What is dentinogenesis imperfecta?

Experts like Dentist in Lahore describe the tooth disorder of dentinogenesis imperfecta as discoloration of the teeth (yellow-brown or gray-blue), loss of teeth, increased wear and tear, and weaker than normal teeth. This hereditary disorder can appear in permanent or primary (baby) teeth. Read on to know more about dentinogenesis imperfecta:

What is dentinogenesis imperfecta?

Dentinogenesis imperfecta causes formation of weaker than normal teeth, which are mostly discolored, and prone to breakage. This brittleness is the result of rare genetic disorder affecting the dentin of the teeth. Dentin is the second layer of the tooth, just beneath the enamel. 

In case of abnormal formation of dentin, the middle layer of the tooth is abnormally soft, making the tooth prone to tooth fractures and pitting of the enamel. In individuals suffering from dentinogenesis imperfecta, there are often speech problems as well. 

The hereditary pattern of dentinogenesis imperfecta is autosomal dominant. This means that a single copy of disease producing genes—DSPP—inherited from one parent is enough to cause disease. Genes are inherited as pairs, one from each parent. In autosomal dominant diseases, even one gene is enough to cause disease. In most cases, the parent also has a dominant copy and suffers from the same disease. However, it is also possible for the genes to have spontaneous mutation and change de novo without any evidence of the disease in the parents. 

What are the types of dentinogenesis imperfecta?

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

• Type I: this type of dentinogenesis imperfecta occurs in individuals who also suffer from osteogenesis imperfecta—the genetic condition with mutation in collagen formation, resulting in weak bones prone to fractures.
• Type II: this is the commonest type of dentinogenesis imperfecta. Usually, there is no concurrent hereditary disorder with this type, however, many people with this type of dentinogenesis imperfecta have hearing loss in older age. This hearing loss is progressive and related to high-frequency sounds. 
• Type III: this type of disease occurs alone, without any other concurrent hereditary disorder. This type was first seen in families living in southern Maryland, and also in people of Ashkenazi Jewish origin. 

What are the symptoms of dentinogenesis imperfecta?

The symptoms of dentinogenesis imperfecta are:

• Fragile teeth 
• Grayish appearance of teeth
• Hypoplasia of dental enamel
• Hypocalcification of the dental enamel 

What are the causes of dentinogenesis imperfecta?

Researchers have found that mutations in DSPP gene are linked to this disorder—type II and III. In type I dentinogenesis imperfecta, several other genes are involved, most often COL1A1 or COL1A2 as this is a part of osteogenesis imperfecta. 

DSPP genes are responsible for making the protein called dentin, which is defective in dentinogenesis imperfecta. Consequently, the middle layer of the tooth is weak, making the teeth prone to discoloration, decay, breakage and weakness. 

How is dentinogenesis imperfecta diagnosed?

The diagnosis of dentinogenesis imperfecta is made through clinical exam, which differs according to the type of dentinogenesis imperfecta:

• Type I: people with this type of dentinogenesis imperfecta also have osteogenesis imperfecta and thus other health concerns as well. Typically, the changes of this disease are not seen on dental X-ray. 

• Type II: the diagnosis of this type is reliant on clinical examination by the dental care provider. The teeth show signs of discoloration, short roots, missing pulp chambers—the innermost layer—and opalescent dentin. 

• Type III: with this type of disease, the patient shows signs of opalescent primary and permanent teeth. Similar to type II, there are also large pulp chambers in type III. 

How is dentinogenesis imperfecta treated?

The treatment varies according to disease severity, age of the patient and the concerning symptoms. The main goal of therapy is to deal with pain and infection, while restoring the aesthetics and protecting the teeth from wear. Experts at Fatima Memorial Hospital treat dentinogenesis imperfecta through amalgams, dental fillings, crowns, caps and veneers to fix the discoloration of teeth.