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Assessment of general pre and postoperative anxiety in patients undergoing tooth extraction: a prospective study
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British Journal of Oral and Maxillofacial Surgery 52 (2014) 18–23
Assessment of general pre and postoperative anxiety in patients undergoing tooth extraction: a prospective study Pia López-Jornet ∗ , Fabio Camacho-Alonso, Mariano Sanchez-Siles Department of Oral Medicine, Faculty of Medicine and Dentistry, University of Murcia, Spain Received 12 June 2012; accepted 7 January 2013 Available online 26 January 2013
Abstract Our aim was to analyse the amount of anxiety and fear felt before, immediately after, and one week after, dental extraction. We studied 70 patients (35 men and 35 women (mean (SD) age 43 (±10) years), who were listed for dental extraction under local anaesthesia in a private clinic that specialised in oral surgery. Patients were evaluated on 3 consecutive occasions: immediately preoperatively, immediately postoperatively, and 7 days later. Each patient’s anxiety was measured using Spielberger’s State-Trait Anxiety Inventory (Spanish version), the Modified Corah Dental Anxiety Scale (MDAS) and the Dental Fear Survey. There were significant differences in the STAI-Trait scale between before and 7 days after extraction (p = 0.04), and in the MDAS between before and immediately after extraction (p = 0.02), and between immediately after and 7 days after extraction (p = <0.001). The DFS also differed between before and immediately after extraction (p = 0.002), and between immediately and 7 days after extraction (p < 0.001). Dental anxiety immediately after tooth extraction may be influenced by operative techniques (type of anaesthesia, duration of operation, or position of tooth extracted), but anxiety at 7 days after extraction is not. © 2013 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved. Keywords: Anxiety; Dental fear; Oral surgery; Dental treatment
Introduction The most widely accepted concept of anxiety involves a complex pattern of behaviour associated with physiological activation that occurs in response to internal (cognitive and somatic) and external (environmental) stimuli, which patients may experience before or during dental treatment, or both.1–7 Fear and anxiety in dentistry is usually associated with poor oral health, poor oral health-related quality of life, and compromised psychosocial health, including low self-esteem and reduced morale.8–10 McGrath and Bedi11 reported that people with the wost oral health-related quality of life were most commonly among those with high levels
∗ Corresponding author at: Clínica Odontológica Universitaria, Hospital Morales Mesegue, Adv. Marques de los Velez s/n, Murcia 30008, Spain. Tel.: +34 968 398 588. E-mail address: [email protected] (P. López-Jornet).
of dental anxiety. Schuller et al.,12 stated that, compared with people who had little dental fear, people with a great deal of dental fear had more decayed tooth surfaces, decayed teeth, and missing teeth and fewer filled and sound teeth.13 Hägglin et al.,8 also noted that severe dental anxiety was associated with more missing teeth.Dental anxiety is a complex phenomenon affected by several variables.14–18 Pain is often cited as both an aetiological and a maintaining factor in patients’ dental anxiety.19 However, not all patients who experience pain during dental procedures develop disabling dental anxiety,20,21 and not all patients whose overestimation of dental pain is unconfirmed necessarily reduce their recall of past pain or prediction of future pain. Patients’ anxiety may be affected by age, sex, educational standard, and personality. Some studies have reported that people of lower socioeconomic status and with less education have more anxiety, whereas others have reported more dental anxiety in those with better education.14,15,22–25
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http://dx.doi.org/10.1016/j.bjoms.2013.01.004
P. López-Jornet et al. / British Journal of Oral and Maxillofacial Surgery 52 (2014) 18–23
Our hypothesis was that oral surgery is highly stressful for the patient, that the patient’s state of anxiety fluctuates over time, and that studies that have set out to establish qualitative dimensions of fear and anxiety based on assessing patients’ memories have tended to have equivocal findings. Dental anxiety can be assessed successfully with simple self-reported scales. In the present study our objective was to evaluate the degree of anxiety and fear of dental extraction before and immediately after the procedure, and 7 days later, using Spielberger’s State-Trait Anxiety Inventor (STAI) (Spanish version), the Modified Dental Anxiety Scale (MDAS), and the Dental Fear Survey (DFS).
Patients and methods Participants We designed a prospective study with 3 assessment points: before extraction, immediately after, and 7 days later. The study, between January and December 2011, included 90 consecutive patients over the age of 18 years of both sexes who required dental extraction under local anaesthesia and who attended a private dental clinic in Murcia, Spain. All patients were healthy, with no serious medical conditions or blood dyscrasias. Patients who presented with acute infections were excluded, as were those who were unwilling to take part, those with psycho-organic or behavioural disorders, or those with language or cognitive problems. The study was conducted in accordance with the Declaration of Helsinki. The protocol and informed consent form were approved by the University of Murcia Ethics Committee. Informed consent to participate in the study was obtained from all patients. During the first consultation patients were assessed medically, and personal data were recorded (age, race/ethnicity, sex, standard of education, and alcohol and tobacco use) during a semistructured interview. The patients were given routine information and reassurance verbally by the operating surgeon. The teeth were extracted under normal conditions (local anaesthesia only, with no premedication or sedation). The degrees of anxiety and fear were recorded preoperatively. Before patients entered the treatment room they were left alone in a quiet “non-dental” room to fill out the questionnaires. There were three questionnaires: Spielberg’s State-Trait Anxiety Inventory (STAI) and the dental anxiety questionnaires, the Modified Corah Dental Anxiety Scale (MDAS) and the Kleinknecht Dental Fear Scale (DFS). Numerical rating scale The STAI-State form consists of 20 statements, and the answers to these are used to judge a patient’s degree of anxiety at a specific time. The STAI-Trait form consists of a different set of 20 statements, and the answers to these are used to calculate a patient’s underlying (ongoing/personality) degree of anxiety.
