The fearful patient in routine dental care

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The fearful patient in routine dental care

Carl-Otto Brahm

Senior consultant

Department of Behavioural and Community Dentistry

Institute of Odontology at Sahlgrenska Academy, Göteborg University

Main supervisor: Catharina Hägglin

Senior consultant, Ph.D.
Co-supervisors: Sven Carlsson

Psychologist, Professor emeritus

Jesper Lundgren

Psychologist, Ph.D., senior teacher

Peter Nilsson

Senior consultant, associate professor


Dental fear is a common problem to the dental practitioner. Phobic dental fear requires specialist treatment, and successful methods have been developed to normalize phobic dental patients’ dental health behaviour. However, about 20 % of patients in regular dental care suffer from a significant dental fear without being phobic, which may lead to considerable clinical stress, both for the patient and for the dentist. This problem area has been only sparsely investigated. The aims of this thesis project are to reduce stress reactions experienced by patients and dental professionals during dental treatment and to decrease the risk that the dental fear turns into phobic fear resulting in avoidant behaviour. The studies are based on questionnaires responded to by dental patients and caregivers, and implementation of a structured treatment model regarding dental fear. This project is important in order to map care delivery to patients with non-phobic dental fear, and to develop treatment strategies that are simple and applicable in general dental practice.


Dental fear is a phenomenon that dental behavioural science research has paid attention to during the last 50 years. The fear reaction itself is a response that takes place after being exposed to a real or imagined threat (Öhman 2000). This process is congenital and is important for survival. From this point of view the history of dental fear must be as old as the practice of dentistry and dental fear is still common despite technical and dental educational improvements. In western world the prevalence of dental fear shows only small variations. Moderate dental fear is usually reported in 20 to 25 % of the adult population and severe dental fear in 4-5 % (Milgrom 1988, Hakeberg 1992, Moore 1993, Thomson 1996). The onset of dental fear usually takes place in childhood (Berggren 1984, Öst 1987) and the incidence is reported to peak in the late teen-ages and early adulthood (Locker 1999, Thomson 2000) followed by a decline with age (Lidell 1993, Hägglin 2000). Women are reporting dental fear more frequently than men (Milgrom 1988, Hakeberg 1992, Moore 1993, Skaret 1998). The results are contradictory regarding correlation between socio-economic factors and dental fear (Locker 1991, Hakeberg 1992, Vassend 1993, Skaret 1998, Hägglin 2000).

The concepts dental fear, dental anxiety, and dental phobia are sometimes used synonymously. However a distinction is usually made. The fear reaction is a normal response to a specific stimulus or situation that declines when the stimulus is removed. Anxiety is similar to fear, but an anticipated negative emotional reaction to a hypothetical threat is central (Öhman 2000). Dental phobia in adults can be regarded as a specific phobia in accordance with the DSM-IV (American Psychiatric Association 1994) classification defined as fear of a specific stimulus or situation. The fear is well defined, persistent and irrational. An immediate anxiety response appears in the presence of the phobic stimulus. The fear response is excessive, unreasonable and irrational. The reactions of the phobic stimulus are avoidance, or endurance with intense fear and anxiety. Phobic fear interferes with interaction with other people i.e. social activities or relationships, occupational functioning, and normal routines.

The traditionally recognized etiological pathways to dental fear are through classical conditioning/direct and cognitive learning/indirect processes (Wolpe 1981). Conditioning occurs through experiences of traumatic situations i.e. negative dentist behaviour or pain (Berggren 1984, Milgrom 1988, Moore 1991, Klingberg 1996). Cognitive learning is described as the individual’s negative thoughts of dentistry due to indirect or vicarious learning i.e. through negative information about dentistry or due to observations of other people in dental fearful situations (Berggren 1984, Moore 1991, Milgrom 1995, Berggren 1997). Usually these two pathways coexist during the onset of dental fear. Maintenance of dental fear and concomitant psychosocial effects has been described in a vicious cycle model (Berggren 1984). Once dental fear has been established this can lead to avoidance of dental care that may result in a deteriorated oral status and feelings of shame and inferiority.

