A Practice-Based Comparison of Brief Cognitive

Regular Article Received: February 17, 2010 Accepted after revision: September 1, 2010 Published online: March 3, 2011

Psychother Psychosom 2011;80:159–165 DOI: 10.1159/000320977

A Practice-Based Comparison of Brief Cognitive Behavioural Treatment, Two Kinds of Hypnosis and General Anaesthesia in Dental Phobia André Wannemueller a Peter Joehren b Simon Haug b Mathias Hatting b Karin Elsesser a Gudrun Sartory a  

 

 

a

 

 

 

Department of Clinical Psychology, University of Wuppertal, Wuppertal, and b Dental Clinic, St. Augusta Hospital, Bochum, Germany  

 

Key Words Dental phobia ⴢ Cognitive behavioural treatment ⴢ Hypnosis

Abstract Background: A practice-based study was carried out to assess the comparative effectiveness and acceptability of standardised hypnosis, hypnosis with individualised imagery, cognitive behavioural treatment (CBT) and general anaesthesia (GA) in the treatment of dental phobia. Methods: A 4-group design was used with 4 repeated measurement occasions. Of an initial total of 137 dental phobics, 77 completed the study with sample sizes of between 14 and 29 patients in the 4 groups. Participants completed questionnaires of dental anxiety at the beginning of the trial, before and after the first dental appointment and again before the second dental appointment a week later. Results: Standardised hypnosis evidenced a significantly higher rate of premature termination of treatment than CBT. The completer analysis showed a significant reduction of dental anxiety after CBT and individualised hypnosis compared to the GA condition. The intent-to-treat analysis showed significant improvement only after CBT. Conclusions: The results suggest that CBT is the treatment of choice in dental phobia when taking both effectiveness and acceptability into account. Copyright © 2011 S. Karger AG, Basel

© 2011 S. Karger AG, Basel 0033–3190/11/0803–0159$38.00/0 Fax +41 61 306 12 34 E-Mail [email protected] www.karger.com

Accessible online at: www.karger.com/pps

Introduction

Fear of dental treatment is common with 20% of adults indicating that they are highly anxious and 5% avoiding dental treatment altogether [1]. Dental phobia has an early onset at a mean age of 12 years [2] and poses, apart from the emotional discomfort, a considerable health risk. Whereas 1 or 2 teeth require treatment in the general population at any time, 8–9 decaying teeth were found during an examination in dental phobics [3]. A number of psychological treatment approaches have been found to be effective in dental phobia, among them systematic desensitisation [4], modelling [5] and imaginal exposure [6]. Whereas relaxation on its own does not reduce phobic anxiety, its use as a coping reaction is considerably successful in combating first bodily signs of anxiety (i.e., anxiety management training), or in the presence of the phobic stimulus [7]. Thus, a single session of stress management training combined with imaginal exposure proved more effective than benzodiazepine administered before dental treatment [3]. Exposure was found to be successful irrespective of whether phobics attended to the stimuli or were distracted from them [8]. Finally, a comparison between exposure to video-recorded dental scenes with either relaxation or cognitive treatment found both equally successful [9]. A meta-analysis of behavioural interventions in dental phobia attested Prof. Gudrun Sartory, PhD Department of Clinical Psychology, University of Wuppertal Max-Horkheimer-Strasse 20 DE–42119 Wuppertal (Germany) Tel. +49 202 439 2722, Fax +49 202 439 3031, E-Mail sartory @ uni-wuppertal.de