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Each statement in the STAI-State is rated on a 4-point scale according to the patient’s agreement with that statement (not at all, somewhat, moderately so, or very much so). This form was used at all 3 time points. Statements in the STAI-Trait are also rated on a 4-point scale. The overall (total) score for STAI ranges from a minimum of 20 to a maximum of 80; STAI scores are commonly classified as “little or no anxiety” (20–37), “moderate anxiety” (38–44), or “extreme anxiety” (45–80). The MDAS is a questionnaire designed specifically to measure anticipatory fear and anxiety. It is made up of 5 questions with multiple choice single-selection responses, whereby the subject chooses the response closest to his or her feelings. Scores range between 5 (no anxiety) and 25 (maximum anxiety); the lower limit for marking subjects with extreme anxiety is 19. The DFS consists of 20 items grouped into 3 dimensions: avoidance, physiological reactions, and specific dental stimuli, according to which a patient’s dental anxiety is assessed on a Likert scale of intensity ranging from 1 (no fear) to 5 (extreme fear). Scores range from 20 (no fear) to 100 (terrified) and the lower limit for an appreciable degree of fear is considered to be 63. Operation Teeth were extracted under local anaesthesia, and all procedures were done by a single experienced surgeon. Each tooth was removed using a standard technique. The duration of operation and type of extraction were recorded by the surgeon. The duration of the intervention was timed from the start of the anaesthetic until the last suture or gauze had been put in place. No antibiotics were prescribed. Patients were given appropriate instructions about the postoperative recovery period. All verbal instructions were reinforced in writing. Each patient was evaluated 3 times: time 1 (T1) = immediately before extraction, time 2 (T2) = immediately afterwards, and time 3 (T3) = 7 days later. Statistical analysis The significances of differences were assessed with the help of the Statistical Package for the Social Sciences (version 12.0, SPSS® Inc., Chicago, IL, USA). A descriptive study was made of each variable. The Kolmogorov–Smirnov normality test and Levene variance homogeneity test were applied. The data showed a normal distribution and so were analysed using parametric tests. The associations between the different qualitative variables were assessed using the chi square test. Student’s t tests for two independent samples and for related samples were used for the study of dental anxiety and fear at different times, and one-way analysis of variance (ANOVA) for more than two samples. In each case we calculated whether the variances were homogeneous. A bivariate analysis was
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P. López-Jornet et al. / British Journal of Oral and Maxillofacial Surgery 52 (2014) 18–23
Table 1 Study of dental anxiety using the State-Trait Anxiety Inventory (STAI) immediately after tooth extraction and 7 days later (n = 70). STAI (State) immediately after tooth extraction
STAI (Trait) immediately after tooth extraction
STAI (State) 7 days later
STAI (Trait) 7 days later
Mean (SD)*
Mean (SD)
Mean (SD)
Mean (SD)
Type of local anaesthesia Block (n = 39) Infiltration (n = 31)
24.46 (5.22) 23.42 (4.84)
Number of injections One (n = 56) Two or more (n = 14)
24.41 (5.22) 22.36 (4.01)
Duration of extraction (min) ≤10 (n = 56) >10 (n = 14)
23.21 (4.71) 27.14 (5.33)
Maxilla/mandible Maxilla (n = 44) Mandible (n = 26)
24.25 (5.42) 23.58 (4.41)
∗
p Value 0.40
p Value 0.008
27.21 (6.22) 23.65 (4.24) 0.18
0.98 25.33 (6.82) 25.29 (4.33)
0.06 24.98 (6.03) 28.21 (2.91)
0.008
0.89 24.66 (6.78) 24.93 (2.33)
0.53 25.54 (5.31) 24.43 (7.66)
0.003 24.09 (4.84) 28.23 (6.14)
0.41
0.30
0.050
0.25 24.29 (5.03) 26.43 (9.44)
0.22 25.98 (5.99) 24.19 (5.41)
p Value
25.26 (7.04) 24.03 (4.79)
25.68 (6.25) 23.86 (3.32)
24.96 (4.37) 28.29 (9.01) 0.59
p Value
0.01 23.32 (5.14) 27.08 (7.02)
Indicates ≤ 0.05
also used for the binary “presence of extreme anxiety (MDAS > 19)” and “presence of extreme fear (DFS > 63)” as the outcome variable. Odds ratios and 95% CI were calculated with exact conditional logistic regression. Probabilities of less than 0.05 were accepted as significant.
Results Of 90 patients invited to take part, 8 refused and a further 12 failed to attend follow-up appointments, so the final sample consisted of 70 patients (35 men and 35 women) with a mean (SD) age of 43 (??) years. Of the 70 patients, 55 (79%) had previously had teeth extracted. Of the 70 extractions, 44 were in the upper maxilla and 26 in the mandible. The mean duration of operation was 10 (range 8–25) min. There were no postoperative complications such as inflammation, swelling, pain, or alveolitis. When the influence of previous experience of extraction was evaluated using STAI, MDAS, and DFS, we found no significant differences in any test. Table 1 shows STAI-State results immediately postoperatively and at 7 days. At T2 the STAI-Trait test showed significant differences in the variables type of local anaesthesia (p = 0.008), duration of operation (p = 0.05), and position of the tooth extracted (p = 0.003). A week later the only significant difference that it showed was the variable position of the tooth extracted (p = 0.01). Table 2 shows results obtained with (MDAS) immediately after extraction. A significant difference was found in the duration of the procedure (p < 0.001), but this difference had disappeared by the 7-day follow-up. Table 3 shows results obtained with the DFS in which a significant difference was found in duration of operation (p < 0.001); this difference was maintained after 7 days (p = 0.002). A logistic regression model (Table 4) for “extreme anxiety (MDAS ≥ 19)” and “extreme fear (DFS ≥ 63)” immediately postoperatively found a significant difference in the
standard of education: MDAS ≥ 19 (p = 0.047) and DFS ≥ 63 (p = 0.025). A further logistic regression model (Table 5) for “extreme anxiety (MDAS ≥ 19)” and “extreme fear (DFS ≥ 63)” at the 7-day follow-up shows a significant difference in the standard of education (p = 0.04), but no differences for any other variable at this time for DFS ≥ 63. Table 6 shows significant differences in the STAI-Trait between T2 and T3 (p = 0.044), in the MDAS between T1 and T2 (p = 0.023) and between T2 and T3 (p = 0.001), and in the DFS between T1 and T2 (p = 0.002) and between T2 and T3 (p = 0.001).
