General Medicine · Medical Literature
Electrodermal activity during dental procedures: effects of procedure type, age, and audiovisual interventions.
Abstract
Dental anxiety affects roughly 15% of the general population, yet the relative contribution of procedure type, patient age, and distraction interventions to objective autonomic arousal during dental treatment remains poorly characterised. This study investigated the effects of these three factors on electrodermal activity (EDA) in a clinical dental setting. Skin conductance was continuously recorded in 65 adult patients (age 18-29: n=23; 30-55: n=19; ≥56: n=23) undergoing dental procedures under local anaesthesia at a walk-in dental clinic. Patients were randomly assigned to audiovisual intervention (n=30) or control (n=35), and EDA was measured with a wrist-worn sensor and analyzed in STATISTICA 13.0 using nonparametric tests. Extractions produced significantly elevated mean EDA (mean (M)=10.85 μS, standard deviation (SD)=5.00) compared with non-extraction procedures (M=5.20 μS, SD=5.60; Z=4.25, P<0.001, η2=0.28). Older patients (≥56 years: median (Mdn)=2.49 µS) showed lower EDA than middle-aged patients (30-55 years: Mdn=7.81 µS; H=7.96, P=0.019, η2=0.09), consistent with physiological aging and stress resilience. Procedure duration did not correlate with EDA (r(s)=0.15, P=0.23). Anti-stress ball users showed elevated EDA during extractions (Mdn=13.12 vs. 8.60 μS, Z=-2.22, P=0.026), most plausibly attributable to bilateral hand immobilisation imposed by the study protocol. Among non-extraction procedures, augmented reality glasses (AR) were associated with the lowest median EDA (Mdn=2.35 μS, n=12), followed by music glasses (Mdn=2.73 µS, n=4) and headphones (Mdn=4.01 µS, n=3), though group differences were non-significant (H=1.42, P=0.49). Autonomic arousal was more strongly determined by procedure invasiveness (η2=0.28) than by patient age (η2=0.09), with the invasiveness effect driven primarily by the extraction subgroup. AR glasses were well tolerated and associated with the lowest EDA in non-extraction procedures, warranting evaluation in an adequately powered trial. Adequately powered randomised controlled trials restricted to single procedure types and incorporating validated anxiety scales are required before clinical recommendations can be made.
Clinical relevance
Dental anxiety affects approximately 15% of the general population, yet objective, physiological quantification of autonomic arousal across procedure types, age groups, and distraction modalities in real clinical dental settings remains sparse. This study addresses that gap by employing continuous electrodermal activity (EDA) monitoring as an objective surrogate of sympathetic nervous system activation during routine dental care under local anaesthesia. Clinicians managing anxious dental patients — particularly those selecting or designing distraction-based interventions — will benefit from understanding which procedural and patient-level factors most robustly drive autonomic arousal.
Key findings
1. Procedure invasiveness was the dominant determinant of autonomic arousal: extractions produced significantly higher mean EDA (M=10.85 µS, SD=5.00) compared to non-extraction procedures (M=5.20 µS, SD=5.60; Z=4.25, P<0.001, η²=0.28), representing a large effect size. 2. Patient age significantly modulated EDA: patients ≥56 years exhibited markedly lower median EDA (Mdn=2.49 µS) than middle-aged patients (30–55 years: Mdn=7.81 µS; H=7.96, P=0.019, η²=0.09), consistent with physiological aging and enhanced stress resilience, though this was a medium-to-small effect. 3. Procedure duration showed no statistically significant correlation with EDA (Spearman rs=0.15, P=0.23), indicating that the length of a procedure does not independently predict sympathetic arousal. 4. Anti-stress ball use was paradoxically associated with elevated EDA during extractions (Mdn=13.12 vs. 8.60 µS; Z=−2.22, P=0.026), most plausibly attributable to bilateral hand immobilisation imposed by the study protocol rather than a true anxiogenic effect of the device itself. 5. Among audiovisual distraction modalities in non-extraction procedures, augmented reality (AR) glasses were associated with the lowest median EDA (Mdn=2.35 µS, n=12), followed by music glasses (Mdn=2.73 µS, n=4) and headphones (Mdn=4.01 µS, n=3); however, inter-group differences did not reach statistical significance (H=1.42, P=0.49), likely reflecting insufficient statistical power. 6. The effect of procedure invasiveness (η²=0.28) substantially outweighed that of patient age (η²=0.09) as a driver of autonomic arousal, underscoring that procedural category is the primary modifiable contextual variable for anxiety-reduction targeting.
Practice implications
Clinicians should prioritise anxiety-mitigation strategies — including pre-procedural counselling, pharmacological anxiolysis, or non-pharmacological distraction — most intensively for patients undergoing invasive procedures such as extractions, as these consistently drive the highest objective autonomic arousal regardless of patient age or procedure duration. Augmented reality glasses appear to be well tolerated and were associated with the lowest EDA among non-extraction patients, making them a promising candidate distraction tool for routine restorative or periodontal procedures, though adoption should await adequately powered randomised controlled trials with validated anxiety scales before formal clinical recommendations are established. When designing or evaluating distraction protocols, clinicians must ensure that the intervention itself does not inadvertently restrict patient movement or autonomy (as observed with the anti-stress ball protocol), as physical constraint may counteract any anxiolytic benefit and artificially inflate autonomic measures.