RADIOTHERAPY AND ITS DENTAL IMPLICATIONS

Introduction
You may be worried about the side effects from your radiation treatments. As both the mouth and neck areas will be exposed to radiation, you will experience some side effects involving your teeth, mouth and appetite. Most of the side effects start within 2-3 weeks of treatment but can increase throughout the duration of the radiation. Some side effects are temporary and will improve with time; however, others may be permanent.

Dental Examination
Radiation therapy of the head and neck cancers can increase your risk of getting dental caries. Oral care designed to prevent problems will be a very important part of your treatment. Before starting radiation therapy, your radiation oncologist will refer you for a dental examnination. Dental X-rays will be taken and a comprehensive examination to check for caries, periodontal disease, abscessed teeth, retained root tips and any other conditions that may cause problems during or after radiation therapy will be carried out. You will undergo the necessary dental treatments before the commencement of your radiation therapy.

Skin redness and irritation
The skin are undergoing radiation may become red and itchy. Be very careful not to apply anything unless instructed by yout radiation oncologist. Depending on the area treated and dosage used, your skin may or may not return to normal.

Sores in the mouth (Mucositis)
Soreness in your mouth will usually appear in the second and third week of the radiation therapy. It is likely to decrease from the fifth week onwards up to a month after your treatment ends. The sores and ulcers are usually uncomfortable and may interfere with normal chewing, speech and oral hygiene.

Avoid spicy foods that will irritate your mouth. Mouth rinses that are alcohol-based should be avoided as they worsen the condition. The use of warm alkaline saltwater (one tablespoon of salt and one teaspoon of baking soda dissolved in 8oz of warm water) will lubricate the tissue and improve your comfort. You can use this as often as you wish. If the sores are severe, an anesthetic gel may be used to numb the mouth before eating or brushing. If you experience difficulties with these activities, your physician or dentist can prescribe the appropriate medication for you.

Changes in taste (Dysgeusia)
Food will taste differently during your radiation therapy. The taste buds are affected by the radiation. Usually the sense of taste will improve over time, in most people the taste sensations return to normal within six months to a year.

Dry mouth (Xerostomia)
Radiation affects the salivary glands resulting in a decrease in the normal salivary flow. After a couple of weeks, the saliva that is present will thicken and make swallowing difficult. You should drink as much fluid as possible as this will loosen the thick saliva and lubricate the mouth.

When eating, you should try to take a drink between each bite of food. Pureed food will be easier to eat and the use of sauces, gravy and butter will be beneficial in moistening the food. Eating more often with smaller portions will be easier than eating traditional three meals daily. If you have difficulty eating, ask your physician for liquid food supplements. When the dryness worsens, you may use salivary substitutes, which are available at the pharmacy.

Tooth decay (Caries)
Saliva serves to lubricate and protect the tooth. When salivary flow is decreased, the protective mechanism of the saliva is diminished and thus the teeth will be very susceptible to dental caries.

It is very important that you brush regularly after each meal to prevent decay. You must avoid foods that are high in sugar content. Your dentist can fabricate a customized tray to help apply fluoride to your teeth. The use of fluoride will help to prevent caries. It is important to see your dentists regularly every 3 to 6 months to check on your dental status.

Bone death (Osteoradionecrosis)
The most sever side effect of radiation is osteoradionecrosis. Radiaiton destroys some of the small vessels, which provide nutrients and oxygen to the living bone. A reduction in these vessels correlates to a reduction is the bone's ability to heal itself. Should you require tooth extraction after radiation therapy, you are at risk of developing osteoradionecrosis. This is a difficult condition to treat; therefore, a strict preventive programme is important.

Limited mouth opening (Trismus)
Trismus is another complication that may develop after radiation therapy. Trismus occurs as a result of scarring (fibrotic changes) of the muscles of chewing, when they are included in the radiation field. Limited mouth opening, combines with dry mouth, may interfere with the ability to maintain oral hygiene, speech and eating. Stretching exercises are important to minimize post treatment trismus. Use of wooden tongue spatulas taped together or corkscrew appliances and exercising 10 to 15 times per day for 10-minute sets can be effective to decrease the severity of trismus.

Use of prosthesis (Dentures)
Due to the decrease in saliva and the soreness in the mouth, you should avoid wearing your dentures during the treatment. Following the completion of your radiation therapy you should consult with your dentist before you begin to wear dentures again. If you find major differences in fit, consult your dentist to correct the fit of your dentures.