Discussion Surgical extraction or removal of teeth is a common procedure that is rarely life-threatening and has a relatively short recovery period. Nevertheless, the physical and psychological impact makes it a stressful experience.23,24 In this study we have identified variations in the experience using questionnaires completed by patients immediately preoperatively, immediately postoperatively, and 7 days later. In the three tests used – STAI-State, STAI-Trait, MDAS, and DFS – the results from patients who had had previous experiences of dental extraction did not differ significantly from those who had not. This is not surprising, given that Yusa et al.4 confirmed that anxiety associated with extraction of third molars was alleviated by experience. In their experiment with Japanese students who had been listed to have third molars extracted in 2 stages, anxiety scores for the second extraction were significantly lower than those for the first. We found that immediately postoperatively the STAI-Trait detected significant differences in the type of local anaesthetic, the duration of the extraction, and the extraction site. Vallerand et al.5 even stated that trait anxiety is an accurate predictor of postoperative pain and recovery after oral surgery. Scott et al.9 also showed that high
P. López-Jornet et al. / British Journal of Oral and Maxillofacial Surgery 52 (2014) 18–23
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Table 2 Study of dental anxiety using the Modified Dental Anxiety Scale (MADS) immediately after tooth extraction and 7 days later. Data are number (%) and n = 70. MDAS immediately after tooth extraction No (0–5)
Mild (6–11)
Moderate (12–18)
Severe (19–25)
Type of local anaesthesia Block (n = 39) Infiltrative (n = 31)
13 (33) 7 (23)
15 (38) 15 (48)
8 (21) 5 (16)
3 (7.7) 4 (12.9)
Number of injections One (n = 56) Two or more (n = 14)
17 (30) 3 (21)
23 (41) 7 (50)
11(20) 2 (14)
5 (9) 2 (14)
Duration of extraction (min) ≤10 (n = 56) > 10 (n = 14)
18 (32) 2 (14)
26 (46) 4 (29)
5 (9) 8 (57)
7 (13) 0
Maxilla/mandible Maxilla (n = 44) Mandible (n = 26)
12 (27) 8 (31)
17 (39) 13 (50)
8 (18) 5 (19)
7 (16) 0
MDAS 7 days later p Value
No (0–5)
Mild (6–11)
Moderate (12–18)
Severe (19–25)
13 (33) 11 (35)
17 (44) 13 (41.9)
7 (18) 5 (16)
2 (5) 2 (6)
20 (35) 4 (28.5)
24 (43) 6 (42.8)
10 (18) 2 (14)
2 (4) 2 (14)
22 (39) 2 (14)
22 (39) 8 (57)
8 (14) 4 (29)
4 (7) 0
16 (36) 8 (31)
15 (34) 15 (58)
9 (20) 3 (12)
4 (9) 0
0.627
p Value 0.99
0.798
0.48
<0.001
0.16
0.194
0.15
Table 3 Study of dental fear using the Dental Fear Survey (DFS), immediately after tooth extraction and 7days later. Data are number (%) and n = 70. DFS immediately after tooth extraction Mild (0–33.33)
Moderate (33.34–66.66)
Severe (66.67–100)
Type of local anaesthesia Block (n = 39) Infiltration (n = 31)
16 (41) 18 (58)
19 (49) 11 (35)
4 (10) 2 (6)
Number of injections One (n = 56) Two or more (n = 14)
28 (50) 6 (43)
24 (43) 6 (43)
4 (7) 2 (14)
Duration of extraction (min) ≤10 (n = 56) > 10 (n = 14)
32 (57) 2 (14)
18 (32) 12 (86)
6 (11) 04
Maxilla/mandible Maxilla (n = 44) Mandible (n = 26)
23 (52) 11 (42)
16 (36) 14 (54)
5 (11) 1 (4)
DFS 7 days later p Value
Mild (0–33.33)
Moderate (33.34–66.66)
Severe (66.67–100)
21 (54) 21 (68)
15 (38) 8 (26)
3 (8) 2 (6)
35 (63) 7 (50)
18 (32) 5 (36)
3 (5) 2 (14)
38 (68) (29) 10
13 (23) (71)
5 (9) 0
25 (57) 17 (65)
15 (34) 8 (31)
4 (9) 1 (4)
0.36
0.49
0.68
0.45
0.001
0.002
0.28
preoperative anxiety was related to an increase in the amount of pain experienced. According to Armfield et al.,7 dental fear is multidimensional and is associated with the personal and socioeconomic characteristics of the participants as well as with several
p Value
0.64
aspects of oral health care. The number of missing teeth may be an indicator of the number of traumatic experiences; the strength and direction of the association between dental fear and numbers of sound and missing teeth vary considerably according to age. Patients who have never had painful or
Table 4 Logistic regression model for “extreme anxiety” on the Modified Dental Anxiety Scale (MDAS) (≥19) and “extreme fear” on the Dental Fear Survey (DFS) (≥63) immediately after tooth extraction (n = 70). Variables
Extreme anxiety (MDAS ≥ 19) Odds ratio
95% CI
p Value
Odds ratio
95% CI
p Value
Age Sex Educational standard Type of local anaesthesia Number of injections Duration of extraction Maxilla/mandible
2.58 0.72 0.19 1.77 1.70 0.58 0.23
0.46–14.31 0.15–3.51 0.03–0.98 0.36–8.61 0.29–9.84 0.06–5.25 0.02–2.08
0.29 0.69 0.05 0.48 0.55 0.63 0.20
5.32 1.00 0.12 0.61 2.16 0.71 0.78
0.58–48.14 0.18–5.33 0.02–0.77 0.11–3.53 0.35–13.23 0.07–6.62 0.13–4.58
0.14 1.00 0.03 0.58 0.40 0.78 0.78
CI, confidence interval.