medium to large effect sizes with 77% of patients showing a long-term benefit [10]. While cognitive behavioural treatment (CBT) proved successful, psychologists are frequently not available for an immediate administration. Instead the use of hypnosis administered by dentists themselves prior to dental treatment found a following. Originally employed to counter dental treatment pain, hypnosis has also been reported to be successful in combating dental phobia in a number of single-case studies [11]. A standardised hypnosis (StandHyp) procedure was developed and is commercially available on CD to be played during dental treatment [12]. However, a comparison between the taped version and live hypnosis showed the latter to be more anxiety reducing [13]. Exposure to videotaped dental scenes in combination with muscle relaxation aided by EMG feedback was found to be more effective than hypnotherapy [14], but the high drop-out rate in the hypnotherapy condition of this study left a group size of only 5 (out of 11) for the final comparison. Anxiety-reducing treatments should both bring relief in the phobia-related situation and reduce anxiety in anticipation of the next encounter with it. The latter has rarely been investigated in detail in treatment studies of people with dental phobia. Instead, long-term studies usually enumerate the number of dental appointments over a number of years following treatment. The aim of the present study was to compare the effect of a number of treatment approaches not only on the immediate symptom relief but also on anticipatory anxiety before the subsequent treatment session. Phobia-related measures were therefore taken not only the day after the first dental treatment but also a week later immediately before the second dental treatment. Two types of hypnosis were compared, the standardised CD version and another kind employing personal imagery. The 2 conditions were compared with 2 sessions of CBT and a further group receiving general anaesthesia (GA). The assessment of acceptability of the treatments was based on the drop-out rate in the 4 conditions. We expected CBT to be more effective and enduring than GA and, to a lesser extent, the 2 hypnosis conditions.

Subjects and Methods Participants Participants were 137 individuals (47 male, 90 female; mean age = 38.5 years, SD = 11.8) who suffered from dental phobia according to DSM-IV criteria [15]. They constituted consecutive referrals of patients with dental phobia to the Dental Clinic of the Augusta Hospital in Bochum, Germany. A small psychological

160

Psychother Psychosom 2011;80:159–165

unit is attached to the clinic with clinical psychologists from the Department of Clinical Psychology of the University of Wuppertal specialising in the treatment of dental phobia. Exclusion criteria were dental treatment within the previous year (apart from emergency treatment) and use of anxiolytic medication. The initial standardised assessment interview (diagnostic interview of mental disorders) [16] revealed the following comorbid disorders: additional specific phobia (n = 32), social phobia (n = 26), agoraphobia (n = 16), generalised anxiety disorder (n = 7) and affective disorder (n = 7). Design and Procedure There were 4 treatment conditions, i.e. CBT, individualised hypnosis (IndHyp), StandHyp and GA. CBT was carried out by postgraduate clinical psychologists and the 2 types of hypnosis treatment were carried out by dental practitioners specialising in the respective methods. Upon entering the dental clinic, patients were given a questionnaire of dental anxiety (HAF, see below). If their score exceeded the cut-off for dental phobia, they were asked to enter the research programme. The receptionist of the dental clinic allocated patients to conditions according to the availability of the respective therapist with the exception of GA which was only given on specific demand by the participants. A contributory payment of EUR 50.00 was required for the StandHyp treatment, whereas the other treatments were without additional payment to the patients. [In Germany, CBT is covered by the national health insurance, whereas hypnosis has to be paid for by the patients themselves. IndHyp was carried out by a dental doctoral student (S.H.) as part of his doctoral thesis project therefore administering the treatment for free. GA is also covered by the health insurance.] Following dental X-ray investigation to assess the number of decayed teeth and psychological assessment to ascertain the diagnosis, measurements were made on 4 occasions, the first of which (M1) at the beginning of the trial, the second one (M2) before and the third one (M3) the day after the first dental treatment. The fourth and final assessment (M4) took place before the second dental treatment session a week later. Treatments Cognitive Behavioural Treatment. The 2 sessions of CBT lasted for 60 and 50 min, respectively, and were similar to the treatment reported by Thom et al. [3]. Initially, patients received psychoeducation about symptoms of anxiety, were then introduced to progressive muscle relaxation and received a CD with relaxation instructions to practice at home. Dysfunctional thoughts were explored and replaced by coping thoughts which were written down. Finally, a fear hierarchy was established and patients were given imaginal exposure while being instructed to counteract anxiety reactions by relaxation and coping thoughts. A week later, patients were shown videotaped dental scenes while being instructed to use relaxation and coping thoughts to combat anxiety reactions. CBT was carried out in the psychology unit on the floor below the dental clinic. Standardised Hypnosis. A week before dental treatment, patients were introduced to hypnosis and were given a CD with standard hypnotic suggestions [17] which they were asked to listen to at home. Thirty minutes before the first dental treatment, patients were placed in the dental chair to start listening to the CD via headphones and continued to do so throughout dental treatment.

