Hypodontia
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At the time the article was created Henry Knipe had no recorded disclosures.
View Henry Knipe's current disclosuresAt the time the article was last revised Daniel J Bell had no financial relationships to ineligible companies to disclose.
View Daniel J Bell's current disclosures- Oligodontia
- Adontia
- Congenitally missing teeth
Hypodontia, also known as oligodontia or adontia, refers to the developmental failure of one or more teeth, excluding the third molars.
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Terminology
The phenomenon of non-development of teeth has been described using several terms including 'hypodontia', 'oligodontia' and 'adontia'. The descriptor 'congenitally missing teeth' has also been used, but may be misleading as teeth development is completed following birth so identification is only possible in early childhood.
Epidemiology
Hypodontia is common, affecting between 1.6 to 6.9% of the population with a recognized variations in ethnicities. There is a female preponderance with a M:F of 2:3 1,2.
Pathology
Hypodontia is relatively rare in the primary dentition, mostly affecting the secondary dentition. The maxillary lateral incisors or mandibular premolars are most commonly missing, and in most individuals only one or two teeth are absent . Hypodontia is also associated with microdontia and delayed dental development 1,2.
Absence of one or more of the third molars affects around 20% of the population and is considered part of normal variation rather than hypodontia.
Hypodontia is known to occur with a large range of syndromes including cleft lip and palate, Down syndrome and ectodermal dysplasia, but is also common in non-syndromic patients 1.
Radiographic features
Hypodontia is usually assessed using orthopantomography, although cone beam CT may be utilized for problem solving.
Care should be taken not to confuse late calcification of the developing tooth bud with its absence and some authors suggest avoiding the diagnosis of hypodontia in children younger than 9 or 10 years old 3.
References
- 1. Al-Ani A, Antoun J, Thomson W, Merriman T, Farella M. Hypodontia: An Update on Its Etiology, Classification, and Clinical Management. BioMed Research International. 2017;2017:1-9. doi:10.1155/2017/9378325 - Pubmed
- 2. Valle AL, Lorenzoni FC, Martins LM et-al. A multidisciplinary approach for the management of hypodontia: case report. J Appl Oral Sci. 2012;19 (5): 544-8. Free text at pubmed - Pubmed citation
- 3. Rakhshan V. Congenitally Missing Teeth (Hypodontia): A Review of the Literature Concerning the Etiology, Prevalence, Risk Factors, Patterns and Treatment. Dent Res J. 2015;12(1):1. doi:10.4103/1735-3327.150286 - Pubmed
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