Ambient odors of orange and lavender reduce anxiety and improve mood in a dental office J. Lehrner a,*, G. Marwinski c, S. Lehr b, P. Johren d, L. Deecke a aUniversity Clinic of Neurology, Medical University of Vienna, Austria bDepartment of Medical Statistics, Medical University of Vienna, Austria cPrivate Office, Bochum, Germany dUniversity Witten/Herdecke, Germany Received 27 April 2005 received in revised form 27 May 2005 accepted 24 June 2005 Abstract The goal of this study was to investigate the impact of the essential oils of orange and lavender on anxiety, mood, alertness and calmness in dental patients. Two hundred patients between the ages of 18 and 77 years (half women, half men) were assigned to one of four independent groups. While waiting for dental procedures patients were either stimulated with ambient odor of orange or ambient odor of lavender. These conditions were compared to a music condition and a control condition (no odor, no music). Anxiety, mood, alertness and calmness were assessed while patients waited for dental treatment. Statistical analyses revealed that compared to control condition both ambient odors of orange and lavender reduced anxiety and improved mood in patients waiting for dental treatment. These findings support the previous opinion that odors are capable of altering emotional states and may indicate that the use of odors is helpful in reducing anxiety in dental patients. D 2005 Elsevier Inc. All rights reserved. Keywords: Essential oil of orange Essential oil of lavender Anxiety Mood Aromatherapy 1. Introduction Odors have long been known to be capable of altering the emotional state of humans. Physiological and psycho- logical effects of essential oils have been acknowledged in folk medicine and aromatherapy for a long time [1]. Citrus and lavender fragrances have been particularly attributed with mood enhancing properties by aromathera- pists [2]. In a previous ambient odor study using orange odor in a waiting room of a dentist���s office, we found reduced anxiety and improved mood in female but not in male patients waiting for dental treatment [3]. Early studies demonstrated the sedative nature of lavender [4,5] and in two recent studies [6,7] lavender was shown to improve mood in young subjects however, no data for the clinical setting in a dental office is available for lavender. Given the potential of essential oils of altering psycho- logical states, the goals of the present study were to tackle the important question whether the effect of reducing anxiety and improving mood in a dental office is specific to orange oil or if it can be extended to lavender odor. A second goal was to investigate whether stimuli from other modalities, music for example, have the same effect. For this purpose we set up an experimental trial taking place in the waiting room of a dental office. The setting of a dentist���s waiting room was chosen because previous evidence suggested dental experience to be associated with fear and anxiety [8]. 0031-9384/$ - see front matter D 2005 Elsevier Inc. All rights reserved. doi:10.1016/j.physbeh.2005.06.031 * Corresponding author. Neurologische Universita ��tsklinik, Allgemeines Krankenhaus, Wa ��hringergu ��rtel 18-20, A-1097 Wien, Austria. Tel.: +43 1 40400 3109 fax: +43 1 40400 3141. E-mail address: johann.lehrner@meduniwien.ac.at (J. Lehrner). Physiology & Behavior 86 (2005) 92 ��� 95

2. Materials and methods 2.1. Subjects, experimental design and statistical analyses We included 200 patients between the ages of 18 and 77 years in our study. All subjects gave informed consent for a protocol according to the Helsinki Declaration. Patients were told the purpose of the study was to determine the association between pain and mood. After the experiment, each patient was debriefed about the true nature of the study by the dentist and subsequently provided informed consent. The participants were assigned either to a control group with no odor and no music, or to a music group, or to an orange odor group, or to a lavender odor group, respectively. Patients were selected consecutively in order to control different dental proce- dures (regular check-up, dental hygiene, dental drilling, tooth pulling, pain). First we tested the no odor study group, followed by the music group, then the orange odor study group, and finally the lavender odor study group. Testing started November 2003 and ended in January 2004. As patients were assigned