Extreme fear (DFS ≥ 63)
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Table 5 Logistic regression model for “extreme anxiety” on the Modified Dental Anxiety Scale (MDAS) (≥19) and “extreme fear” on the Dental Fear Survey (DFS) (≥63) 7 days after tooth extraction (n = 70). Variables
Age Sex Educational standard Type of local anaesthesia Number of injections Duration of extraction Maxilla/mandible
Extreme anxiety (MDAS ≥ 19)
Extreme fear (DFS ≥ 63)
Odds ratio
95% CI
p Value
Odds ratio
95% CI
p Value
3.18 1.00 0.08 1.27 4.50 1.13 0.48
0.31–32.24 0.13–7.52 0.01–0.85 0.16–9.61 0.57–35.21 0.11–11.71 0.04–4.87
0.33 1.00 0.04 0.81 0.15 0.92 0.54
2.12 1.00 0.25 0.61 2.16 1.78 1.56
0.36–2.45 0.18–5.33 0.04–1.41 0.11–3.53 0.35–13.23 0.29–10.78 0.29–8.34
0.40 1.00 0.12 0.58 0.40 0.53 0.60
CI, confidence interval.
Table 6 Study of dental anxiety and fear at different time points (T1 = immediately before tooth extraction, T2 = immediately afterwards, and T3 = 7 days later). Data are mean (SD) and n = 70. Time points
STAI-State
STAI-Trait
MDAS
DFS
T1 T2 T3
24.84 (4.96) 24.00 (5.04) 25.31 (5.81)
24.59 (6.27) 25.63 (5.68)a 24.71 (6.14)b
8.74 (4.51)a 9.91 (5.73)b 8.33 (4.52)a
35.11 (16.11)a 37.84 (17.08)b 34.34 (15.31)a
Groups indicated by different superscripted letters differ significantly. Groups without superscripted letters did not differ significantly from any other. STAI, State-Trait Anxiety Inventory; MDAS, Mofidied Dental Anxiety Scale; and DFS, Dental Fear Survey.
adverse experiences in dentistry may nevertheless acquire dental fear based on indirect experiences.3,5,22 The parts played by the patient’s sex, and contact with dentally fearful relatives deserve additional discussion, as these variables are significantly associated with dental fear.14 We found that standard of education was a protective factor against fear and anxiety in a logistic regression model for “extreme anxiety (MDAS ≥ 19)” and “extreme fear (DFS ≥ 63)” immediately and 7 days after tooth extraction (MDAS ≥ 19 (p = 0.05) and DFS (p = 0.03)). Humphris et al.,17 referred to anxiety as an “aversive psychological construct”, unpleasant to experience and almost always associated with a specific event, which takes time to dissipate. This is supported by our findings as scores improved by the 7-day follow-up. Our patients reported less anxiety a week after the operation in all tests; this may result from rapid recuperation, given that no patients developed any complications. This was a prospective study with a one-week follow-up, and several limitations should be noted. Firstly, any study that lacks a control group has its limits, and the results should be interpreted with caution. Secondly, the follow-up period was rather short. Muglali and Komerik25 studied factors that might have contributed to anxiety before and after oral surgery and found that the difficulty of the procedure does not influence anxiety immediately postoperatively, but does so during the follow-up period, possibly as a result of postoperative complications. The present data, however, show that the immediate emotional impact of extraction under local anaesthesia was relatively modest, perhaps because of the nature of the
operation or because during the follow-up period there were no postoperative complications such as inflammation, bleeding, swelling, pain, or alveolitis. Nevertheless, our results emphasise the importance of psychological factors in assessing and, even better, predicting postoperative recovery after tooth extraction.
Acknowledgement Paula, Liliana y Angelika by data acquisition.
References 1. Rankin JA, Harris MB. Dental anxiety: the patient’s point of view. J Am Dent Assoc 1984;109:43–7. 2. Lago-Méndez L, Diniz-Freitas M, Senra-Rivera C, et al. Dental anxiety before removal of a third molar and association with general trait anxiety. J Oral Maxillofac Surg 2006;64:1404–8. 3. Bergdahl M, Bergdahl J. Temperament and character personality dimensions in patients with dental anxiety. Eur J Oral Sci 2003;111:93–8. 4. Yusa H, Onizawa K, Hori M, et al. Anxiety measurements in university students undergoing third molar extraction. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2004;98:23–6. 5. Vallerand WP, Vallerand AH, Heft M. The effects of postoperative preparatory information on the clinical course following third molar extraction. J Oral Maxillofac Surg 1994;52:1165–71. 6. Liddell A, Locker D. Gender and age differences in attitudes to dental pain and dental control. Community Dent Oral Epidemiol 1997;25:314–8. 7. Armfield JM, Pohjola V, Joukamaa M, et al. Exploring the associations between somatization and dental fear and dental visiting. Eur J Oral Sci 2011;119:288–93.