According to current knowledge, people with dental fear are a heterogeneous group and the etiological factors are multiple. In addition to classical conditioning and cognitive learning, personality factors, behaviour and temperament have been shown to play an important role. In children the association between temperamental factors and dental fear has been investigated, and it was found that fearful children showed significantly more shyness or negative emotionality than non-fearful children (Klingberg and Broberg 1998, Arnrup 2003). In a majority of adult patients with high dental fear, other extreme fears have been reported (Berggren 1992, Frazer 1988, Schuurs 1988, Hägglin 2001). Similar results were observed in a study of young adults with high dental fear, high levels of agoraphobia, social phobia and simple phobia, suggesting a predisposition to develop anxiety disorders (Locker 2001).

Providing dental health care to patients with high to severe dental fear is a clinical problem. They usually need extra or specialized attention in order to cope with the dental treatment, and there is often a need to refer them to a psychologist, psychiatrist or a specialized dental clinic (De Jong 2005). Behavioural interventions like systematic desensitization have been shown to be superior to general anaesthesia regarding completing training program, completing oral rehabilitation in community dental clinics, frequency of cancellation, and fear reduction (Kvale 2004).

In contrast to the extensive literature on severe dental fear, the knowledge of treatment modalities for patients with a mild to moderate form of dental fear is sparse. General dental practitioners have been reported to be competent in treating adult patients with mild dental anxiety without any complex psychiatric conditions (De Jong 2005). Establishing trust, providing the patient with realistic information and control, and applying a high level of predictability are means that help the moderately anxious patient through the dental treatment. Also teaching the patient coping strategies can be helpful. Other examples are distraction, and relaxation. In order to reduce psychological stress during highly stressful dental treatment, i.e. endodontic treatment and tooth extraction, the use of conscious sedation and hypnosis has been shown to be effective.

Some studies have described the dentist-patient interactions, patient anxiety reduction and satisfaction, including assessment of dentists’ and patients’ behaviours (Corah 1982, O’Shea 1983, Corah 1988, Corah 1989, Rouse 1990, Rouse 1991, Lathi 1992, Lathi 1995, Lathi 1996). However, general dental practitioners’ experiences, attitudes and feelings treating patients with mild to moderate forms of dental fear are still largely unexplored. There are only a few studies investigating this matter (Corah 1982, Corah 1984, O’Shea 1984, Corah 1985, Hakeberg 1992, Arthur 1995, Weiner 1995, Moore 2001, Hill 2008). Some dentists experience stress when treating anxious patients (Hakeberg 1992). The most frequently reported behaviour problems among the patients provoking stress-reactions by the dentists are negative patient statements, such as ‘not appreciating your work’, ‘physically interrupting treatment’, ‘missing/being late’, criticising you as a dentist’, and ‘not cooperative in the chair.


Care delivery in adults with dental fear has been described in dental behavioural science literature. Many studies show patient-perspectives of dental anxiety and reports of dentist-perspectives are rare. The general aim of the present study is to reduce stress reactions experienced by patients and dental professionals during dental treatment. Another aim is to decrease the risk that the dental fear turns into phobic fear resulting in avoidant behaviour. The specific aims are to:

  • 1//Investigate dental caregivers attitudes, feelings and experiences regarding dental fear (study I).

  • 2//Investigate dental caregivers strategies when treating adult patients with dental fear (study I).

  • 3//Investigate impacts of undergraduate training on dental care delivery in fearful patients, and dentists’ postgraduate training, and further educational needs concerning treating patients with dental fear (study I and II).

  • 4//Implementation and evaluation of a structured treatment model in patients with dental fear: dental team perspectives (study III).

  • 5//Implementation and evaluation of a structured treatment model in patients with dental fear: a patient perspective (study IV).


  1. Exploring dentists’ attitudes, experiences and feelings of treating patients with dental fear.

  2. Mapping of dentists’ skills and educational need regarding dental fear.

  3. Dental fear and a structured treatment model: dental team perspectives.

  4. Dental fear and a structured treatment model: patient perspectives.

Material and methods


Studies I and II

The data for the studies I and II have already been collected as a student project at our department, but data have not been analyzed.

