In addition to the desired antitumor effects, head and neck radiation therapy induces damage in normal tissues that may result in oral sequelae such as mucositis, hypo‐salivation, radiation caries, taste loss, trismus, soft‐tissue necrosis, and osteoradionecrosis. These sequelae may be dose‐limiting and have a tremendous effect on the patient's quality of life, Current policies to prevent these sequelae primarily are based on clinical experience and show great diversity. A protocol for the prevention and treatment of oral sequelae resulting from head and neck radiation therapy, based on fundamental research and data derived from the literature, is presented. The protocol is particularly applicable in centers with a dental team. This team should be involved at the time of initial diagnosis so that a successful preventive regimen is an integral part of the overall cancer treatment regimen.

In this study the effect of X-ray irradiation on demineralization of bovine dental enamel in vitro was investigated. Enamel specimens were irradiated with 72 Gy and subsequently demineralized (140 h) under reproducible constant composition conditions at pH = 5 in the presence of methylhydroxydiphosphonate (MHDP). Microhardness measurements after demineralization without MHDP showed significant differences (p < 0.001) between irradiated and nonirradiated enamel specimens; no significant differences were found in the presence of MHDP. Quantitative microradiography showed that both mineral loss and lesion depth were significantly lower (p < 0.001) for the irradiated enamel specimens compared with the nonirradiated ones. Surface layer formation was observed in irradiated enamel demineralized in a solution without MHDP. It was shown that X-ray irradiation decreased the enamel acid solubility in vitro.

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Apparent viscosities at different shear rates were measured for 3 types of saliva substitutes: (a) mucin‐containing saliva; (b) substitutes based upon carboxymethylcellulose (CMC), and (c) solution of polyethylenoxide (PEO). The apparent viscosities were compared with those of human whole saliva. Human whole saliva and mucin‐containing saliva substitutes appeared to be similar in their rheological properties. Both types of solution are viscoelastic solutions and adjust their apparent viscosities to their biological functions. Preparations containing CMC or PEO are non‐Newtonian liquids. From this study it is concluded that mucin‐containing saliva substitutes appear to be the best substitutes for natural saliva, as far as rheological properties are concerned.