Essential Dental Care Before Head & Neck Radiation

Radiation to the head and neck permanently reduces the blood supply to the jaw. Bone that once healed well after a tooth was pulled may not heal at all afterward. That one fact drives the whole sequence. Dental problems get fixed before radiation starts, while the jaw can still repair itself. The National Cancer Institute suggests an oral health check at least a month before cancer treatment begins. That usually leaves enough time for the mouth to heal if you need dental work.

This is not a cosmetic review. The dentist looks for advanced decay that could reach the nerve of the tooth. They look for moderate or severe gum disease. They look for infection at the root tip that has caused symptoms in the past 90 days. They also check for impacted or partly erupted teeth, and for dentures or appliances that rub the lining of the mouth. Anything that could turn into an infection later gets flagged now.

Ask your radiation oncologist to send your planned treatment fields and doses to the dentist. The risk sits in bone that will get a high dose. Published extraction guidelines from the University of Florida College of Dentistry point to teeth in fields above roughly 5,000 cGy as the ones that need decisions. Below that level, the guidelines note, the risk of bone breakdown is minimal.

Extraction sites need time to close before the beam starts. Those same guidelines call for a minimum of 14 to 21 days of healing before radiation begins. Two to three weeks is the common advice. This is where scheduling pressure shows up, because everyone wants treatment to start quickly. If the calendar looks tight, say so in clinic. Ask the radiation oncologist, the surgeon and the dentist to agree on the order together. Otherwise each may assume another has handled it.

Osteoradionecrosis is bone in the jaw that dies and fails to heal after radiation. In treated areas the risk is there for the rest of your life. There is no waiting period after which extractions become routine again. Years later, a general dentist who does not know your history may plan an extraction the way they would for anyone else. Keep the treatment dates, the site treated and the dose somewhere you can find them. Say "I have had radiation to my head and neck" before any dental procedure, including implants.

Salivary glands can start to fail within about a week of the first session. Often they never fully recover. Less saliva means decay can move fast, even in people who never had cavities. Custom fluoride trays are usually made before treatment begins. NCI describes putting on fluoride gel once a day at bedtime, after cleaning the teeth. For a sore mouth, the standard advice is a rinse of a quarter teaspoon of salt and a quarter teaspoon of baking soda in one quart of water, used every two hours. Mouth soreness from radiation commonly lasts six to eight weeks.

Trismus means trouble opening the jaw. The risk rises with higher radiation dose and with repeated courses. Teams usually start jaw-opening exercises early rather than waiting for stiffness to set in. Range of motion is easier to keep than to regain. Ask when to begin and how many times a day.

• Call 911 or go to an emergency department if a dental infection makes it hard to breathe, speak or swallow, if swelling spreads across your mouth, cheek or under your jaw, if an eye becomes swollen or painful or your vision changes, or if your mouth will barely open. The NHS treats these as 999 signs, because infection around the jaw can push on the airway (NHS).
• Call your dental or oncology team the same day if a tooth turns painful or loose, the gum swells, or you notice pus, a bad taste or a bad odor. Bare bone showing through the gum, a sore that will not heal, or a fever also belong in the same-day group. So does a jaw that suddenly opens less than it did.
• Call your care team within a day or two if you cannot eat or drink enough, mouth pain is not controlled by what you have been given, or you are skipping brushing because it hurts.

Persistent gaps in daily cleaning are the most common route to preventable damage in a dry mouth.

• University of Florida College of Dentistry - Guidelines for Dental Extractions Before Head & Neck Radiation Therapy
• American Dental Association - Cancer Therapies and Dental Considerations
• NCI - Oral Complications of Cancer Therapies (health professional version)
• NHS - Dental abscess