Wannemueller /Joehren /Haug /Hatting / Elsesser /Sartory  

 

 

 

 

 

Individualised Hypnosis. A week before dental treatment, patients were given information and a CD about hypnosis. The dentist explored activities which the patients considered pleasant. Twenty minutes before the first dental treatment session, patients were placed in the dental chair and the hypnotising dentist induced hypnosis by relaxation suggestions and focusing the attention of the patient on vivid imagery of the previously explored pleasant activity (e.g. ‘you feel increasingly exhilarated riding the horse, nothing can frighten you any more’). The suggestions continued for the first 10 min into dental treatment by another dentist with the hypnotising dentist remaining with the patient throughout. General Anaesthesia. Patients were informed as to the risks of GA and asked to give their written consent in an initial session. They received a combination of hypnotics (propofol) and analgesics intravenously and remained under narcosis throughout dental treatment. Measures Hierarchical Anxiety Questionnaire [18]. Patients rate how much anxiety they would experience in 11 hierarchically ordered phobic situations from 1 to 5. The cut-off score for dental phobia is considered to be 35 [19]. An internal consistency index of 0.80 (Cronbach’s ␣) has been reported [20]. Dental Anxiety Scale (German Version Translated by the Authors) [21]. This most frequently used questionnaire in dental anxiety research is the main outcome measure of the present study and consists of 4 items related to dental treatment. Scores range from 4 to 20. Corah et al. [22] reported a mean score of 9.07 in 2,103 non-selected participants. Dental phobic patients had a mean score of 17.20 (SD = 1.80). A score of 15 is considered the cut-off for being phobic. An internal consistency index of 0.64 (Cronbach’s ␣) was found for this scale [20]. Dental Cognitions Questionnaire (German Version Translated by the Authors) [23]. This self-rating questionnaire consists of 38 negative cognitions (beliefs and self-statements) related to dental treatment which patients are asked to endorse if they occur to them during dental treatment. The frequency of negative cognitions (score range = 0–38) is summed. Dental phobics were found to have a significantly higher number of negative cognitions than controls. Data of a previous study yielded a Cronbach’s ␣ of 0.90 [20]. Revised Iowa Dental Control Index (German Version Translated by the Authors) [24]. This self-rating questionnaire consists of 9 items, 5 of which concern the desire for control (Cronbach’s ␣ 1 0.78–0.79) and the other 4 perceived control during dental treatment (Cronbach’s ␣ 1 0.75–0.80). Items are rated from 1 (none) to 5 (totally) and summed. Dental patients with a high desire for control coupled with a low feeling of control reported high levels of dental distress compared to low scorers [25]. State-Trait Anxiety Inventory (German Version by Laux et al.) [26]. Probands indicate the degree to which each of 20 statements describing emotional states applies to them at present (state) and during the last 2 weeks (trait version). Scores range from 20 (no anxiety) to 80 (high anxiety) (Cronbach’s ␣ 1 0.90) [26]. Subjective Ratings of Treatment Effectiveness and Treatment Dependence. At the end of the final assessment (M4), participants were asked to rate how effective they considered their treatment of dental anxiety from 0 (not at all) to 3 (highly effective) and whether they would become distressed if the treatment was not

Cognitive Behavioural Treatment vs. Hypnosis in Dental Phobia

available during the next dental treatment from 0 (not at all) to 4 (highly distressed). Data Analysis Owing to day-to-day clinical management problems, a number of data were missing. Initially univariate ANOVAs were carried out with regard to each variable for M1 to assess the baseline comparability of groups. ANOVAs with a 4 ! 4 factorial design (group ! measurement occasion) were then carried out for each variable. Afterwards, ANCOVAs partialling out M1 from the following measurements were carried out to determine the respective treatment success of the 4 conditions. M3 and M4 are the 2 main outcome measurements. M3 occurred the day after the first dental treatment and shows the immediate treatment success, whereas M4 occurred a week later before the second dental appointment and indicates whether the treatment success is enduring. Finally, owing to the high number of drop-outs an intent-totreat analysis was carried out in regard to the main outcome measure [Dental Anxiety Scale (DAS)] with the last observation being carried forward.

