This case report focuses on the rising incidence of oral and maxillofacial tumors, requiring multimodal therapy involving surgery and radiotherapy. Radiotherapy, integral to cancer treatment, poses oral health challenges, notably radiation-related caries. Severe complications such as mucositis, xerostomia, and osteoradionecrosis highlight the critical role of optimal oral hygiene practices in managing these conditions. The presented case involves a 38-year-old male with a history of verrucous carcinoma, undergoing composite resection, modified neck dissection, and pectoralis major myocutaneous flap reconstruction. Adjuvant radiotherapy requires a comprehensive approach to minimize complications. Here, the focus is on fluoride treatment, specifically Fluoritop SR Dental Varnish, to prevent radiation-related caries. A multidisciplinary approach, including fluoride application, vigilant monitoring, patient education, and collaboration, is crucial for minimizing complications in oral malignancy radiotherapy. Emphasizing fluoride’s significance in preventing radiation-related caries, this care plan contributes to awareness and improves oral health outcomes in this patient population.