hypodonti

Hypodontia is the developmental absence of one or more teeth, excluding the third molars. It may occur in isolation or as part of a broader syndrome. If six or more teeth are missing, the condition is usually called oligodontia; complete absence of all teeth is anodontia.

Prevalence estimates vary by population, but hypodontia affects a minority of people with permanent dentition. It is more common in the maxilla than the mandible and often involves the lateral incisors and second premolars, though any tooth can be affected. Hypodontia may be non-syndromic or associated with conditions such as ectodermal dysplasia or Down syndrome.

Causes are largely genetic, with mutations in genes such as PAX9, MSX1, and AXIN2 linked to tooth agenesis. Environmental factors and perinatal disturbances can contribute, but most cases are hereditary and familial patterns are observed. Hypodontia can occur as an isolated dental anomaly or as part of syndromes.

Diagnosis is typically made during childhood or adolescence through clinical examination and radiographs, including panoramic images, which reveal missing teeth and help distinguish hypodontia from delayed eruption. Early diagnosis supports planning.

Management is multidisciplinary and tailored to each patient. Orthodontic treatment can close spaces or align erupted teeth; space maintainers may preserve arch length when teeth are missing in child patients. For tooth replacement, options include implants (usually after growth completion), fixed bridges, or removable prostheses, sometimes with bone grafting.

Prognosis depends on the number and position of missing teeth and on access to multidisciplinary care. Regular follow-up and coordinated treatment planning enhance function, esthetics, and quality of life. Research continues to clarify its genetic basis and improve management strategies.