Results

Figure 1 displays the flow diagram of the participating patients and drop-out rates. Figure 2 shows the survival rate of patients over measurement occasions. Groups differed with regard to drop-out rate with the StandHyp group showing a significantly higher drop-out rate than the CBT (Wilcoxon-Gehan Z = 7.20, p ! 0.007) and the GA group (Wilcoxon-Gehan Z = 10.4, p ! 0.001). The latter also showed a lower drop-out rate than the IndHyp group (p ! 0.05). Completers had stayed away from dental treatment longer (mean = 9.4 years, SD = 7.8) than dropouts (mean = 6.4 years, SD = 5.6) [F(1, 125) = 5.68; p ! 0.02]. Comparing the different groups, they did not differ significantly from each other with regard to any of the demographic and dental characteristics (p 1 0.10) (table 1). The number of participants with complete data is detailed in table 2 with regard to each psychological variable. Unless otherwise indicated, there were no significant group differences at M1. The DAS scores diminished over measurement occasions differentially for groups [F(9, 168) = 3.68, p ! 0.01, ␩2 = 0.16]. As shown in table 2, the CBT condition resulted in greater improvement than GA, with the other 2 groups in between. Using a cut-off score of 13, groups differed in number of still highly anxious patients at M3 (␹2 = 12.89, p ! 0.005, d.f. = 3), with the number of anxious versus non-anxious patients being for CBT: 6/11, for StandHyp: 12/3, for IndHyp: 8/6, and for GA: 14/6. CBT was significantly more successful than the StandHyp Psychother Psychosom 2011;80:159–165

161

Assessed for eligibility (n = 182) Not meeting inclusion criteria (n = 21) Other reasons (n = 24)

Enrollment (n = 137) Allocation StandHyp (n = 38)

IndHyp (n = 30)

Lost to 1st DA (n = 5)

CBT (n = 27)

Lost to 1st DA (n = 19)

Lost to 1st DA (n = 8)

Lost to 1st DA (n = 6)

GA (n = 42)

Given reasons:

Given reasons:

Given reasons:

Given reasons:

None given (n = 5)

None given (n = 7) Too expensive (n = 7) Need for GA (n = 1) Refusal to participate (n = 1) Other reasons (n = 3)

None given (n = 8)

None given (n = 4) Refusal to participate (n = 1) Other reasons (n = 1)

First dental appointment (1st DA) n = 22

N = 19

n = 22

n = 36

Lost to 2nd DA (n = 3)

Lost to 2nd DA (n = 4)

Lost to 2nd DA (n = 8)

Lost to 2nd DA (n = 7)

Given reasons:

Given reasons:

Given reasons:

Given reasons:

None given (n = 2) No further treatment necessary (n = 1)

None given (n = 4)

None given (n = 8)

None given (n = 4) No further treatment necessary (n = 2) Other reasons (n = 1)

Second dental appointment (2nd DA) n = 19

n = 15

n = 14

n = 29

Fig. 1. Flow diagram of patients entering

the study.

CBT

StandHyp

GA

IndHyp

100

Survival (%)

90 80 70 60 50 40 30 M1

M2

M3

M4

Fig. 2. Survival rate of participants. The 4 measurement points

refer to the beginning of the trial (M1), before (M2) and the day after (M3) the first dental appointment and before the second dental appointment (M4) a week later.

162

Psychother Psychosom 2011;80:159–165

condition (Fisher exact test, p ! 0.003) and the GA condition (Fisher exact test, p ! 0.02). The intent-to-treat ANOVA (fig. 3) yielded a significant group effect [F(3, 133) = 3.56, p ! 0.02, ␩2 = 0.07] and a significant measurement occasion effect [F(3, 399) = 50.22, p ! 0.01, ␩2 = 0.27]. Separate group comparisons showed significantly greater improvement in the CBT compared to all other groups (CBT vs. IndHyp: p ! 0.05; CBT vs. StandHyp: p ! 0.01; CBT vs. GA: p ! 0.005). None of the other group comparisons showed significant differences. As regards the Dental Cognitions Questionnaire frequency of negative cognitions, the CBT group indicated a significantly lower number of dysfunctional thoughts than the StandHyp group at M1 (p ! 0.05). As shown in table 2, the GA and StandHyp conditions showed higher scores than the CBT and the IndHyp conditions at the end of treatment. Wannemueller /Joehren /Haug /Hatting / Elsesser /Sartory  

