoramic X-rays are usually taken. 

When anodontia and also hypo/oligodontia occur, abnormalities of hair, nails, and sweat glands may also be present. In many cases, hypo/oligodontia is a component of one of the ectodermal dysplasias, a group of hereditary disorders. 

• < Previous section
• Next section >

• < Previous section
• Next section >

Causes

Anodontia and other types of tooth agenesis can occur as part of a broader medical condition (syndromic cases) or in individuals who are otherwise healthy (isolated cases). Because many of the same genes are involved in both situations, there is no strict genetic boundary between syndromic and isolated cases.  

Many genes have been associated to isolated and/or syndromic hypo/oligodontia: 

ADAMTS2, ANOS1, ANTXR1, ATP6V1B2, AXIN2, BCOR, BLM, BMP2, BMP4, CDH3, COL17A1, COL1A1, COL1A2, COL3A1, CREB3L1, CREBBP, CTNNB1, CXORF5, DKK1, DSP, DTDST, EDA, EDAR, EDARADD, ETV6, EVC1, EVC2, EYA1, FAM20A, FGF10, FGFR1, FGFR2, FGFR3, FLNB, FOXC1, GJA1, GJB6, GLI3, GREM2, GRHL2, GRHL3, HOXB1, HRAS, IFT122, IFT43, IKBKG, IKKγ, IRF6, JAG1, KCTD1, KDF1, KDM6A, KMT2D,KREMEN1, LAMA3, LAMB3, LEF1, LRP4, LRP6, LTBP3, MEGF8, MKKS, MSX1, NECTIN4=PVRL4, NSD1, OFD1, P63, PAX3, PAX9, PHGDH, PITX2, PKP1, POC1A, POLR1D, POLR1C, POLR3A, POLR3B, POLR3GL, PORCN, PROK2, PROKR2, PVRL1, PVR4, RAB23, RECQL4, RNF216, RPS6KA3, RSK2, RUNX2, SATB2, SHH, SLC26A2, SLC29A3, SMOC2, SPECC1L, TBCE, TBX3, TBX22, TCOF1, TFAP2B, TP63, TSPEAR, UBR1, WDR19, WDR35, WNT10A, WNT10B. 

Research consistently highlights four major genes that play key roles in tooth development: EDA, MSX1, WNT10A, and PAX9. Changes in these genes (gene variants) can influence how many teeth are missing and which ones are affected. For example: 

• EDA gene variants often impact the front teeth and may be associated with a condition known as X-linked hypohidrotic ectodermal dysplasia.  

• MSX1 gene variants can contribute to missing teeth and may also be linked with certain facial differences.  

• The WNT10A gene variant is the most common cause of isolated (not part of a broader syndrome affecting other body systems) hypodontia (missing 1-5 teeth) and oligodontia (missing 6 or more teeth).  

• PAX9 gene variants are strongly tied to molar development. 

Some people are born missing certain teeth, and this often follows recognizable patterns. Different genes help guide how teeth form in early development. When a gene doesn’t work as expected, a person may have fewer teeth, or teeth that are smaller or shaped differently. LRP6, KREMEN1, PITX2, SMOC2, SHH, GREM2, and TSPEAR all help regulate the signaling pathways that guide early tooth formation. When these pathways are disrupted, tooth size, shape, or number can change. For example:  

• LRP6 and KREMEN1 gene variants often affect the front teeth. 

• PITX2 variants are usually linked to more severe tooth loss. 

• SMOC2 variants commonly involve missing second premolars. 

• SHH variants often affect the midline and may lead to a single front tooth (central incisor) in the center. 

• GREM2 variants affect the signaling pathway important for early tooth development (bone morphogenetic protein [BMP]) and can lead to missing multiple teeth, often in a recognizable pattern. 

• TSPEAR variants are tied to recessive forms of oligodontia (many missing teeth). 

• A rare AXIN2 variant can cause tooth agenesis and increase colorectal cancer risk. 

Clinical studies show that the underlying gene change (variant) often matches the pattern seen in the mouth. When tooth agenesis is part of a genetic syndrome, people may also have differences in the skin, hair, nails, or sweat glands. Even isolated cases (when the tooth loss is not part of a broader syndrome affecting other body systems) when teeth are the only concern, missing teeth can influence facial shape and growth, including the width of the upper jaw or the position of the chin. Dentists use exams and radiographs (X-rays) to diagnosis the condition, and early treatment with functional dental appliances or prosthetic teeth can support more balanced jaw development and support normal chewing and speech (oral function). 

Tooth agenesis (hypodontia or oligodontia) might also be associated with cleft lip and palate in certain syndromes. A rare association was discovered linking tooth agenesis and susceptibility to colorectal cancer (AXIN2 gene variants). 

