Radiation therapy is a common treatment mode used for a variety of cancers. External beam therapy is used most in the United States, where in Europe and other countries brachytherapy, or the intralesional placement of radioactive sources, is also used.
Depending on the site, stage of tumor, and type of radiation used, a regimen is established indicating the frequency, duration, and amount of radiation to be provided to the patient. For example, a patient with neck node involvement may receive a daily fraction of 2 Gray (Gy) five days per week for 7 weeks, for a total of 70 Gy.
Common complications of head and neck radiation therapy include mucositis (mouth sores), dry mouth, dysgeusia (loss of taste), trismus (difficulty opening widely), and osteoradionecrosis.
Radiation oncologists have developed sophisticated strategies aimed at maximizing doses to cancerous tissue and minimizing doses to non-diseased tissue. This may be done using blocks and shields. Intensity Modulated Radiation Therapy (IMRT) uses computer design to minimize complications; for example, a parotid sparing protocol is meant to maintain saliva flow when possible.
Combination modalities may add forms of chemotherapy while radiation therapy is being administered to maximize efficacy and minimize side effects.
For more information about radiation therapy and oral health, see these resources:
Dental Management of the Head and Neck Cancer Patient Treated with Radiation Therapy: Update 2021 - Michigan Dental Association
Oral Care During Head and Neck Radiotherapy - Special Care Dentistry Association
Oral Care After Head and Neck Radiotherapy - Special Care Dentistry Association
Head and Neck Cancer Survivorship Care Guideline - American Society of Clinical Oncology Clinical Practice Guideline Endorsement of the American Cancer Society Guideline
Head and Neck Radiation Treatment and Your Mouth - National Institutes for Health
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