The effect of head and neck radiation therapy on salivary biochemical indicators

Saliva plays a crucial role in preserving and maintaining oral health. Hyposalivation due to head and neck radiation therapy may induce changes to the biochemical properties of the saliva. The aim of this study was to analyze and compare saliva properties before and after radiation therapy in patients with head and neck cancers. In this quasi experimental study, 18 patients (13 male, 5 female) with head and neck cancers were evaluated regarding the flow rate of saliva, buffering capacity, amylase, total protein, IgM, IgA, IgG and albumin concentration of saliva prior to and following radiotherapy by schirmer test, pH meter, biuret, turbidometry and spectrophotometry. The oral symptoms due to radiotherapy (xerostomia, loss of taste, difficulty in swallowing, eating and speaking) were evaluated according to the patient's complaints. S tatistical analysis of the results was performed with paired t test. There was statistically significant changes in flow rate (28.27±7.8 Vs 10.94±12.2), salivary buffering capacity (6.47±0.68 Vs 5.06±0.52), amylase (2536.5±707.9 Vs 1053.23±343.5) and IgM concentration (0.87±1.8 Vs 0.04 ±0.07) before and after radiation therapy (p≤0.05). There were no significant changes in total protein, albumin, IgA and IgG concentration after radiotherapy. Clinical manifestations of xerostomia, loss of taste, difficulty in swallowing and eating, and difficult speaking were detected in 100%, 100%, 83.3% and 16.7% of the cases, respectively. Based on the results of this study, head and neck radiation therapy leads to reduction in salivary flow rate, buffering capacity, amylase and IgM concentration.