Treatment for cancer during childhood often increases the risk for dental problems. It is important for children’s cancer survivors to understand why dental care is especially important.
Risk Factors for Dental Problems after Children’s Cancer Treatment
- Treatment with chemotherapy before permanent teeth were fully formed, especially if the patient was younger than 5 years old when treated.
- Radiation that included the head and mouth, such as:
- Cranial (whole brain)
- Craniospinal
- Nasopharyngeal (nose and throat)
- Oropharyngeal (mouth and throat)
- Orbital
- Eye
- Ear
- Infratemporal (midfacial area behind the cheekbones)
- Cervical (neck)
- Cervical spine (spine in the neck area)
- Mantle (neck and chest areas)
- Total body irradiation (TBI)
Dental Problems Resulting from Treatment
Problems that may result from chemotherapy during childhood include:
- Increased risk for cavities
- Shortening or thinning of the roots of the teeth
- Absence of teeth or roots
- Problems with development of tooth enamel resulting in white or discolored patches on the teeth, grooves and pits in the teeth, and/or easy staining of the teeth
Because teeth develop slowly, these problems are more likely to develop in people who received chemotherapy over a prolonged period (several years) during childhood.
Problems that may result from radiation to the mouth and/or salivary glands include:
- Increased risk for cavities
- Shortening or thinning of the roots of the teeth
- Absence of teeth or roots
- Faulty development of tooth enamel resulting in white or discolored patches on the teeth, grooves and pits in the teeth, and/or easy staining of the teeth
- Small teeth
- Early loss of teeth
- Baby teeth not falling out
- Problems with tooth development or delayed eruption of permanent teeth
- Increased risk of tooth sensitivity to hot and cold sensation
- Xerostomia (dry mouth due to decreased production of saliva)
- Alteration in taste
- Trismus (limited ability to fully open the mouth)
- Temporomandibular joint dysfunction (causing pain in front of the ears)
- Malocclusion (bite problem, such as overbite or under bite)
- Abnormal growth of bones of the face and neck
- Periodontal (gum) disease
Treating Dental Issues
Taking care of teeth and gums is always important, and it is even more important if a patient had radiation or chemotherapy at a young age. If an individual’s gums are not healthy, they can shrink away from teeth, causing infection in the bone supporting the roots. The bone can then dissolve away slowly, causing the teeth to become loose. This condition is called periodontitis, which means an inflammation surrounding a tooth. Periodontitis can be prevented by properly brushing the teeth and gums and by flossing between teeth at least once a day.
If a patient’s permanent teeth do not develop normally, they may need caps or crowns in order to improve the function of their teeth. Sometimes reconstructive surgery is needed to correct poor bone growth of the face or jaw.
Radiation can sometimes make it difficult to open a person’s mouth fully (trismus), or cause some scarring and hardening of the jaw muscles (fibrosis). Stretching exercises for the jaw may reduce fibrosis and improve the ability to open the mouth. A dentist will be able to instruct patients or refer them to occupational therapy to learn these exercises.
Crooked or small teeth may be improved by bonding. If braces are needed, a dentist will do a panorex X-ray of the teeth to see if the teeth, roots, and supporting bone are strong enough for braces.
Patients who had an allogenic bone marrow or stem cell transplant (from a donor other than themselves) should let their dentist know, so that the dentist can check for long-term complications indicating chronic graft-versus-host disease.
Xerostomia
Dry mouth, also called “xerostomia,” can occur after radiation to the head or neck. Other problems related to xerostomia include persistent sore throat, burning sensation in the mouth and gums, problems speaking, difficulty swallowing, hoarseness, or dry nasal passages. Dryness of the mouth is a result of decreased saliva and/or thickening of the saliva, and can lead to the development of cavities. This usually happens only with radiation doses of 40 Gy (4000 cGy/rads) or higher to the mouth and/or salivary glands. Drinking liquids frequently and the use of artificial saliva can help relieve the symptoms of xerostomia. Proper brushing habits are very important for people with xerostomia, as is limiting the intake of candy and other sweets. A dentist may also recommend applying a fluoride gel to teeth at least once a day to make the enamel more resistant to decay.
Precautions when Having Dental Work
Patients should always let their dentist know if they have the following health conditions:
- Shunt (surgical placement of a tube to drain fluid from the brain)
- Limb salvage procedure (replacement of bone with a metal rod or bone graft)
- Leaky heart valve (this sometimes happens after radiation to the chest)
In any of these situations, bacteria that normally enter the bloodstream during dental work can result in serious infections. As a precaution against infection, patients with the above conditions should take antibiotics before any dental work. The antibiotics should be prescribed by, or discussed with, the dentist. A dentist also needs to know if patients have had a splenectomy (surgical removal of the spleen) or if they have had high doses of radiation (30 Gy – 3000 cGy/rads or more) to the spleen.
What is the Risk of Developing Oral Cancer?
People who have had radiation to the head and neck during childhood may be at increased risk for oral cancers. Using tobacco in any form or using alcohol in combination with smoking greatly increases this risk. A dentist should perform an oral cancer screening exam during each visit. If a patient notices any of the following, they should notify their dentist immediately:
- A sore that does not heal or that bleeds easily
- A change in the color of mouth tissues
- A lump, thickening or rough spot in the mouth
- Pain, tenderness, or numbness anywhere in the mouth or on the lips.
Most of the time, these symptoms do not indicate any problem, but a dentist can tell if they are the sign of a serious problem.
Keeping Teeth and Mouths Healthy
Follow these recommendations (unless a dentist recommends otherwise):
- See a dentist regularly at least every six months. Make sure that the dentist has a complete health history with details of the treatment received. (Ask an oncologist for a summary of treatment.) A visit should include an oral cancer screening; patients need to notify their dentist if they notice any warning signs of oral cancer.
- Have a panorex X-ray done before dental/orthodontic procedures to evaluate the root development of teeth and determine if any modifications need to be made to the dental treatment plan.
- Brush teeth at least twice a day
- Use a toothpaste containing fluoride to help prevent tooth decay
- Place the brush at a slight angle toward the gum when brushing along the gum line
- Use a gentle touch, since vigorous brushing could irritate gums
- Clean all surfaces of the teeth
- Brush the tongue to remove bacteria that can cause bad breath
- Floss teeth once or twice a day. Floss carefully between teeth because brushing alone does not remove plaque between teeth. Use a gentle touch to avoid injury to gums. It is normal to have a small amount of bleeding when flossing. Notify the dentist if the bleeding increases or the gums are red and puffy as these may be signs of infection.
- Use antibacterial, alcohol-free fluoride mouth rinses.
- Drink liquids frequently and/or use artificial saliva.
- Apply fluoride frequently. The dentist may recommend a daily fluoride rinse or gel for use at home after brushing in addition to the special fluoride application received at regular dental cleanings.
- Limit sweets and carbohydrate-rich foods.
- Do not use tobacco products and use alcohol only in moderation.
- Notify the dentist immediately if any signs of infection develop in the mouth or gums, such as redness, tenderness, excessive bleeding of gums, painful teeth, and/or increased areas of sensitivity.