OMIM have a table with different types of tooth agenesis with their specific associated genes. OMIM (Online Mendelian Inheritance in Man), is a free, comprehensive, and continuously updated database of human genes and genetic disorders.  

Each person has two copies of every gene – one from each parent. How a genetic condition is passed down depends on which gene from which parent is affected and how that gene works.  

• Autosomal recessive: A person must inherit two non-working copies of the gene (one from each parent) to have the condition. Parents usually have no symptoms but are carriers. Two carriers have a:  

• 25% chance of having an affected child with each pregnancy 

• 50% chance of having a carrier child with each pregnancy 

• 25% of having a child with no variant 

• These chances are the same for males and females. Parents who are related by blood (consanguineous) have a higher chance than unrelated parents of carrying the same gene change, which increases the risk of having children with a recessive genetic disorder.  

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

• Autosomal dominant: A single non-working gene copy is enough to cause the condition. The non-working gene can be inherited from either parent. An affected parent has a 50% chance of passing it on with each pregnancy. The risk is the same for males and females. 

• De novo (new) variants: Sometimes, the gene change happens for the first time in the egg or sperm cell. In such situations, the disorder was not inherited from either parent. 

• X-linked inheritance (recessive and dominant): Some genetic conditions are caused by a non-working gene on the X chromosome. Because males and females inherit X chromosomes differently, how the condition appears may vary.  

• X-linked recessive conditions: In X-linked recessive conditions, the gene change causes symptoms mainly in males. This is because males have only one X chromosome, which they receive from their mother. If the X chromosome has a non-working gene, the male will show symptoms.  

Females have two X chromosomes. If one X chromosome has a non-working gene, the other X chromosome usually compensates. These females are typically carriers and usually do not show symptoms.  

Female carriers of an X-linked disorder have a:  

• 25% chance with each pregnancy to have a carrier daughter like themselves with each pregnancy 

• 25% chance to have a non-carrier daughter with each pregnancy 

• 25% chance to have a son affected with the disease with each pregnancy 

• 25% chance to have an unaffected son with each pregnancy 

An affected male will:  

• pass the non-working gene to all his daughters (They will become carriers.) 

• pass no non-working gene to his sons (He gives them a Y chromosome.) 

• X-linked dominant conditions: In X-linked dominant conditions, one non-working gene on the X chromosome is enough to cause symptoms.  

• Females with one non-working gene on the X chromosome will show symptoms because the non-working copy is strong enough to cause the condition (even with one working copy).  

• Males with the non-working gene are usually more severely affected because they have no second X chromosome to offset the change. 

An affected male will:  

• pass the condition to all daughters. 

• pass the condition to no sons (He gives them a Y chromosome.) 

Both X-linked recessive and X-linked dominant inheritance can occur in conditions involving oral and dental (orodental) genes, depending on which gene is affected. X-linked disorders do not all follow the same rules. It is important for families to understand the inheritance patter (X-linked recessive or X-linked dominant). 

• < Previous section
• Next section >

• < Previous section
• Next section >

Affected populations

The prevalence of anodontia (being born without any teeth) is unknown, although the condition is extremely rare and most often appears as part of an associated syndrome. It affects males and females equally. Hypodontia (missing a few teeth) is much more common. It affects about 2-8% of people, not county wisdom teeth (third molar). Oligodontia (missing many teeth) is less common but still seen in the general population. Based on current estimates, about 359,000 to 461,000 people in the US may have oligodontia, based on the 0.14% prevalence estimate for Caucasian populations in North America and a US population of approximately 331 million people. 

• < Previous section
• Next section >

• < Previous section
• Next section >

Disorders with Similar Symptoms

It is important for dentists and doctors to tell the difference between isolated cases of anodontia and other forms of tooth agenesis (missing teeth) and cases that are part of the ectodermal dysplasias. Ectodermal dysplasias are inherited non-progressive conditions that affect several body structures that come from the same early tissue layer – such as teeth, hair, nails and sweat glands, salivary glands, mammary (milk) glands within breast tissue, and tear (nasolacrimal) ducts.  

• < Previous section
• Next section >

• < Previous section
• Next section >

Diagnosis

Anodontia is diagnosed through a dental exam and X-rays, which confirm that the permanent teeth have not formed or are missing even after the age when they should have come in. Hypodontia and oligodontia (missing a few or many teeth) are also diagnosed this way.  

People with missing teeth should also have a full physical exam to check for signs outside the mouth that might suggest a genetic syndrome. A detailed dental evaluation and review of past and current X-rays is then used to identify exactly which teeth are missing and to look for other dental differences. Common findings include:  

• Small teeth (microdontia) 

• Unusual tooth shapes, such as peg-shaped lateral incisors 

• Bite problems (malocclusion) 

• Space or gaps between teeth (spaced dentition) 

• Baby (primary) teeth that remain longer than expected 

Genetic testing is available to identify variants in 560 known and candidate genes involved in oral and dental (orodental) diseases. 

