Four Oral Side Effects Of Radiation Therapy

2 October 2015
 Categories: Dentist, Articles

Radiation therapy is a commonly used treatment for cancers of the oral cavity, but it can have a lot of side effects inside your child's mouth. This is because radiation doesn't just affect the cancer cells, it also affects the healthy cells. Here are four oral side effects that your child may encounter as a result of their treatment.


Trismus, also called lockjaw, is a possible complication of radiation treatment. This can happen because radiation causes changes in your healthy cells. When your healthy cells are exposed to radiation, they produce more fibrin, a type of protein, than they otherwise would, and this excess fibrin builds up in the radiated tissue. Fibrin is what makes scar tissue, so the affected tissues will become tough and stiff like scars. The resulting stiffness can make it harder for you to open your mouth, resulting in trismus.

Trismus is a serious concern, because it makes it hard to eat, talk, or even brush your teeth. Fortunately, your child's dentist can help you manage the condition. The main treatment for this condition is jaw stretching; your dentist can help your child stretch their jaw and also may recommend a jaw stretching device to use at home.


Osteoradionecrosis, the medical term for death of the jawbone, is a very severe side effect of radiation treatment. Radiation damages some of the blood vessels that supply your jawbone with blood, and without enough blood, your jawbone is unable to heal itself as well as it used to. This means that you're not able to heal from trauma as well, and you may be more susceptible to infections. If your child gets a tooth pulled out or injures their jaw in an accident after they have undergone radiation therapy, they may then develop osteoradionecrosis.

If your child develops this complication, the main treatment is hyperbaric oxygen therapy. During this treatment, your child will sit in a room or chamber increased air pressure, and this will allow their lungs to take in more oxygen. The increased oxygen will help their bones heal.


The lining of your mouth is called the oral mucosa, and it is very sensitive to radiation. When your mouth is exposed to radiation, your oral mucosa may become sore and swollen, and you may develop painful open sores on your oral tissues. These symptoms will make it painful for you to chew or swallow. The symptoms of mucositis can start as soon as two or three weeks into your child's radiation treatment.

Mucositis tends to go away two or three weeks after the treatment finishes, but since it is so uncomfortable, your dentist can offer treatments to help your child manage the symptoms while you wait for them to go away. Your dentist may prescribe an anesthetic mouth rinse for your child to use before they eat and may recommend choosing bland, soft foods that are less likely to irritate their mouth.

Gingival Bleeding

Radiation therapy can destroy your platelets, a type of blood cell that is responsible for making your blood clot. Without enough platelets, you will bleed more easily and the bleeding will be more difficult to get under control. This low platelet level, known as thrombocytopenia, can make your gums bleed more easily. Your child may find it difficult or impossible to brush or floss their teeth without causing excessive bleeding.

This bleeding is a big concern, because it makes it hard for your child to clean their teeth. Fortunately, your dentist can help your child keep their teeth clean. They may be told to use a sponge instead of a toothbrush, and if even that causes bleeding, they may be told to rinse their mouth with a baking soda solution. Your dentist may tell your child to stop flossing completely until the bleeding is under control.

If you think your child is suffering from any of these side effects, make sure to tell a pediatric dentist, like those found at, immediately.