 

 

 

 

 

Table 1. Group means and SDs (in parentheses) of demographic variables and dental characteristics of the 4 treatment groups

CBT (n = 19) Age, years Sex ratio (women/men) Avoidance of dental treatment, years Decayed teeth Missing teeth HAF (screening)

n

41.42 (13.00) 10/9 9.08 (7.72) 7.83 (4.67) 9.47 (8.19) 45.50 (7.88)

18 18 17 19

StandHyp (n = 15)

n

39.53 (9.01) 12/3 9.40 (9.03) 7.20 (6.50) 6.87 (6.03) 46.46 (5.52)

15 15 15 14

IndHyp (n = 14)

n

41.93 (7.16) 9/5 9.19 (6.53) 8.71 (4.83) 7.31 (6.26) 44.50 (7.90)

13 14 13 13

GA (n = 29) 34.76 (12.30) 16/13 9.59 (8.09) 11.04 (7.04) 5.58 (3.06) 45.50 (6.93)

n

27 21 26 27

Table 2. Group means and SDs (in parentheses) of psychological variables of measurement occasion 1 and adjusted means of measurement occasions 3 and 4 of the 4 treatment groups

CBT (n = 19)

n

StandHyp (n = 15)

n

IndHyp (n = 14)

n

GA (n = 29)

n

M1 M3 M4

17.03 (2.58) 12.29a 12.61a

15

17.68 (2.00) 14.01a 14.56a, b

14

18.00 (2.48) 14.40a, b 13.76a

14

16.75 (2.73) 16.44b 16.26b

17

M1 M3 M4

16.27a (4.96) 10.22a 10.14a

15

24.57b (5.89) 14.86a, b 17.68b

14

M1 M3 M4

21.02 (4.15) 19.90a, b 19.72

11

22.33 (2.31) 20.73b 20.70

12

IDCI (perceived control)

M1 M3 M4

7.55 (2.34) 12.34a 12.42a

11

7.15 (2.73) 11.1a, b 10.27b

13

State anxiety (STAI)

M1 M3 M4

44.30a 42.00 51.97

10

59.25b (9.04) 31.91a 59.25

12

Trait anxiety (STAI)

M1 M3 M4

39.80 (9.32) 38.70 37.61

10

43.00 (9.51) 41.10 39.68

13

Efficacy rating

M1

2.31 (0.48)a

13

1.27 (0.90)b

11

2.11 (1.05)a, b

9

2.20 (0.79)a, b 10

Treatment dependence

M4

1.31 (1.03)a

13

1.55 (1.44)a, b 11

2.22 (1.30)a, b

9

2.80 (0.92)b

DAS

DCQ (frequency)

IDCI (desired control)

55 5.47** 3.89*

21.54a, b (8.68) 13 11.99a 9.79a

22.76a, b (7.09) 17 18.71b 16.77b

21.08 (3.38) 17.81a 18.12

13

19.69 (3.90) 20.29b 19.63

13

7.54 (3.17) 11.20a, b 11.10a, b

13

7.33 (2.37) 9.29b 9.22b

12

54 4.85** 5.02** 44 2.60 44 2.50 3.71*

59.31b (11.32) 13 44.08b 54.46

62.18b (10.88) 11 49.55b 48.77

37.55 (8.15) 41.39 39.39

48.33 (11.06) 39.03 39.23

11

Covar. d.f. F ratios

41 7.56**

12

10

Different superscripts refer to significant group differences between CBT, StandHyp, IndHyp and GA conditions. DCQ = Dental Cognitions Questionnaire; IDCI = Revised Iowa Dental Control Index; STAI = State-Trait Anxiety Inventory.

If considering desired control of the Revised Iowa Dental Control Index, the IndHyp group indicated less desire for control than the GA and the StandHyp groups at M3, whereas regarding perceived control of the Revised Iowa Dental Control Index, the CBT condition exhibited higher perceived control than the GA condition and the StandHyp group (p ! 0.04).

