The likelihood is high that aggressive cancer treatment will have toxic effects on normal cells as well as cancer cells. The gastrointestinal tract, including the mouth, is particularly prone to damage. This is true whether the treatment is radiation or chemotherapy. Most patients being treated for head and neck cancer will experience some oral complications, and while most of these are manageable, complications can sometimes become severe enough that treatment must be completely stopped. In addition, surgical solutions to tumor removal may lead to oral and nutritional problems as well.

The most common oral problems occurring after radiation and chemotherapy are mucositis (an inflammation of the mucous membranes in the mouth), infection, pain, and bleeding. Other possible complications might include dehydration and malnutrition, commonly brought on by difficulties in swallowing (dysphagia). Radiation therapy to the head and neck may injure the glands that produce saliva (xerostomia), or damage the muscles and joints of the jaw and neck (trismus). These treatments may also cause hypovascularization (reduction in blood vessels and blood supply) of the bones of the maxilla or mandible (the bones of the mouth). In addition, treatments may affect other forms of dental disease (caries, or soft tissue complications), or even cause bone death (osteonecrosis).

By identifying patients at risk for oral complications, health care providers are able to start preventive measures before cancer therapy begins, reducing the occurrence of problems brought about by different treatment modalities. The most important risk factors leading to problems are oral or dental disease that already exists, and poor oral care during cancer therapy. Other risk factors include the type of cancer, the chemothe