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17. Humphris GM, Freeman R, Campbell J, et al. Further evidence for the reliability and validity of the modified dental anxiety. Scale Int Dent J 2000;50:367–70. 18. Klages U, Kianifard S, Ulusoy Ö, et al. Anxiety sensitivity as predictor of pain in patients undergoing restorative dental procedures. Community Dent Oral Epidemiol 2006;34:139–45. 19. Zuniga JR. Guidelines for anxiety control and pain management in oral and maxillofacial surgery. J Oral Maxillofac Surg 2000;58(10 (Suppl. 2)):4–7. 20. Ng SK, Chau AW, Leung WK. The effect of pre-operative information in relieving anxiety in oral surgery patients. Community Dent Oral Epidemiol 2004;32:227–35. 21. McNeil DW, Helfer AJ, Weaver BD, et al. Memory of pain and anxiety associated with tooth extraction. J Dent Res 2011;90:220–4. 22. Setteneri S, Tatı F, Fanara G. Gender differences in dental anxiety: is the chair position important? J Contemp Dent Pract 2005;6: 115–22. 23. de Jongh A, van Wijk AJ, Lindeboom JA. Psychological impact of third molar surgery: a 1-month prospective study. J Oral Maxillofac Surg 2011;69:59–65. 24. de Jongh A, Olff M, van Hoolwerff H, et al. Anxiety and post-traumatic stress symptoms following wisdom tooth removal. Behav Res Ther 2008;46:1305–10. 25. Muglali M, Komerik N. Factors related to patients’ anxiety before and after oral surgery. J Oral Maxillofac Surg 2008;66:870–7.
British Journal of Oral and Maxillofacial Surgery 52 (2014) 18–23
Assessment of general pre and postoperative anxiety in patients undergoing tooth extraction: a prospective study Pia López-Jornet ∗ , Fabio Camacho-Alonso, Mariano Sanchez-Siles Department of Oral Medicine, Faculty of Medicine and Dentistry, University of Murcia, Spain Received 12 June 2012; accepted 7 January 2013 Available online 26 January 2013
Abstract Our aim was to analyse the amount of anxiety and fear felt before, immediately after, and one week after, dental extraction. We studied 70 patients (35 men and 35 women (mean (SD) age 43 (±10) years), who were listed for dental extraction under local anaesthesia in a private clinic that specialised in oral surgery. Patients were evaluated on 3 consecutive occasions: immediately preoperatively, immediately postoperatively, and 7 days later. Each patient’s anxiety was measured using Spielberger’s State-Trait Anxiety Inventory (Spanish version), the Modified Corah Dental Anxiety Scale (MDAS) and the Dental Fear Survey. There were significant differences in the STAI-Trait scale between before and 7 days after extraction (p = 0.04), and in the MDAS between before and immediately after extraction (p = 0.02), and between immediately after and 7 days after extraction (p = <0.001). The DFS also differed between before and immediately after extraction (p = 0.002), and between immediately and 7 days after extraction (p < 0.001). Dental anxiety immediately after tooth extraction may be influenced by operative techniques (type of anaesthesia, duration of operation, or position of tooth extracted), but anxiety at 7 days after extraction is not. © 2013 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved. Keywords: Anxiety; Dental fear; Oral surgery; Dental treatment
Introduction The most widely accepted concept of anxiety involves a complex pattern of behaviour associated with physiological activation that occurs in response to internal (cognitive and somatic) and external (environmental) stimuli, which patients may experience before or during dental treatment, or both.1–7 Fear and anxiety in dentistry is usually associated with poor oral health, poor oral health-related quality of life, and compromised psychosocial health, including low self-esteem and reduced morale.8–10 McGrath and Bedi11 reported that people with the wost oral health-related quality of life were most commonly among those with high levels
∗ Corresponding author at: Clínica Odontológica Universitaria, Hospital Morales Mesegue, Adv. Marques de los Velez s/n, Murcia 30008, Spain. Tel.: +34 968 398 588. E-mail address: [email protected] (P. López-Jornet).
of dental anxiety. Schuller et al.,12 stated that, compared with people who had little dental fear, people with a great deal of dental fear had more decayed tooth surfaces, decayed teeth, and missing teeth and fewer filled and sound teeth.13 Hägglin et al.,8 also noted that severe dental anxiety was associated with more missing teeth.Dental anxiety is a complex phenomenon affected by several variables.14–18 Pain is often cited as both an aetiological and a maintaining factor in patients’ dental anxiety.19 However, not all patients who experience pain during dental procedures develop disabling dental anxiety,20,21 and not all patients whose overestimation of dental pain is unconfirmed necessarily reduce their recall of past pain or prediction of future pain. Patients’ anxiety may be affected by age, sex, educational standard, and personality. Some studies have reported that people of lower socioeconomic status and with less education have more anxiety, whereas others have reported more dental anxiety in those with better education.14,15,22–25
0266-4356/$ – see front matter © 2013 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
http://dx.doi.org/10.1016/j.bjoms.2013.01.004
P. López-Jornet et al. / British Journal of Oral and Maxillofacial Surgery 52 (2014) 18–23
Our hypothesis was that oral surgery is highly stressful for the patient, that the patient’s state of anxiety fluctuates over time, and that studies that have set out to establish qualitative dimensions of fear and anxiety based on assessing patients’ memories have tended to have equivocal findings. Dental anxiety can be assessed successfully with simple self-reported scales. In the present study our objective was to evaluate the degree of anxiety and fear of dental extraction before and immediately after the procedure, and 7 days later, using Spielberger’s State-Trait Anxiety Inventor (STAI) (Spanish version), the Modified Dental Anxiety Scale (MDAS), and the Dental Fear Survey (DFS).
