imperfecta

Osteogenesis imperfecta (OI) is a genetic disorder in which bones fracture (break) easily. Sometimes the fractures happen for no known reason. OI can also cause weak muscles, brittle teeth, a curved spine, and hearing loss. OI is caused by one of several genes that aren't working properly. When these genes don't work, it affects how you make collagen, a protein that helps make bones strong.

OI can range from mild to severe, and symptoms vary from person to person. A person may have just a few or as many as several hundred fractures in a lifetime.

There is no specific test for OI. Your doctor uses your medical and family history, physical exam, and imaging and lab tests to diagnose it. Your doctor may also test your collagen (from skin) or genes (from blood). There is no cure, but you can manage symptoms. Treatments include exercise, pain medicine, physical therapy, wheelchairs, braces, and surgery.

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases

Your teeth are made of a hard, bonelike material. There are four parts:

• Enamel, your tooth's hard surface
• Dentin, the hard yellow part under the enamel
• Cementum, the hard tissue that covers the root and keeps your teeth in place
• Pulp, the soft connective tissue in the center of your tooth. It contains nerves and blood vessels.

You need your teeth for many activities that you may take for granted. These include eating, speaking and even smiling.

There are many different problems that can affect your teeth, including:

• Tooth decay - damage to a tooth's surface, which can lead to cavities
• Abscess - a pocket of pus, caused by a tooth infection
• Impacted tooth - a tooth did not erupt (break through the gum) when it should have. It is usually wisdom teeth that are impacted, but it can sometimes happen to other teeth.
• Misaligned teeth (malocclusion)
• Tooth injuries such as broken or chipped teeth

The causes of tooth disorders varies, depending on the problem. Sometimes the cause is not taking good care of your teeth. In other cases, you may have been born with the problem or the cause is an accident.

The symptoms can vary, depending on the problem. Some of the more common symptoms include:

• Abnormal color or shape of the tooth
• Tooth pain
• Worn-down teeth

Your dentist will ask about your symptoms, look at your teeth, and probe them with dental instruments. In some cases, you may need dental x-rays.

The treatment will depend on the problem. Some common treatments are:

• Fillings for cavities
• Root canals for cavities or infections that affect the pulp (inside of the tooth)
• Extractions (pulling teeth) for teeth that are impacted and causing problems or are too damaged to be fixed. You may also have a tooth or teeth pulled because of overcrowding in your mouth.

The main thing that you can do to prevent tooth disorders is to take good care of your teeth:

• Brush your teeth twice a day with a fluoride toothpaste
• Clean between your teeth every day with floss or another type of between-the-teeth cleaner
• Limit sugary snacks and drinks
• Don't smoke or chew tobacco
• See your dentist or oral health professional regularly

Your bones help you move, give you shape and support your body. They are living tissues that rebuild constantly throughout your life. During childhood and your teens, your body adds new bone faster than it removes old bone. After about age 20, you can lose bone faster than you make bone. To have strong bones when you are young, and to prevent bone loss when you are older, you need to get enough calcium, vitamin D, and exercise. You should also avoid smoking and drinking too much alcohol.

Bone diseases can make bones easy to break. Different kinds of bone problems include:

• Low bone density and osteoporosis, which make your bones weak and more likely to break
• Osteogenesis imperfecta makes your bones brittle
• Paget's disease of bone makes them weak
• Bones can also develop cancer and infections
• Other bone diseases, which are caused by poor nutrition, genetics, or problems with the rate of bone growth or rebuilding

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases

Your connective tissue supports many different parts of your body, such as your skin, eyes, and heart. It is like a "cellular glue" that gives your body parts their shape and helps keep them strong. It also helps some of your tissues do their work. It is made of many kinds of proteins. Cartilage and fat are types of connective tissue.

Over 200 disorders that impact connective tissue. There are different types:

• Genetic disorders, such as Ehlers-Danlos syndrome, Marfan syndrome, and osteogenesis imperfecta
• Autoimmune disorders, such as lupus and scleroderma
• Cancers, like some types of soft tissue sarcoma

Each disorder has its own symptoms and needs different treatment.

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases

Genes are the building blocks of heredity. They are passed from parent to child. They hold DNA, the instructions for making proteins. Proteins do most of the work in cells. They move molecules from one place to another, build structures, break down toxins, and do many other maintenance jobs.

Sometimes there is a mutation, a change in a gene or genes. The mutation changes the gene's instructions for making a protein, so the protein does not work properly or is missing entirely. This can cause a medical condition called a genetic disorder.

You can inherit a gene mutation from one or both parents. A mutation can also happen during your lifetime.

There are three types of genetic disorders:

• Single-gene disorders, where a mutation affects one gene. Sickle cell anemia is an example.
• Chromosomal disorders, where chromosomes (or parts of chromosomes) are missing or changed. Chromosomes are the structures that hold our genes. Down syndrome is a chromosomal disorder.
• Complex disorders, where there are mutations in two or more genes. Often your lifestyle and environment also play a role. Colon cancer is an example.

Genetic tests on blood and other tissue can identify genetic disorders.

NIH: National Library of Medicine