# Impact of Visual and Auditory Relaxation Techniques on Autonomic Responses During Dental Procedures: A Randomized Controlled Trial

## TL;DR

This study tested how visual and auditory relaxation techniques affect stress during dental procedures, finding that some methods reduce stress while others increase it.

## Contribution

The study introduces new insights into the effects of specific visual and auditory relaxation techniques on autonomic responses during dental treatments.

## Key findings

- A hot eye mask with HSG sheet reduced heart rate and increased parasympathetic activity.
- Listening to nature sounds decreased respiratory rate and skin conductance.
- Noise-cancelling headphones increased respiratory rate and reduced HRV's high-frequency component.

## Abstract

Introduction: Relaxation methods for managing anxiety can help overcome and prevent dental treatment phobia. We investigated the effects of relaxation techniques targeting visual and auditory domains, which remain understudied, on dental treatment-related stress.

Methods: Thirty adult volunteers with dental anxiety were enrolled in a randomized, open-label, four-sequence, four-period crossover study evaluating the effects of the following interventions: wearing a hot eye mask with a heat- and steam-generating (HSG) sheet, wearing an inactivated HSG sheet, listening to nature sounds, and wearing noise-cancelling headphones. Interventions were separated by a washout period of at least two weeks to mitigate carry-over effects. Participants’ physiological parameters (autonomic nervous system function variables, skin conductance, and respiratory rate [RR] during dental treatment) were continuously monitored. The impact of these interventions on stress reduction was assessed.

Results: Application of a hot eye mask with an HSG sheet to the eye area reduced heart rate (HR) and increased the high-frequency component of HR variability (HRV) and skin conductance, indicating enhanced parasympathetic activity. Conversely, applying the inactivated HSG sheet tended to increase HR and low-frequency/high-frequency HRV ratios. Listening to nature sounds decreased RR and skin conductance and increased the high-frequency HRV component. Wearing noise-cancelling headphones increased the RR and decreased the high-frequency component of HRV.

Conclusions: Applying a hot eye mask with an HSG sheet and listening to nature sounds potentially reduced stress. However, applying an inactivated HSG sheet and using noise-cancelling headphones promoted sympathetic activity. Further research should subdivide anxiety scales and explore relaxation methods tailored to specific anxiety triggers.