CBT showed a lower group mean than the other groups for the state anxiety scale of the State-Trait Anxiety Inventory [F(3, 42) = 5.86, p ! 0.05] at M1. However, there were no significant group effects with regard to the trait anxiety scale of the State-Trait Anxiety Inventory. As to subjective rating of treatment efficacy and dependence, the CBT group considered their treatment as

Cognitive Behavioural Treatment vs. Hypnosis in Dental Phobia

Psychother Psychosom 2011;80:159–165

163

DAS (intent to treat)

CBT

StandHyp

GA

IndHyp

19 18 17 16 15 14 13 12 11 10 M1

M2

M3

M4

Fig. 3. Adjusted group means of the intent-to-treat analysis of the

DAS over the 4 measurement occasions [beginning of the trial (M1), before (M2) and the day after (M3) the first dental appointment and before the second dental appointment (M4) a week later].

being more efficient than the StandHyp group (p ! 0.02) and the GA group indicated higher distress than the CBT group with regard to further dependence upon the anxiolytic intervention [F(3, 39) = 3.58, p ! 0.03].

Discussion

The intent-to-treat analysis, i.e., combining acceptability and effectiveness of treatment, indicated that CBT was the only treatment which resulted in improvement of dental phobia with none of the other treatments differing significantly. Regarding the completer analysis, results also indicated that CBT was more efficacious than the StandHyp treatment. According to the DAS, only 35% of the CBT group were still to be considered markedly anxious compared to 80% of the StandHyp group at the end of treatment. The StandHyp group also evidenced more dysfunctional cognitions and less perceived control than the CBT group. Additionally, the StandHyp group considered their treatment to be less successful and more patients terminated treatment prematurely compared to the CBT group. It is conceivable that the additional fee of EUR 50.00, not required in any other condition, led to the immediate drop-out of 50% of participants. This difference among the treatment conditions and the lack of a formalised randomisation as required in the case of randomised controlled treatment trials [27] has to be considered a major limitation of this study. However, the additional fee is required in general practice when using this type of hypnosis. Introducing it in the present study is 164

Psychother Psychosom 2011;80:159–165

therefore also a test of the acceptability of this intervention in dental practice. Finally, the additional fee cannot account for the poor treatment outcome in participants remaining in this group. CBT was also more successful than GA with more participants in the GA group, namely 70%, still being markedly anxious at the end of treatment. The GA group also indicated higher distress if they were unable to receive a GA at the next dental treatment. There was no difference in drop-out rate between the two groups. Next to the CBT condition, the IndHyp condition showed the best results, albeit with a high drop-out rate of 54% (compared to 30% in the CBT condition). It is likely that the context of the 2 treatments contributed to the divergent drop-out rates. Hypnosis was carried out in the dental chair which requires the patients to enter the most fear-evoking environment before being administered any anxiety-relieving treatment. In contrast, patients received CBT in the psychology unit for dental fear and were prepared for the entry into the dental treatment room. IndHyp was also markedly more successful than StandHyp. The 2 methods differed with regard to the suggestions and the method of administration. At this stage, it is unclear whether the success of the individualised hypnosis is due to the use of idiosyncratically pleasant imagery or its administration via a hypnotist. The latter has previously been found to be more effective than a CD [13]. Summarising, the results suggest that playing a CD with standardised hypnotic suggestions does not show any benefit in the treatment of dental phobia. In contrast, the hypnotic suggestion of personalised pleasant imagery was similarly successful and enduring as CBT. However, the individualised hypnotic suggestions were characterised by low acceptance. It is likely to be due to patients having to enter the highly fear-evoking dental treatment situation ahead of and in order to receiving the anxietyrelieving treatment.

References

1 Getka EJ, Glass C: Behavioural and cognitive-behavioural approaches to reduction of dental anxiety. Behav Ther 1992; 23: 433– 448. 2 Öst LG: Age of onset in different phobias. J Abnorm Psychol 1987;96:223–229. 3 Thom A, Sartory G, Jöhren P: Comparison between one-session psychological treatment and benzodiazepine in dental phobia. J Consult Clin Psychol 2000;68:378–387.

