Aromatherapy and anxiety in a dental waiting room: an N-of-1 crossover study

Francesca Imbrogno; Henrique Borges; Cláudia Barbosa; Joana Sardinha; Joana Lameiro; Tânia Soares

doi:10.62741/ahrj.v3i2.178

Authors

Francesca Imbrogno Faculty of Health Sciences, University Fernando Pessoa https://orcid.org/0009-0001-6596-2978
Henrique Borges FP-I3ID, FP-BHS, Faculty of Health Sciences, University Fernando Pessoa, Porto, Portugal https://orcid.org/0000-0002-0563-6441
Cláudia Barbosa FP-I3ID, FP-BHS, Faculty of Health Sciences, University Fernando Pessoa, Porto, Portugal  RISE-Health, Faculty of Health Sciences, University Fernando Pessoa,  Fernando Pessoa Teaching and Culture Foundation, Porto, Portugal https://orcid.org/0000-0002-2191-2338
Joana Sardinha FP-I3ID, FP-BHS, Faculty of Health Sciences, University Fernando Pessoa, Porto, Portugal https://orcid.org/0000-0002-4835-0267
Joana Lameiro FP-I3ID, FP-BHS, Faculty of Health Sciences, University Fernando Pessoa, Porto, Portugal https://orcid.org/0000-0002-3749-4812
Tânia Soares FP-I3ID, FP-BHS, Faculty of Health Sciences, University Fernando Pessoa, Porto, Portugal https://orcid.org/0000-0003-2859-8801

DOI:

https://doi.org/10.62741/ahrj.v3i2.178

Keywords:

aromatherapy, lavender, essential oils, dental anxiety, dental fear

Abstract

Introduction: Dental fear and anxiety are highly prevalent conditions that negatively affect participant attendance, cooperation and clinical outcomes. Non-pharmacological interventions, such as aromatherapy, have been proposed as adjunctive strategies to reduce anxiety in dental settings.

Objectives: To evaluate the effect of lavender (Lavandula angustifolia) essential oil inhalation on dental anxiety and physiological parameters in a clinical context.

Methodology: A single-subject (N-of-1) crossover study (ABBA design) was conducted. One participant attended four clinical sessions under alternating lavender (2%) and placebo conditions. Anxiety levels were assessed using the State-Trait Anxiety Inventory (STAI-Y1 and STAI-Y2) and the Modified Dental Anxiety Scale (MDAS). Physiological parameters, including blood pressure, heart rate and oxygen saturation, were recorded before and after each session. Data were analyzed descriptively.

Results:

A reduction in state anxiety (STAI-Y1) was observed across all sessions, regardless of condition, with consistent decreases in scores, while MDAS scores showed variable changes and were interpreted as exploratory. Physiological parameters demonstrated no consistent or clinically relevant differences between conditions.

Conclusion: Lavender aromatherapy may contribute to reduced perceived dental anxiety; however, similar improvements observed under placebo conditions suggest a relevant contextual or placebo effect. These findings highlight the need for further controlled studies to clarify the specific clinical effectiveness of aromatherapy in dental practice

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