Abstract
Background: Dental treatment often requires prolonged mouth opening. This may compromise comfort during spontaneous nasal breathing and saliva swallowing, leading to stress or anxiety. A high-flow nasal cannula (HFNC) delivers warmed and humidified air at high flow rates and may improve breathing comfort; however, the feasibility of its routine use during dental treatment has not been established. Objectives: The primary objective of this pilot study is to evaluate the feasibility of conducting a definitive clinical trial to investigate the use of a HFNC during dental treatment. The secondary objective is to explore preliminary patient-centered outcomes related to stress and comfort to inform the design of future clinical trials. Methods: This single-center, open-label pilot feasibility study will be conducted at Nagasaki University Hospital, with adult patients undergoing routine full-mouth periodontal treatment participating in two treatment sessions, one without a HFNC and one with a HFNC, separated by at least four weeks. The primary feasibility outcomes include recruitment and retention rates, patient tolerance and acceptability of the HFNC, completeness of data collection, and device-related adverse events. The secondary outcomes are exploratory and include physiological stress-related parameters (pulse rate, respiratory rate, autonomic nervous system indices, and electroencephalographic alpha wave activity) and patient-reported comfort assessed using a questionnaire. Conclusions: This pilot study was designed to assess the feasibility and safety of HFNC use during full-mouth periodontal treatment and to inform the design of future definitive clinical trials. In particular, the resultant exploratory patient-centered outcomes and preliminary data may be used to guide outcome selection and sample size estimation.