What are the other Names for this Condition? (Also known as/Synonyms)

• Dental Ankylosis
• Molar I Reinclusion
• Secondary Retention of Permanent Molars

What is Ankylosis of Teeth? (Definition/Background Information)

• Ankylosis of Teeth is a rare disorder characterized by the fusion of the tooth to the bone, preventing both eruption and orthodontic movement
• The periodontal ligament is obliterated by a 'bony bridge' and the tooth root is fused to the alveolar bone
• Ankylosis of Teeth can affect both primary and permanent teeth, may occur at any time during eruption and can lead to submergence. Permanent molars are less frequently affected than deciduous molars. Varying numbers of teeth may be affected
• After eruption, it halts any adaptive changes. In a growing child, an ankylosed tooth appears to 'submerge' as adjacent unaffected teeth and alveolar bone continue their normal pattern of growth occlusally
• The disorder may result in loss of the retained molar and neighboring teeth due to caries and periodontal disease, and in deformation of the facial skeleton (reduction in the height of the lower face, relative mandibular prognathism, posterior open bite)
• The major characteristic of a secondarily retained molar is infraocclusion that may result in malocclusion. Occasionally, Ankylosis of Teeth may be associated with fifth finger clinodactyly.

(Source: Dental ankylosis; Orphanet, National Institute of Health and Medical Research (INSERM), Paris.)

Who gets Ankylosis of Teeth? (Age and Sex Distribution)

• Ankylosis of Teeth is a rare congenital disorder of unknown prevalence. The presentation of symptoms may occur at birth
• Both males and females may be affected
• Worldwide, individuals of all racial and ethnic groups may be affected

What are the Risk Factors for Ankylosis of Teeth? (Predisposing Factors)

• A positive family history may be an important risk factor, since Ankylosis of Teeth can be inherited
• Other factors that may contribute to the condition include injury, infection, and inflammation

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Ankylosis of Teeth? (Etiology)

• Etiology remains uncertain but a genetic predisposition to Ankylosis of Teeth with autosomal dominant inheritance has been suggested
• Familial occurrence has been shown in several families
• Trauma, inflammation or infection may play a causative role

(Source: Dental ankylosis; Orphanet, National Institute of Health and Medical Research (INSERM), Paris.)

Autosomal dominant: Autosomal dominant conditions are traits or disorders that are present when only one copy of the mutation is inherited on a non-sex chromosome. In these types of conditions, the individual has one normal copy and one mutant copy of the gene. The abnormal gene dominates, masking the effects of the correctly function gene. If an individual has an autosomal dominant condition, the chance of passing the abnormal gene on to their offspring is 50%. Children, who do not inherit the abnormal gene, will not develop the condition or pass it on to their offspring.

What are the Signs and Symptoms of Ankylosis of Teeth?

Based on the frequency of signs and symptoms of Ankylosis of Teeth observed, the following information may be noted:

• Very frequently present symptoms in 80-99% of the cases: Reduced number of teeth
• Frequently present symptoms in 30-79% of the cases: Abnormality of dental enamel
• Occasionally present symptoms in 5-29% of the cases: Clinodactyly of the 5th finger
• Other signs and symptoms include: Abnormality of the dentition

(Source: Dental ankylosis; Orphanet, National Institute of Health and Medical Research (INSERM), Paris.)

How is Ankylosis of Teeth Diagnosed?

• Clinical examination and X-ray are the main diagnostic methods for detecting Ankylosis of Teeth

(Source: Dental ankylosis; Orphanet, National Institute of Health and Medical Research (INSERM), Paris.)

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Ankylosis of Teeth?

The complications of Ankylosis of Teeth may include:

• Deformity of the mouth
• Cosmetic concerns

Complications may occur with or without treatment, and in some cases, due to treatment also.

How is Ankylosis of Teeth Treated?

The recommended management includes the following:

• Removing the ankylosed tooth to ensure development and eruption of the permanent teeth
• Surgery to expose, protect, or reposition the emerging tooth

(Source: Dental ankylosis; Orphanet, National Institute of Health and Medical Research (INSERM), Paris.)

How can Ankylosis of Teeth be Prevented?

• Ankylosis of Teeth may not be preventable, if the condition runs in one’s family 
• Genetic testing of the expecting parents (and related family members) and prenatal diagnosis (molecular testing of the fetus during pregnancy) may help in understanding the risks better during pregnancy
• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders
• Regular medical screening at periodic intervals with tests and physical examinations are recommended

What is the Prognosis of Ankylosis of Teeth? (Outcomes/Resolutions)

• The prognosis of Ankylosis of Teeth is dependent upon the severity of the signs and symptoms and associated complications, if any
• Individuals with mild conditions have better prognosis than those with severe symptoms and complications
• Typically, the prognosis may be assessed on a case-by-case basis

Additional and Relevant Useful Information for Ankylosis of Teeth:

• Ankylosis of Teeth is also known by the following names: Abnormal Fusion of Dental Cementum with Alveolar Bone

The following DoveMed website link is a useful resource for additional information:

http://www.dovemed.com/diseases-conditions/rare-disorders/