• < Previous section
• Next section >

• < Previous section
• Next section >

Standard Therapies

Treatment 

Treatment for anodontia and other types of tooth agenesis (hypodontia and oligodontia), focuses on restoring function (chewing, speech), appearance, and long-term oral health. Options range from removable dentures to orthodontic, surgical and implant-based solutions. The approach depends on how many teeth are missing and the person’s age.  

For young children (as early as 3-4 years old):  

• Removable dentures or partial dentures (removable prostheses) can be used and updated as the child grows.  

• If only a few front teeth are missing, temporary options like bonded acrylic teeth may be used.  

For older teens and adults, dental implants or fixed bridges may be considered once growth is complete and bone support allows.  

Planning treatment for dental agenesis requires careful evaluation of smile aesthetics, jaw growth, tooth shape, and available space. For example, when upper (maxillary) lateral incisors are missing, specialists may choose either to close the space and reshape nearby teeth (often preferred in children), or to keep open space for future implants or prosthetic teeth (often suitable for adults).  

Because implants cannot be placed until after jaw growth is complete and because maintaining implant spaces can lead to bone resorption (bone loss) over time, treatment plans can change over time as a person ages. No matter the approach, orthodontic retention (such as wearing a retainer) is important to keep the teeth from shifting.  

In more complex cases with multiple missing teeth, treatment may include combinations of:  

• Jaw (maxillary) expansion 

• Removable partial dentures 

• Careful space management 

• Restorative dentistry to help with speech, chewing, and balanced facial growth. 

Management of dental agenesis is individualized and often requires a team of several specialists that should work together in a coordinated way, including:  

• Pediatric dentists 

• Orthodontists 

• Prosthodontists 

• Oral and maxillofacial surgeons 

• Genetic specialists (when needed) 

Early diagnosis is key to plan long-term care, monitor facial development, and choose the right treatment through different stages of growth. Collaboration among specialists (coordinated care) helps improve and keep stable function, appearance, and overall quality of life for people with mild or extensive tooth absences (missing teeth). 

• < Previous section
• Next section >

• < Previous section
• Next section >

Clinical Trials and Studies

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

For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:

Tollfree: (800) 411-1222
TTY: (866) 411-1010
Email: [email protected]

Some current clinical trials also are posted on the following page on the NORD website:
https://rarediseases.org/for-patients-and-families/information-resources/info-clinical-trials-and-research-studies/

For information about clinical trials sponsored by private sources, contact:
https://www.centerwatch.com/

For information about clinical trials conducted in Europe, contact:
https://www.clinicaltrialsregister.eu/

• < Previous section
• Next section >

• < Previous section
• Next section >

References

TEXTBOOK
Rey T, et al Bloch-Zupan Protocol GenoDENT: implementation of a new NGS panel for molecular diagnosis of genetic disorders with orodental involvement. In Papagerakis P (ed). Odontogenesis. Methods and protocols. Springer. New York. 2019. 

Bloch-Zupan A, Sedano H, Scully C. 2012. Dento/oro/craniofacial anomalies and genetics: 1st edn. Boston, MA: Elsevier. 

Jones KL. Ed. Smith’s Recognizable Patterns of Human Malformation. 5th ed. W. B. Saunders Co., Philadelphia, PA; 1997:801. 

JOURNAL ARTICLES
Fournier BP, Bruneau MH, Toupenay S, Kerner S, Berdal A, Cormier-Daire V, Hadj-Rabia S, Coudert AE, de La Dure-Molla M. Patterns of Dental Agenesis Highlight the Nature of the Causative Mutated Genes. J Dent Res. 2018 Nov;97(12):1306-1316. 

Juuri E, Balic A. The Biology Underlying Abnormalities of Tooth Number in Humans.
J Dent Res. 2017 Oct;96(11):1248-1256. 

Savasta S, Carlone G, Castagnoli R, et al. X-linked hypohidrotic ectodermal dysplasia: new features and a novel EDA gene mutation. Cytogenet Genome Res. 2017;152(3):111-116. doi: 10.1159/000478922. Epub 2017 Sep 7. 

Tardieu C, Jung S, Niederreither K, Prasad M, Hadj-Rabia S, Philip N, Mallet A, Consolino E, Sfeir E, Noueiri B, Chassaing N, Dollfus H, Manière MC, Bloch-Zupan A, Clauss F. Dental and extra-oral clinical features in 41 patients with WNT10A gene mutations: A multicentric genotype-phenotype study. Clin Genet. 2017 Nov;92(5):477-486. doi: 10.1111/cge.12972. Epub 2017 Mar 19. 

Bergendal B. Orodental manifestations in ectodermal dysplasia-a review.
Am J Med Genet A. 2014 Oct;164A(10):2465-71. 

