Radiation therapy to treat cancer may cause a dry mouth from damage to salivary glands which may increase the risk of cavities on the teeth. The consistent use of prescription fluoride on teeth after radiation therapy for head and neck cancer may reduce the development of cavities and tooth loss. The purpose of this study is to find out if prescription fluoride varnish applied to the teeth every three months during the first year after radiation therapy changes the development of cavities or gum problems.

The overall objective of this clinical trial is to determine if oncology practices can reduce dental disease in head and neck cancer patients post radiation therapy. Participants will have fluoride varnish applied at planned oncology follow-up visits and medical oncology providers will be instructed on recognizing dental disease and referring head and neck cancer patients for dental care when needed.

Inclusion Criteria:

• Aged 18 years and older
• Willing and able to provide signed and dated consent form
• Presence of at least 4 natural erupted teeth remaining in the mouth after completion of pre-RT dental management
• Diagnosed with head and neck squamous cell carcinoma (SCC) or a salivary gland cancer (SGC), and intends to receive external beam radiation therapy (RT) with curative intent (tumor eradication), with or without concomitant chemotherapy;

OR

• Diagnosed with a non-SCC, non-SGC malignancy of the head and neck region, and intends to receive RT, with or without concomitant chemotherapy. The participant must be expected to receive at least 4500 cGy to one of the following sites:

  1. base of tongue
  2. buccal/labial mucosa
  3. epiglottis
  4. floor of mouth
  5. gingiva/alveolar ridge
  6. hard palate
  7. hypopharynx
  8. larynx
  9. lip
  10. mandible
  11. maxilla
  12. maxillary sinus
  13. nasal cavity
  14. nasopharynx
  15. neck
  16. oral cavity
  17. oral tongue
  18. oropharynx
  19. paranasal sinus/orbit
  20. parotid gland
  21. pharynx
  22. retromolar trigone
  23. soft palate
  24. sublingual gland
  25. submandibular gland
  26. tonsil;

• Willing to comply with all study procedures

• Willing to participate for the duration of the study

• RT follow-up planned for one of the selected AH Oncology Specialist Follow-up Sites.

Exclusion Criteria:

• Receiving palliative RT
• History of prior curative RT to the head and neck region to eradicate a malignancy.
• Incarcerated at the time of screening
• Anything that would place the participant at increased risk or preclude the participant's full compliance with or completion of the study.

As this is a pilot study which forms the basis of a larger clinical trial, individual deidentified participant data will be shared upon reasonable request to the primary investigators, along with a data dictionary outlining variables collected and data collection forms when appropriate.

IPD will be available December 1, 2025 until at least December 1, 2030.

Individual deidentified participant data as outlined above will be shared upon reasonable request to the primary investigators until the conclusion of the follow-up study (approximately December 2030)