Wannemueller /Joehren /Haug /Hatting / Elsesser /Sartory  

 

 

 

 

 

4 Smith TA, Kroeger RF, Lyon HE, Mullins MR: Evaluating a behavioral method to manage dental fear: a 2-year study of dental practices. J Am Dent Assoc 1990; 121: 525– 530. 5 Melamed BG, Haws RR, Heiby E, Glick J: Use of filmed modelling to reduce uncooperative behaviour of children during dental treatment. J Dent Res 1975;54:797–801. 6 Mathews A, Rezin V: Treatment of dental fears by imaginal flooding and rehearsal of coping behaviour. Behav Res Ther 1977; 15: 321–328. 7 Ning L, Lidell A: The effect of concordance in the treatment of clients with dental anxiety. Behav Res Ther 1991;17:97–110. 8 Schmid-Leuz B, Elsesser K, Lohrmann T, Jöhren P, Sartory G: Attention focussing versus distraction during exposure in dental phobia. Behav Res Ther 2007;45:2691–2703. 9 Berggren U, Hakeberg M, Carlsson SG: Relaxation vs cognitively oriented therapies for dental fear. J Dent Res 2000;79:1645–1651. 10 Kvale G, Berggren U, Milgrom P: Dental fear in adults: a meta-analysis of behavioral interventions. Community Dent Oral Epidemiol 2004;32:250–264. 11 Gow MA: Hypnosis with a 31-year-old female with dental phobia requiring an emergency extraction. Contemp Hypn 2006; 23 (suppl 2):83–91.

Cognitive Behavioural Treatment vs. Hypnosis in Dental Phobia

12 Schmierer A: Die Anwendung von Entspannungstonbändern in der zahnärztlichen Praxis. Zahnärztl Prax 1991; 42(suppl 8): 286–288. 13 Saletu A, Knaus A, Gritsch F, Gruber G, Anderer P, Walter H: Vergleichende Untersuchungen von Hypnose mit Hilfe einer CD versus Live-Hypnose in der zahnärztlichen Behandlung. Hypn Kogn 2002;19:167–176. 14 Hammarstrand G, Berggren U, Hakeberg M: Psychophysiological therapy vs hypnotherapy in the treatment of patients with dental phobia. Eur J Oral Sci 1995;103:399–404. 15 American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, ed 4, revised. Washington, American Psychiatric Association, 2000. 16 Schneider S, Margraf J: Diagnostisches Interview bei psychischen Störungen (DIPS für DSM-IV-TR), ed 3. Berlin, Springer, 2006. 17 Schmierer A: Möglichkeiten der Hypnose für die zahnärztliche Praxis. Zahnärztl Prax 1990;5:178–181. 18 Jöhren P: Validierung eines Fragebogens zur Erkennung von Zahnbehandlungsangst. Zahnärztl Welt Ref 1999;108:775–778. 19 Jöhren P, Sartory G: Zahnbehandlungsangst, Zahnbehandlungsphobie. Hannover, Schlüterer, 2002. 20 Sartory G, Heinen R, Pundt I, Jöhren P: Predictors of behavioural avoidance in dental phobia: the role of gender, dysfunctional cognitions and the need for control. Anx Stress Coping 2006;19:279–291.

21 Corah NL: Development of dental anxiety scale. J Dent Res 1969;48:596–602. 22 Corah NL, Gale EL, Illig SJ: Assessment of a dental anxiety scale. J Am Dent Assoc 1978; 97:816–819. 23 De Jong A, Muris P, Ter Horst G, Schoenmakers N: Negative cognitions of dental phobics: reliability and validity of Dental Cognitions Questionnaire. Behav Res Ther 1995;5:507–515. 24 Brunsman BA, Logan HL, Patil RR, Baron RS: The development and validation of the revised Iowa Dental Control Index (IDCI). Pers Individ Dif 2003;34:1113–1128. 25 Logan HL, Baron RS, Keeley K, Law A, Stein S: Desired control and felt control as mediators of stress in a dental setting. Health Psychol 1991;10:352–359. 26 Laux L, Glanzmann P, Schaffner P, Spielberger CD: Das State-Trait-Angst-Inventar. Weinheim, Beltz, 1981. 27 Mohr DC, Spring B, Freedland KE, Beckner V, Arean P, Hollon SD, Ockene J, Kaplan R: The selection and design of control conditions for randomized controlled trials of psychological interventions. Psychother Psychosom 2009;78:275–284.

Psychother Psychosom 2011;80:159–165

165