Patients and methods Participants We designed a prospective study with 3 assessment points: before extraction, immediately after, and 7 days later. The study, between January and December 2011, included 90 consecutive patients over the age of 18 years of both sexes who required dental extraction under local anaesthesia and who attended a private dental clinic in Murcia, Spain. All patients were healthy, with no serious medical conditions or blood dyscrasias. Patients who presented with acute infections were excluded, as were those who were unwilling to take part, those with psycho-organic or behavioural disorders, or those with language or cognitive problems. The study was conducted in accordance with the Declaration of Helsinki. The protocol and informed consent form were approved by the University of Murcia Ethics Committee. Informed consent to participate in the study was obtained from all patients. During the first consultation patients were assessed medically, and personal data were recorded (age, race/ethnicity, sex, standard of education, and alcohol and tobacco use) during a semistructured interview. The patients were given routine information and reassurance verbally by the operating surgeon. The teeth were extracted under normal conditions (local anaesthesia only, with no premedication or sedation). The degrees of anxiety and fear were recorded preoperatively. Before patients entered the treatment room they were left alone in a quiet “non-dental” room to fill out the questionnaires. There were three questionnaires: Spielberg’s State-Trait Anxiety Inventory (STAI) and the dental anxiety questionnaires, the Modified Corah Dental Anxiety Scale (MDAS) and the Kleinknecht Dental Fear Scale (DFS). Numerical rating scale The STAI-State form consists of 20 statements, and the answers to these are used to judge a patient’s degree of anxiety at a specific time. The STAI-Trait form consists of a different set of 20 statements, and the answers to these are used to calculate a patient’s underlying (ongoing/personality) degree of anxiety.
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Each statement in the STAI-State is rated on a 4-point scale according to the patient’s agreement with that statement (not at all, somewhat, moderately so, or very much so). This form was used at all 3 time points. Statements in the STAI-Trait are also rated on a 4-point scale. The overall (total) score for STAI ranges from a minimum of 20 to a maximum of 80; STAI scores are commonly classified as “little or no anxiety” (20–37), “moderate anxiety” (38–44), or “extreme anxiety” (45–80). The MDAS is a questionnaire designed specifically to measure anticipatory fear and anxiety. It is made up of 5 questions with multiple choice single-selection responses, whereby the subject chooses the response closest to his or her feelings. Scores range between 5 (no anxiety) and 25 (maximum anxiety); the lower limit for marking subjects with extreme anxiety is 19. The DFS consists of 20 items grouped into 3 dimensions: avoidance, physiological reactions, and specific dental stimuli, according to which a patient’s dental anxiety is assessed on a Likert scale of intensity ranging from 1 (no fear) to 5 (extreme fear). Scores range from 20 (no fear) to 100 (terrified) and the lower limit for an appreciable degree of fear is considered to be 63. Operation Teeth were extracted under local anaesthesia, and all procedures were done by a single experienced surgeon. Each tooth was removed using a standard technique. The duration of operation and type of extraction were recorded by the surgeon. The duration of the intervention was timed from the start of the anaesthetic until the last suture or gauze had been put in place. No antibiotics were prescribed. Patients were given appropriate instructions about the postoperative recovery period. All verbal instructions were reinforced in writing. Each patient was evaluated 3 times: time 1 (T1) = immediately before extraction, time 2 (T2) = immediately afterwards, and time 3 (T3) = 7 days later. Statistical analysis The significances of differences were assessed with the help of the Statistical Package for the Social Sciences (version 12.0, SPSS® Inc., Chicago, IL, USA). A descriptive study was made of each variable. The Kolmogorov–Smirnov normality test and Levene variance homogeneity test were applied. The data showed a normal distribution and so were analysed using parametric tests. The associations between the different qualitative variables were assessed using the chi square test. Student’s t tests for two independent samples and for related samples were used for the study of dental anxiety and fear at different times, and one-way analysis of variance (ANOVA) for more than two samples. In each case we calculated whether the variances were homogeneous. A bivariate analysis was
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P. López-Jornet et al. / British Journal of Oral and Maxillofacial Surgery 52 (2014) 18–23
Table 1 Study of dental anxiety using the State-Trait Anxiety Inventory (STAI) immediately after tooth extraction and 7 days later (n = 70). STAI (State) immediately after tooth extraction
STAI (Trait) immediately after tooth extraction
STAI (State) 7 days later
STAI (Trait) 7 days later
Mean (SD)*
Mean (SD)
Mean (SD)
Mean (SD)
Type of local anaesthesia Block (n = 39) Infiltration (n = 31)
24.46 (5.22) 23.42 (4.84)
Number of injections One (n = 56) Two or more (n = 14)
24.41 (5.22) 22.36 (4.01)
Duration of extraction (min) ≤10 (n = 56) >10 (n = 14)
23.21 (4.71) 27.14 (5.33)
Maxilla/mandible Maxilla (n = 44) Mandible (n = 26)
24.25 (5.42) 23.58 (4.41)
∗
p Value 0.40
p Value 0.008
27.21 (6.22) 23.65 (4.24) 0.18
0.98 25.33 (6.82) 25.29 (4.33)
0.06 24.98 (6.03) 28.21 (2.91)
0.008
0.89 24.66 (6.78) 24.93 (2.33)
0.53 25.54 (5.31) 24.43 (7.66)
0.003 24.09 (4.84) 28.23 (6.14)
0.41
0.30
0.050
0.25 24.29 (5.03) 26.43 (9.44)
0.22 25.98 (5.99) 24.19 (5.41)
p Value
25.26 (7.04) 24.03 (4.79)
25.68 (6.25) 23.86 (3.32)
24.96 (4.37) 28.29 (9.01) 0.59
p Value
0.01 23.32 (5.14) 27.08 (7.02)
Indicates ≤ 0.05
also used for the binary “presence of extreme anxiety (MDAS > 19)” and “presence of extreme fear (DFS > 63)” as the outcome variable. Odds ratios and 95% CI were calculated with exact conditional logistic regression. Probabilities of less than 0.05 were accepted as significant.