From the headquarters of the Association of Public Health Dentists in Sweden 1915 e-mail addresses were received. In total 4300 dentists are registered in the association, but e-mail addresses were only available for less than 50 % (n = 1915). These dental practitioners were asked by e-mail to respond to a web-survey concerning dental fear. A web office ran the logistics, and two reminders were delivered with one week apart. The web survey contained 25 items. 20 of these items were responded to in a 5-grade horizontal Likert scale. The response alternatives were ‘always’, ‘usually’, ‘sometimes’, ‘rarely’ or ‘never’. In the end the responders could leave open comments. The responders were asked about background factors like age, gender, and year of graduation from dental school, time of employment at the current dental office. The responders were also asked about dental training, care delivery to patients with dental anxiety, pre-treatment information seeking, further education in dental behavioural science, pre-treatment preparations, and treatment of patients with dental anxiety. The inclusion criterion used was ‘working as a general dental practitioner treating adult patients’.

Final sample of studies I and II

The web survey was distributed to the 1915 members of the Association of Public Health Dentists. 359 questionnaires were returned due to inaccurate e-mail addresses, giving 1556 responders (81 %). Another 10 e-mails were sent back by auto-response due to vacation, parental leave etc. Also 253 of the responders did not fulfil the inclusion criterion. Altogether 1293 general dental practitioners were left as ‘potential responders’. 889 surveys were returned, and the response rate was finally 69%.

Studies III and IV

Simple and clear strategies are needed when dental care shall be delivered to patients suffering from dental fear. The aim of study III and IV therefore is to implement a structured treatment model in public dental care in order to improve care delivery to patients with dental fear. The structured model includes information, ‘tell-show-do-technique’, relaxation therapy, giving the patient control and when needed conscious sedation using Midazolame and N2O. If the patient suffers from dental fear, the question ‘Do you know you can get professional help with your dental fear?’ should be asked to patients with severe dental fear/phobia. At emergency dental treatment the patient should be asked ‘Do you have regular dental care?’ A negative answer should result in offering the patient referral to specialist treatment or to the public dental care, in order to prevent development of phobic fear.

Ordinary dental treatment is compared to the structured treatment model with regard to dental professionals’ stress levels, and patients’ dental fear and treatment satisfaction. Patients’ levels of dental fear and satisfaction are registered before and after dental treatment. Referrals from public dental care for specialised treatment or from emergency dental clinics to public dental care will be counted before and after implementation of the model. Changes in late cancellation and/or avoidance of dental health care can be recorded by retrospective studying of patient journals.

The dental professionals participating in the study respond to their questionnaire before and after intervention. This allows us to show possible intra individual changes, i.e. reduced stress levels. The structured treatment model applies to the same group of dental professionals, but to different patients (figure 1).

Pilot study

A pilot study will be conducted at the Clinic of Maxillofacial Surgery, Institution of Odontology Jönköping. All dental teams but the one including the main author will participate in the data collection.

During one week, all patients treated at the department will be investigated regarding levels of dental fear and satisfaction with dental treatment. All patients, approximately 100, not only those with dental anxiety will be included.

Part 1.

  1. The team members will respond to a questionnaire regarding stress experienced prior to dental treatment of patients with dental fear, and defining factors causing feelings of stress. This questionnaire also includes a question regarding the team member’s own level of dental fear (‘How do you feel being a dental patient yourself?’). Interviews with the dental teams including dental assistants, dental hygienists, and dentists may precede the construction of the questionnaire.

  2. Information of the present study, asking for a written consent, and a questionnaire, including the psychometric instruments DAS, DFS, and Dental Belief Survey (DBS) or Dental Visit Satisfaction Scale (DVSS), will be sent to the patients by mail prior to the appointment. This questionnaire will be collected before dental treatment.

  3. At the clinic, the patients will be examined and treated without any specific anxiety reducing interventions. Prior to the dental treatment the patient is asked about expected anxiety and pain during treatment.

  4. Directly after dental treatment the patients will respond to the same questionnaire again including questions about experienced anxiety and pain during treatment.

