Dentinogenesis imperfecta is a condition characterized by teeth that are translucent and discolored (most often blue-grey or yellow-brownin color). Individuals with this disorder tend to have teeth that are weaker than normal, which leads to wear, breakage, and loss of teeth. This damage can include teeth fractures or small holes (pitting) in the enamel. Dentinogenesis imperfecta can affect both primary (baby) teeth and permanent teeth. People with this condition may also have speech problems or teeth that are not placed correctly in the mouth. Dentinogenesis imperfecta is caused by mutationsin the DSPP gene and is inherited inan autosomal dominant manner.

According to the original classification, there are three types of dentinogenesis imperfecta:

• Type I: occurs in people who have osteogenesis imperfecta, a genetic condition in which bones are brittle, causing them tobreak easily. People with this type of dentinogenesis imperfecta have mutationsin COL1A1orCOL1A2.
• Type II: usually occurs in people without another inherited disorder. Some families with type II also have progressive hearing loss inolder age. Type II is the most common type of dentinogenesis imperfecta.
• Type III: usually occurs in people without another inherited disorder. Type III was first identified in a group of families in southern Maryland and has also been seen in individuals of Ashkenazi Jewish descent.

Some researchers believe that dentinogenesis imperfecta type II and type III, along with a similar condition called dentin dysplasia type II, are actually just different forms of a single disorder.

Dentinogenesis imperfecta is inherited in an autosomal dominant manner, which means only one changed copy of DSPP in each cell is sufficient to cause the disorder. We inherit one copy of each gene from our mother and another copy from our father. In most cases, a person who is affected with dentinogenesis imperfecta has one parent with the condition, although it is possible for the condition to occur for the first time in an individual who does not have affected parent. In these cases, the change in the gene is known as de novo because it was not inherited from either parent.

Dentinogenesis imperfecta is diagnosed by a clinical exam that is consistent with signs of the condition. A dental X-ray is specifically helpful in diagnosing dentinogenesis imperfecta. The specific signs found in a clinical exam may differ depending on the type of dentinogenesis imperfecta:

• Type I: people who have type I dentinogenesis imperfecta also have osteogenesis imperfecta. This will cause them to have other health concerns, so they will typically not be diagnosed by dental X-ray.
• Type II: people who have type II dentinogenesis imperfecta will be expected to show signs such as amber or multicolored (opalescent) dentin, short roots, and missing pulp chambers of the teeth. The pulp chamber is the innermost layer of the tooth.
• Type III: people who have type III dentinogenesis imperfecta will be expected to show signs such as multicolored (opalescent) primary and permanent teeth and large pulp chambers.

The aims of treatment for dentinogenesis imperfecta are to remove sources of infection or pain, restore aesthetics, and protect teeth from wear. Treatment varies according to the age of the patient, severity of the problem, and presenting complaint. Treatment options include amalgams as dental fillings, veneers to fix the discoloration of teeth, crowns, caps, and bridges.

Dentures or dental implants may be necessary if the majority of teeth are lost. Some dentists may also recommend resin restorations and teeth bleaching.