Klineberg I, Cameron A, Whittle T, Hobkirk J, Bergendal B, Maniere MC, King N, Palmer R, Hobson R, Stanford C, Kurtz K, Sharma A, Guckes A. Rehabilitation of children with ectodermal dysplasia. Part 1: an international Delphi study. Int J Oral Maxillofac Implants. 2013 Jul-Aug;28(4):1090-100. 

Klineberg I, Cameron A, Hobkirk J, Bergendal B, Maniere MC, King N, Watkins S, Hobson R, Stanford C, Kurtz K, Sharma A. Rehabilitation of children with ectodermal dysplasia. Part 2: an international consensus meeting. Int J Oral Maxillofac Implants. 2013 Jul-Aug;28(4):1101-9. 

Salinas TJ, Sheridan PJ, Castellon P, et al. Treatment planning for multiunit restoration – the use of diagnostic planning to predict implant and esthetic results inpatients with congenitally missing teeth. J Oral Maxillofac Surg. 2005;63(9 Suppl 2):45-58. 

Larmour CJ, Mossey PA, Thind BS, et al. Hypodontia – a retrospective review of prevalence and etiology. Part I. Quintessence Int. 2005;36:263-70. 

Mostowska A, Kobielak A, Trzeciak WH. Molecular basis of non-syndromic tooth agenesis: mutations of MSX1 and PAX9 reflect their role in patterning human dentition. Eur J Oral Sci. 2003;111:365-70. 

Jepson NJ, Nohl FS, Carter NE, et al. The interdisciplinary management of hypodontia: restorative dentistry. Br Dent J. 2003;194:299-304. 

Nunn JH, Carter NE, Gillgrass TJ, et al. The interdisciplinary management of hypodontia: background and role of paediatric dentistry. Br Dent J. 2003;194:245-51. 

Ruhin B, Martinot V, Lafforgue P, et al. Pure ectodermal dysplasia: retrospective study of 16 cases and literature review. Cleft Palate Craniofac. 2001;38:504-18. 

INTERNET
Anodontia. Genetic and Rare Diseases Information Center. Last updated: Feb 2023. https://rarediseases.info.nih.gov/diseases/5818/anodontia Accessed June 9, 2023. 

Anodontia. Orphanet. Last update: October 16, 2025. https://www.orpha.net/consor/cgi-bin/Disease_Search.php?lng=EN&data_id=14370&Disease_Disease_Search_diseaseGroup=anodontia&Disease_Disease_Search_diseaseType=Pat&Disease(s)/group%20of%=Anodontia&title=Anodontia&search=Disease_Search_Simple Accessed November 24, 2025.  

Oligodontia. Orphanet. Last update: January, 2013.
https://www.orpha.net/consor4.01/www/cgi-bin/Disease_Search.php?lng=EN&data_id=14371&Disease_Disease_Search_diseaseGroup=oligodontia&Disease_Disease_Search_diseaseType=Pat&Disease(s)/group%20of%20diseases=Oligodontia&title=Oligodontia&search=Disease_Search_Simple
Accessed November 24, 2025. 

Modafferi C, Tucci I, Bogliardi FM, et al. Genetic Aspects of Tooth Agenesis. Genes (Basel). 2025;16(5):582. Published 2025 May 15. doi:10.3390/genes16050582 

Zhou M, Zhang H, Camhi H, et al. Analyses of oligodontia phenotypes and genetic etiologies. Int J Oral Sci. 2021;13(1):32. Published 2021 Sep 30. doi:10.1038/s41368-021-00135-3 

Letra A, Chiquet B, Hansen-Kiss E, et al. Nonsyndromic Tooth Agenesis Overview. 2021 Jul 22. In: Adam MP, Bick S, Mirzaa GM, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2025. Available from: https://www.ncbi.nlm.nih.gov/books/NBK572295/ 

• < Previous section
• Next section >

• < Previous section

Programs & Resources

• Assistance Programs
• Patient Organizations

RareCare^® Assistance Programs

NORD strives to open new assistance programs as funding allows. If we don’t have a program for you now, please continue to check back with us.

Additional Assistance Programs

MedicAlert Assistance Program

NORD and MedicAlert Foundation have teamed up on a new program to provide protection to rare disease patients in emergency situations.

Learn more https://rarediseases.org/patient-assistance-programs/medicalert-assistance-program/

Rare Disease Educational Support Program

Ensuring that patients and caregivers are armed with the tools they need to live their best lives while managing their rare condition is a vital part of NORD’s mission.

Learn more https://rarediseases.org/patient-assistance-programs/rare-disease-educational-support/

Rare Caregiver Respite Program

This first-of-its-kind assistance program is designed for caregivers of a child or adult diagnosed with a rare disorder.

Learn more https://rarediseases.org/patient-assistance-programs/caregiver-respite/

Learn more about Patient Assistance Programs >

• < Previous section