sequentially to the experimental conditions, we assumed that age, pain, nasal disease status, etc. were comparable across conditions. However, due to the season of the year, it was likely that the patient sample contained patients with nasal disease. In order to control for nasal disease status, we screened the patient sample by means of self report for allergies and common cold. The four study groups did not differ regarding frequency of self reported allergies (v2 test, p 0.05) and self reported common cold (v2 test, p 0.05), respectively. See Table 1 for details. Upon arriving, patients were registered and then were handed the questionnaires to be filled-in while waiting for treatment. Importantly, answering the questionnaires was entirely self-paced and dependent only on the speed of patients. We did not measure fill-in time but in no case was it longer than 20 minutes. First, they completed a questionnaire asking for demographic data. The mean age of patients was comparable between the four groups as indicated by analysis of variance ( F(3,194)=1.27, p =0.293). See Table 1. Next they were asked about their current pain using an 11-point Likert scale ranging from 0 (no pain at all) to 10 (unbearable pain). Analysis of variance, for degree of toothache, detected no statistical difference between groups ( F(3,184)=0.74, p =0.534) indicating that all four groups were comparable in terms of pain rating. See Table 1. Patients were next given a German version of the State- Trait Anxiety Inventory (STAI) [9] a self report measure with demonstrated reliability and validity for assessing trait and state anxiety. High scores indicate high self-perceived anxiety. Subsequently, they were given the Mehrdimensionale Befindlichkeitsfragebogen (MDBF) [10] for assessment of current mood, alertness and calmness. Patients had to answer questions on 5-point Likert scales regarding mood, alertness and calmness. Scale reliability (Cronbach���s a) is above 0.9 for all three scales. Higher scores indicate more positive mood, high level of alertness and high level of calmness. Ambient odors of orange and lavender were diffused separately in the waiting room through an electrical dispenser in both odor groups whereas in the control group and the music group no odor was in the air. The dispenser was hidden from the patients view and the system of Voitino Air100 (Krailling, Germany) with constant intermediate concentration was used. The odors were set free from 7:30 a.m. to 6:30 p.m. The waiting room was 16 m2 large. After the change from orange to lavender the odor delivery system was thoroughly cleaned according to standard procedures of the odor delivering system. The natural essential oils of citrus sinensis and lavender supplied by Primavera (Sulzberg, Germany) were used. The main components of the essential oil of orange was determined by gas chromatography to be limonene 95.3% and myrcene 1.88%, all other components were below 1%. The main components of the essential oil of lavender was determined by gas chromatography to be linalylacetate 34.8%, linaloole 30.6%, occimene-cis 5.9%, occimene- trans 3.5%, terpinene-4ol 5.4, lavandulylacetate 3.4%, caryophyllen 4.8%, all other components were below 1%. The gas chromatography data were provided by the delivery company. For the music condition, the compact disk of ������Cafe �� del Mar ��� Music from Ibiza������ was used throughout the study. This particular music is considered up lifting and cheerful, reminding people of vacations and good times. The music was played through the speakers of the dental office in the waiting room situated on the ceiling of the room. The loudness of the music remained constant throughout the study. In order to compare the variable state anxiety between the four ������groups������ an analysis of covariance with the fixed Table 1 Mean, standard deviation, range of scores and frequency for each variable over experimental groups Variables Control (N =51) Music (N =49) Lavender odor (N =48) Orange odor (N =50) Agea 40.4 T 13.3 41.0 T 13.7 41.9 T 14.7 40.2 T 12.4 19���77 23���74 23���74 21���70 Paina 6.3 T 3.1 6.4 T 3.2 6.8 T 3.2 6.6 T 3.5 0���10 0���10 0���10 0���10 Gender (female/male) 26/25 25/24 23/25 24/26 Allergyb (not present/present) 34/13 38/6 38/6 42/5 Common coldc (not present/present) 36/10 30/14 33/13 37/8 a Group effect p 0.05. b v2 test, p 0.05. c v2 test, p 0.05. J. Lehrner et al. / Physiology & Behavior 86 (2005) 92���95 93