Dental agenesis is a condition in which some or all tooth buds are absent. It includes anodontia, hypodontia and oligodontia. Anodontia is a genetic disorder defined as the absence of all teeth.
It usually occurs as part of a syndrome that includes other anomalies. Also, rare but more common than anodontia are hypodontia and oligodontia. Hypodontia is genetic in origin and usually involves the absence of 1 to 5 teeth.
Oligodontia is genetic and is the term used to describe a condition where six or more teeth are missing.
Both temporary and permanent teeth can be affected by dental agenesis, but most cases involve the latter. This condition occurs after a specific pattern of missing teeth. Not only the number of missing teeth, but also the type of missing teeth should be considered.
Diagnosis
As all primary teeth are usually present by the age of three, their absence is usually noticed by parents who will consult a dentist.
With the exception of wisdom molars, all permanent teeth are usually present around the age of 12 to 14 years. When teeth have not erupted by this age, a panoramic dental X-ray should be taken to see if the tooth bud is at the level of the bone
Causes
When we have hypo/oligodontia or anodontia, they may also be associated with certain abnormalities of the hair, nails and sweat glands. In many cases, dental agenesis is a component of ectodermal dysplasia, a group of inherited disorders.
The causes of dental agenesis are not entirely known. Certain genes have been found to cause the condition, which can be either inherited or due to a genetic mutation in the egg or sperm.
This condition affects around 2-8% of the world’s population, and the frequency of missing teeth is as follows: maxillary lateral incisors, 2nd premolars, lower central incisors.
Treatment
The treatment of hypo/oligodontia or anodontia consists of dentures. Dentures that can aid chewing and improve the patient’s appearance.
In case of oligodontia or depending on the patient’s needs, treatment can be started early. Removable dentures could be proposed for children aged 3 to 4 years. These prostheses can be renewed as the child grows.
Another option in an adult patient who does not have a permanent 2nd premolar is orthodontic space closure, with the molars migrating mesial to fill the gap.
If only the front teeth are missing in hypodontia or oligodontia, a removable denture can be used to attach only the missing teeth. Permanent options for replacing missing teeth include dental implants, which is the best solution, but cannot be used in those under 18.
Apart from making chewing and speaking difficult, dental agenesis doesn’t cause many problems on its own.
However, if it is related to ectodermal dysplasia, problems with hair, nails, skin or sweat glands may also occur.
Whatever the cause, dental agenesis can be relatively easily managed with dentures, dental bridges or dental implants.