  5. The dental professionals will assess patient behaviour after dental treatment. The dental treatment performed, i.e. doing a root canal, is recorded together with the assessed patient behaviour.

Part 2.

One month later, the structured treatment model is introduced at the Clinic of Maxillofacial Surgery. All fearful patients passing the clinic during one week will be treated according to this model.

  1. The patient screening procedure described in part 1 will be repeated.

  2. After the study is completed the dental professionals respond to the same questionnaire as used in part 1.

All questionnaires will be coded. Any problems coming up within the pilot study will be analysed and may lead to changes in the treatment model.

When the pilot study is completed, some public dental care clinics in the Jönköping County are chosen to participate in the studies where the structured treatment model will be implemented to all teams. A sample of adult patients, age above 20, will consecutively be identified and included in the study. The procedure (part 1 and part 2) in the pilot study is used. All questionnaires will be sent to the research group.


The Dental Anxiety Scale (DAS) is a psychometric instrument assessing distress in the dental situation. It consists of 4 multiple-choice questions scored 1 to 5, giving a score range of 4 to 20. Patients attending dental clinics have an average score of 8 to 9. High dental fear is considered at score 13 and above, and severe dental fear scores for 15 or above (Corah 1969, Corah 1978).

The Dental Fear Survey (DFS) is another instrument measuring different reactions to different stimulations. It consists of 20 multiple-choice questions scored 1 to 5, giving a score range of 20 to 100. Patients attending dental clinics show an average score of 35. High fear scores for 65 or more (Kleinknecht 1978).

The Dental Beliefs Survey (DBS) includes 15 questions regarding patients’ attitudes and beliefs about the interaction between patients and dentists. The items range from 1 to 5 and sum up from 15 (highly positive beliefs) to 75 (highly negative beliefs) (Milgrom 1985).

The Dental Visit Satisfaction Scale (DVSS) measures different aspects of the dentist-patient relationship in the view of the patient. 10 items are scored from 1 to 5, ranging from score 10 (high level of dental fear) to 50 (low level of dental fear) (Corah 1984, Hakeberg 2000).

The Dentist Rating Scale is an instrument used by dental professionals assessing patient behaviour and treatment functioning during dental treatment, scored 1 (complete relaxation and excellent functioning) to 6 (refusal of treatment)(Carlsson 1980, Carlsson 1986). In this research project the Dentist Rating Scale is renamed to the Caregivers rating Scale.

Data analyses

Parametric as well as non-parametric methods will be used in the statistical inference testing. Thus, for comparison between two groups the Student t-test and the Mann-Whitney U-test and between three groups or more Two-Way Analysis of Variance the Kruskal –Wallis One-Way Anova will be applied. For comparison of proportions between groups the Chi-square-test including standardized residual are to be used. For analysing changes over time the paired t-test or the Wilcoxon Signed Rank Test (for continuous variables) or the McNemar Test (for dichotomised variables) will be applied. For estimating relation between two continuous variables the Pearson or Spearman correlation test will be used. For prediction, multiple and logistic regression are to be used and in order to adjust for confounding variables such as age logistic regressions also are to be used.

The pre-chosen level of significance will be p<0.05 in all analyses.


Phobic dental patients are well investigated and documented in the literature. However mild to moderate dental fear are not as thoroughly explored and this is also true when it comes dental caregivers and the relation to their dental fear patients. Thus, this project concerns not only patients with dental fear but also dental caregivers. The psychosocial effects of implementing a structured treatment model treating these patients may be increased wellbeing and quality of life. It may also lead to positive effects among the dental professionals treating patients with dental fear, such as increased levels of control and security. In the end it may reduce occupational stress. The objective with developing a simple treatment model for systematically practice is to reduce the risk that moderately fearful patients develop phobic anxiety and avoid dental care leading to a deteriorated oral status. Thus, in a human as well as national economic perspective the effects of implementing this treatment model may be significant. This project is important in order to map care delivery to patients with non-phobic dental fear, and to develop treatment strategies that are simple and applicable in general dental practice.


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