Results Of 90 patients invited to take part, 8 refused and a further 12 failed to attend follow-up appointments, so the final sample consisted of 70 patients (35 men and 35 women) with a mean (SD) age of 43 (??) years. Of the 70 patients, 55 (79%) had previously had teeth extracted. Of the 70 extractions, 44 were in the upper maxilla and 26 in the mandible. The mean duration of operation was 10 (range 8–25) min. There were no postoperative complications such as inflammation, swelling, pain, or alveolitis. When the influence of previous experience of extraction was evaluated using STAI, MDAS, and DFS, we found no significant differences in any test. Table 1 shows STAI-State results immediately postoperatively and at 7 days. At T2 the STAI-Trait test showed significant differences in the variables type of local anaesthesia (p = 0.008), duration of operation (p = 0.05), and position of the tooth extracted (p = 0.003). A week later the only significant difference that it showed was the variable position of the tooth extracted (p = 0.01). Table 2 shows results obtained with (MDAS) immediately after extraction. A significant difference was found in the duration of the procedure (p < 0.001), but this difference had disappeared by the 7-day follow-up. Table 3 shows results obtained with the DFS in which a significant difference was found in duration of operation (p < 0.001); this difference was maintained after 7 days (p = 0.002). A logistic regression model (Table 4) for “extreme anxiety (MDAS ≥ 19)” and “extreme fear (DFS ≥ 63)” immediately postoperatively found a significant difference in the
standard of education: MDAS ≥ 19 (p = 0.047) and DFS ≥ 63 (p = 0.025). A further logistic regression model (Table 5) for “extreme anxiety (MDAS ≥ 19)” and “extreme fear (DFS ≥ 63)” at the 7-day follow-up shows a significant difference in the standard of education (p = 0.04), but no differences for any other variable at this time for DFS ≥ 63. Table 6 shows significant differences in the STAI-Trait between T2 and T3 (p = 0.044), in the MDAS between T1 and T2 (p = 0.023) and between T2 and T3 (p = 0.001), and in the DFS between T1 and T2 (p = 0.002) and between T2 and T3 (p = 0.001).
Discussion Surgical extraction or removal of teeth is a common procedure that is rarely life-threatening and has a relatively short recovery period. Nevertheless, the physical and psychological impact makes it a stressful experience.23,24 In this study we have identified variations in the experience using questionnaires completed by patients immediately preoperatively, immediately postoperatively, and 7 days later. In the three tests used – STAI-State, STAI-Trait, MDAS, and DFS – the results from patients who had had previous experiences of dental extraction did not differ significantly from those who had not. This is not surprising, given that Yusa et al.4 confirmed that anxiety associated with extraction of third molars was alleviated by experience. In their experiment with Japanese students who had been listed to have third molars extracted in 2 stages, anxiety scores for the second extraction were significantly lower than those for the first. We found that immediately postoperatively the STAI-Trait detected significant differences in the type of local anaesthetic, the duration of the extraction, and the extraction site. Vallerand et al.5 even stated that trait anxiety is an accurate predictor of postoperative pain and recovery after oral surgery. Scott et al.9 also showed that high
P. López-Jornet et al. / British Journal of Oral and Maxillofacial Surgery 52 (2014) 18–23
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Table 2 Study of dental anxiety using the Modified Dental Anxiety Scale (MADS) immediately after tooth extraction and 7 days later. Data are number (%) and n = 70. MDAS immediately after tooth extraction No (0–5)
Mild (6–11)
Moderate (12–18)
Severe (19–25)
Type of local anaesthesia Block (n = 39) Infiltrative (n = 31)
13 (33) 7 (23)
15 (38) 15 (48)
8 (21) 5 (16)
3 (7.7) 4 (12.9)
Number of injections One (n = 56) Two or more (n = 14)
17 (30) 3 (21)
23 (41) 7 (50)
11(20) 2 (14)
5 (9) 2 (14)
Duration of extraction (min) ≤10 (n = 56) > 10 (n = 14)
18 (32) 2 (14)
26 (46) 4 (29)
5 (9) 8 (57)
7 (13) 0
Maxilla/mandible Maxilla (n = 44) Mandible (n = 26)
12 (27) 8 (31)
17 (39) 13 (50)
8 (18) 5 (19)
7 (16) 0
MDAS 7 days later p Value
No (0–5)
Mild (6–11)
Moderate (12–18)
Severe (19–25)
13 (33) 11 (35)
17 (44) 13 (41.9)
7 (18) 5 (16)
2 (5) 2 (6)
20 (35) 4 (28.5)
24 (43) 6 (42.8)
10 (18) 2 (14)
2 (4) 2 (14)
22 (39) 2 (14)
22 (39) 8 (57)
8 (14) 4 (29)
4 (7) 0
16 (36) 8 (31)
15 (34) 15 (58)
9 (20) 3 (12)
4 (9) 0
0.627
p Value 0.99
0.798
0.48
<0.001
0.16
0.194
0.15
Table 3 Study of dental fear using the Dental Fear Survey (DFS), immediately after tooth extraction and 7days later. Data are number (%) and n = 70. DFS immediately after tooth extraction Mild (0–33.33)
Moderate (33.34–66.66)
Severe (66.67–100)
Type of local anaesthesia Block (n = 39) Infiltration (n = 31)
16 (41) 18 (58)
19 (49) 11 (35)
4 (10) 2 (6)
Number of injections One (n = 56) Two or more (n = 14)
28 (50) 6 (43)
24 (43) 6 (43)
4 (7) 2 (14)
Duration of extraction (min) ≤10 (n = 56) > 10 (n = 14)
32 (57) 2 (14)
18 (32) 12 (86)
6 (11) 04
