Assessment of diurnal cortisol and oral health–related quality of life in surgically treated oral cancer patients rehabilitated with removable prostheses: pilot study

Surgical treatment of oral cavity cancer may result in anatomical defects and functional limitations affecting essential activities such as mastication, swallowing, and speech. The stress associated with cancer treatment and subsequent prosthetic rehabilitation may be reflected in salivary cortisol secretion and patients’ oral health-related quality of life (OHRQoL). However, the relationship between physiological stress markers and patient-reported outcomes during prosthetic rehabilitation remains insufficiently understood. This pilot study aimed to characterize diurnal salivary cortisol patterns in patients undergoing removable prosthetic rehabilitation following surgical treatment for oral cancer and to assess changes in OHRQoL over time, as well as the potential association between these outcomes. Nine edentulous patients who had undergone surgical treatment for oral squamous cell carcinoma and six healthy edentulous controls were included in the final analysis. All participants received removable acrylic complete dentures. Saliva samples were collected before prosthetic treatment and at 6 weeks, 3 months, 6 months, and 12 months after denture insertion. At each assessment, samples were collected at four time points (7:00 a.m., 12:00 p.m., 3:00 p.m., and 7:00 p.m.). Salivary cortisol concentrations were measured using a high-sensitivity enzyme immunoassay (Salimetrics LLC). OHRQoL was assessed using the OHIP-14 questionnaire. Diurnal variation in salivary cortisol concentrations was observed in both groups. No statistically significant between-group differences in total cortisol secretion, assessed using the area under the curve (AUC), or statistically significant longitudinal changes in cortisol levels were identified. At selected follow-up assessments, the oncological group showed numerically higher cortisol concentrations, particularly in the evening; however, these differences were not statistically significant. In the oncological group, mean OHIP-14 scores decreased from 35.1 at baseline to their lowest observed level of 27.3 at 6 months, indicating a descriptive improvement in OHRQoL. However, the available analyses did not establish a statistically significant improvement over time. No statistically significant association was detected between total cortisol secretion and OHIP-14 scores ( ρ = 0.125, p = 0.284). This pilot study identified descriptive differences in diurnal salivary cortisol patterns and changes in OHRQoL during prosthetic rehabilitation in patients treated surgically for oral cancer and healthy edentulous controls. Although OHIP-14 scores decreased during follow-up in the oncological group, the findings do not establish a statistically significant improvement attributable to prosthetic rehabilitation. Similarly, no statistically significant association between total cortisol secretion and OHRQoL was detected. The absence of a statistically significant association should not be interpreted as evidence that these outcomes are independent. Given the small sample size and substantial loss to follow-up, the findings should be considered preliminary and hypothesis-generating. Larger, adequately powered prospective studies are needed to clarify the relationships between prosthetic rehabilitation, salivary cortisol secretion, and OHRQoL.