A rare genetic condition called cleidocranial dysplasia affects the development of the skull, collarbone, and teeth in particular. The condition can result in various physical features, including a large forehead, wide-set eyes, a small upper jaw, and dental problems. Cleidocranial dysplasia can also affect the growth and shape of the spine, hands, and feet, as well as the growth and shape of the spine. Although it doesn't impact intelligence or life expectancy, it can cause health complications.
It is caused by a mutation in a gene called RUNX2, which is responsible for bone and cartilage development. A child can inherit the mutation from one parent who has it or it can occur randomly in a child who has no family history of it. The inheritance pattern is called autosomal dominant, which means that a child has a 50% chance of inheriting the condition if one parent has it.
The symptoms of cleidocranial dysplasia vary from person to person, and some people may have mild or no symptoms at all. The most common symptoms include:
Delayed closure of the soft spots (fontanelles) and gaps (sutures) between the bones of the skull, which can result in a larger head circumference and a soft, bulging area on the top of the head.
Underdeveloped or missing collarbones (clavicles), which can allow the shoulders to be brought close together in front of the body.
Dental abnormalities, such as late eruption of permanent teeth, failure to lose baby teeth, extra teeth, crowded teeth, and misaligned teeth (malocclusion).
Short stature and delayed growth, which can affect the height and weight of the person.
Abnormal bone growth in the hands, feet, and spine, which can cause deformities, such as curved fingers, flat feet, and scoliosis (curvature of the spine).
Other possible symptoms include:
A high, narrow palate (roof of the mouth), which can affect speech and swallowing.
A prominent forehead, wide-set eyes, a flat nose, and a small upper jaw, which can affect the appearance of the face.
Hearing loss, ear infections, and sinus problems, which can result from abnormal development of the ear and nasal bones.
Breathing problems, such as sleep apnea, which can result from narrow airways and a small lower jaw.
Joint pain and arthritis, which can result from abnormal cartilage and bone development.
In order to diagnose cleidocranial dysplasia, a physical examination will reveal the characteristic signs of the condition, such as abnormalities in the skull, collarbone, and teeth. As a means of confirming the diagnosis and assessing the extent of bone and joint damage, X-rays, CT scans, or MRI scans can also be used. Identifying the mutation in the RUNX2 gene can help confirm the diagnosis and provide information for genetic counseling.
Cleidocranial dysplasia cannot be cured, but treatment can be used to manage its symptoms and prevent or treat complications. Orthopedists, dentists, orthodontists, otolaryngologists, and speech therapists may work together to treat the condition.
Surgery, which can be used to correct the bone and joint deformities, such as the skull, collarbone, spine, and hand problems. Surgery can also be used to remove extra teeth, improve the appearance of the face, and open the airways.
Dental care, which can include regular check-ups, cleaning, fluoride, and braces. Dental implants or dentures may be needed to replace missing or extracted teeth.
Hearing aids, which can help with hearing loss and improve communication.
Physical therapy, which can help with joint pain, mobility, and posture.
Medications, which can help with pain, inflammation, and infection.
Although cleidocranial dysplasia cannot be prevented, genetic counseling can be helpful to those with it or those at risk of passing it on to their children. In addition to providing information about inheritance patterns, chances of having a child with the condition, prenatal testing, and family planning, genetic counseling can also provide information about prenatal testing.