Maxilla/mandible Maxilla (n = 44) Mandible (n = 26)
23 (52) 11 (42)
16 (36) 14 (54)
5 (11) 1 (4)
DFS 7 days later p Value
Mild (0–33.33)
Moderate (33.34–66.66)
Severe (66.67–100)
21 (54) 21 (68)
15 (38) 8 (26)
3 (8) 2 (6)
35 (63) 7 (50)
18 (32) 5 (36)
3 (5) 2 (14)
38 (68) (29) 10
13 (23) (71)
5 (9) 0
25 (57) 17 (65)
15 (34) 8 (31)
4 (9) 1 (4)
0.36
0.49
0.68
0.45
0.001
0.002
0.28
preoperative anxiety was related to an increase in the amount of pain experienced. According to Armfield et al.,7 dental fear is multidimensional and is associated with the personal and socioeconomic characteristics of the participants as well as with several
p Value
0.64
aspects of oral health care. The number of missing teeth may be an indicator of the number of traumatic experiences; the strength and direction of the association between dental fear and numbers of sound and missing teeth vary considerably according to age. Patients who have never had painful or
Table 4 Logistic regression model for “extreme anxiety” on the Modified Dental Anxiety Scale (MDAS) (≥19) and “extreme fear” on the Dental Fear Survey (DFS) (≥63) immediately after tooth extraction (n = 70). Variables
Extreme anxiety (MDAS ≥ 19) Odds ratio
95% CI
p Value
Odds ratio
95% CI
p Value
Age Sex Educational standard Type of local anaesthesia Number of injections Duration of extraction Maxilla/mandible
2.58 0.72 0.19 1.77 1.70 0.58 0.23
0.46–14.31 0.15–3.51 0.03–0.98 0.36–8.61 0.29–9.84 0.06–5.25 0.02–2.08
0.29 0.69 0.05 0.48 0.55 0.63 0.20
5.32 1.00 0.12 0.61 2.16 0.71 0.78
0.58–48.14 0.18–5.33 0.02–0.77 0.11–3.53 0.35–13.23 0.07–6.62 0.13–4.58
0.14 1.00 0.03 0.58 0.40 0.78 0.78
CI, confidence interval.
Extreme fear (DFS ≥ 63)
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Table 5 Logistic regression model for “extreme anxiety” on the Modified Dental Anxiety Scale (MDAS) (≥19) and “extreme fear” on the Dental Fear Survey (DFS) (≥63) 7 days after tooth extraction (n = 70). Variables
Age Sex Educational standard Type of local anaesthesia Number of injections Duration of extraction Maxilla/mandible
Extreme anxiety (MDAS ≥ 19)
Extreme fear (DFS ≥ 63)
Odds ratio
95% CI
p Value
Odds ratio
95% CI
p Value
3.18 1.00 0.08 1.27 4.50 1.13 0.48
0.31–32.24 0.13–7.52 0.01–0.85 0.16–9.61 0.57–35.21 0.11–11.71 0.04–4.87
0.33 1.00 0.04 0.81 0.15 0.92 0.54
2.12 1.00 0.25 0.61 2.16 1.78 1.56
0.36–2.45 0.18–5.33 0.04–1.41 0.11–3.53 0.35–13.23 0.29–10.78 0.29–8.34
0.40 1.00 0.12 0.58 0.40 0.53 0.60
CI, confidence interval.
Table 6 Study of dental anxiety and fear at different time points (T1 = immediately before tooth extraction, T2 = immediately afterwards, and T3 = 7 days later). Data are mean (SD) and n = 70. Time points
STAI-State
STAI-Trait
MDAS
DFS
T1 T2 T3
24.84 (4.96) 24.00 (5.04) 25.31 (5.81)
24.59 (6.27) 25.63 (5.68)a 24.71 (6.14)b
8.74 (4.51)a 9.91 (5.73)b 8.33 (4.52)a
35.11 (16.11)a 37.84 (17.08)b 34.34 (15.31)a
Groups indicated by different superscripted letters differ significantly. Groups without superscripted letters did not differ significantly from any other. STAI, State-Trait Anxiety Inventory; MDAS, Mofidied Dental Anxiety Scale; and DFS, Dental Fear Survey.
adverse experiences in dentistry may nevertheless acquire dental fear based on indirect experiences.3,5,22 The parts played by the patient’s sex, and contact with dentally fearful relatives deserve additional discussion, as these variables are significantly associated with dental fear.14 We found that standard of education was a protective factor against fear and anxiety in a logistic regression model for “extreme anxiety (MDAS ≥ 19)” and “extreme fear (DFS ≥ 63)” immediately and 7 days after tooth extraction (MDAS ≥ 19 (p = 0.05) and DFS (p = 0.03)). Humphris et al.,17 referred to anxiety as an “aversive psychological construct”, unpleasant to experience and almost always associated with a specific event, which takes time to dissipate. This is supported by our findings as scores improved by the 7-day follow-up. Our patients reported less anxiety a week after the operation in all tests; this may result from rapid recuperation, given that no patients developed any complications. This was a prospective study with a one-week follow-up, and several limitations should be noted. Firstly, any study that lacks a control group has its limits, and the results should be interpreted with caution. Secondly, the follow-up period was rather short. Muglali and Komerik25 studied factors that might have contributed to anxiety before and after oral surgery and found that the difficulty of the procedure does not influence anxiety immediately postoperatively, but does so during the follow-up period, possibly as a result of postoperative complications. The present data, however, show that the immediate emotional impact of extraction under local anaesthesia was relatively modest, perhaps because of the nature of the
operation or because during the follow-up period there were no postoperative complications such as inflammation, bleeding, swelling, pain, or alveolitis. Nevertheless, our results emphasise the importance of psychological factors in assessing and, even better, predicting postoperative recovery after tooth extraction.
Acknowledgement Paula, Liliana y Angelika by data acquisition.
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