Periodontal Diseases and Its Consequences in Head and Neck Cancer Patients Receiving Radiotherapy

Periodontal disease (PD) is a widespread oral complication that head and neck cancer (HNC) patients often experience. Available evidence suggests a strong link between PD and an increased risk of HNC because PD causes chronic low-grade inflammation, produces toxic and carcinogenic substances from the pathologic oral microbiome, and interferes with the tumor’s immune environment. Patients with HNC are typically treated with RT either as an adjunct to surgery or as a primary treatment, with or without chemotherapy. However, RT can cause various periodontal complications, as it damages the salivary glands (hyposalivation), cells in the oral cavity, vascular system, and the extracellular matrix and thus reduces the periodontium’s ability to heal and remodel. The patient’s susceptibility to plaque buildup may also play a crucial role in the progression of periodontal disease and attachment loss since radiation alters the dental biofilm. An irradiated periodontium, with its decreased repair ability, is more prone to infection and necrosis. Moreover, it may induce osteoradionecrosis, which is one of the most severe late complications of RT. Given the importance of periodontal care in the overall management of HNC patients undergoing RT, this chapter aims to provide an evidence-based analysis of the potential connection between periodontal disease and its consequences in this patient population.