Aetiology of Dental Phobia
In order to understand the aetiology and development of dental fear and phobia it is relevant to consider psychological and interpersonal aspects of the dental consultation that may affect the patient’s appraisal, feelings and coping in the situation. Theories of how fear reactions are provoked and how individuals cope with facing fearful situations are also important.
Psychological and Interpersonal Aspects of Dental Treatment
Considering the possibilities for real danger, dental treatment should not be especially threatening. However, taking different aspects of dental treatment into consideration, there is reason to believe that dental treatment triggers instinctive survival mechanisms. Darwinian theory indicates that the ability to learn fear may be part of an evolutionary process and that situations that threatened survival in the past are more readily learned to be fearful even today (Nesse and Williams 1994; Marks 1987). In this context, aspects of dental treatment, as well as other medical procedures, may trigger the basic survival mechanism of the fight-or-flight response in the sense that they include sharp objects causing potential pain and bodily damage (e.g. Bracha 2004, 2005; Bracha et al. 2006).
Another aspect of dental treatment is the threatening body position and potential obstruction of free air space during treatment. The dentist often has to perform operations on soft and mineralized human tissue with a high demand for precision. To be able to perform this work, the dentist must have a convenient field of work with good lighting and possibilities to reach any pathological tissues with adequate instruments. This may require a bodily position that is difficult for the fearful patient to accept.
Another essential feature of dental treatment is the intimacy of the oral area. Most people experience shyness when strangers or even acquaintances come too close. In a personal conversation the proper distance between two people is about 1–1.5 metres (Chambers and Abrams 1986). If anyone approaches closer than this, a feeling of unpleasantness or stress easily arises and a defence reaction (e.g. stepping back to reach a comfortable distance) is often observed. To provide dental treatment the dentist must operate within this zone of intimacy.
The mouth has several basic physiological functions. Throughout childhood we experience different kinds of taste. Our taste organs are responsible for identifying food elements and are involved in decision making concerning whether food should be swallowed or expectorated. And patients with enlarged adenoids or other obstructive conditions in the nasopharynx or respiratory system are especially vulnerable to feelings of obstruction of free air space. It is a normal response to react with fear if one feels that these basic functions are threatened.
Dental tissues are highly innervated with pain receptors and almost any dental operation is likely to cause pain in some patients. In spite of recent developments in local anaesthesia and dental equipment and in spite of the trend for less extensive removal of tooth substance, most people experience dental treatment as unpleasant. In a study of a representative sample of the Norwegian adult population, about 20–30 per cent reported their last dental visit as moderately painful or worse and 60 per cent reported having had at least one very painful experience (Vassend 1993). In an Australian study 44–48 per cent of an epidemiological sample reported having experiences of intense pain or considerable discomfort during dental treatment (Armfield 2010). It is a general clinical observation that local anaesthesia is less effective in patients who suffer from extreme fear reactions than in relaxed and confident patients (Fiset et al. 1989; Kaufman, Weinstein and Milgrom 1984) and it may be speculated that fear reactions make the effect of local anaesthesia less potent. Another hypothesis may be that patients for whom it is difficult to achieve adequate anaesthesia (e.g. due to anatomical variations in the mandible) develop dental anxiety mainly for this reason.
The correlation between remembered experiences of pain and dental anxiety is well documented. In one experiment a group of patients with high dental anxiety anticipated more pain during treatment than a group of patients without dental anxiety (Kent 1985). Immediately after treatment, the experience of dental pain was almost the same for the two groups. After three months the patients rated their memory of pain during the dental treatment. The patients with dental anxiety remembered the treatment as being more painful than the patients without dental anxiety. Several retrospective studies have found that patients with dental fear report previous painful dental experiences more often than patients with no dental fear (Bergius et al. 1997; Davey 1989, Vassend 1993; Wright, Lucas and McMurray 1980). It is uncertain whether these reported experiences of pain are cognitive appraisals due to anxiety, or whether the patients actually have experienced more painful episodes during dental treatment. In an experimental study by Bradley, Silakowski and Lang (2007) it was found that individuals reporting high dental fear showed larger and faster startle responses during anticipation of a painful stimulus.
Dental treatment involves some degree of stress in all patients. Experiments have demonstrated that when test subjects feel that they have control over a stressful setting (whether they actually have this control or not), the responses to stress are reduced (e.g. Law, Logan and Baron 1994; Thompson 1981). In the perspective of perceived control it appears important to understand the reason for the event that causes the reaction (Folkman and Lazarus 1984). The dental setting can be very strange for the patient. Without a clear and realistic explanation of the different sequences in dental treatment and the consequences of not being willing to accept treatment, it may be difficult for the patient to understand and accept treatment. Small children do not understand the reasons for dental treatment and the consequences of not receiving treatment. This may be a component in the development of dental anxiety.
In a study by Logan et al. (1991) patients with a high desire for control and an experience of a low feeling of control during treatment, scored significantly higher on a dental fear scale than patients who had a high desire for control and an experience of high control. They also scored higher than patients with a low desire for control. A desire for control is thought to be dependent on a person’s previous experience and his/her personality. The degree of perceived control during treatment is dependent on both the patients’ individual needs and the dental setting (e.g. practical arrangements for stopping the treatment, predictability and the dentist’s mode of treatment). Milgrom, Weinstein and Getz (1995) hypothesized that limited experience of control in the dental treatment situation is a predictor of dental anxiety. A study from Australia confirms that uncontrollability and dangerousness had a strong relationship with high dental fear prevalence (Armfield, Slade and Spencer 2008).
Some dental fear patients describe a desire to scream, to cry, or to run out of the office. They experience these urges as stupid, childish and unlike their regular behaviour and this is frightening. These reactions may be explained, at least partly, as regression phenomena. Regression is a state where the person reacts in an immature way, often linked to the stage where a traumatic event happened (Gill 1972). In a dental setting this means that the adult patient may react emotionally in an infantile way, possibly linked to actual stressful or traumatic experiences in the past. The patient may also have an exaggerated recall of the size of things, for example the size of the injection syringe or the dentist’s hands (Todes 1972).
Christina, 26 years old, reported:
When I sit in the dental chair I feel like I am about five years old and helplessly abandoned. And I recognize these feelings. I was hospitalized for long periods at that age. When my parents were with me, I was happy. They always left me while I was occupied with playing and I did not really observe that they left. When I realized that they were gone, I had these helpless and abandoned feelings and it was extremely frightening.
Niles, 35 years old, claimed:
The dentist told me that my teeth were very bad and that my mother had given me sweets and not taken care of my teeth. I felt this as a strong accusation towards my mother. After this event, I always felt defensive in dental clinics. As soon as I was old enough, I withdrew from contact with dentists and I never told my mother the reason. Even if I intellectually know that the accusation was not true, I still feel a strong distrust against dentists.
Considering different aspects of dental treatment, basic trust between patient and dentist seems to be essential. The patient must trust the dentist to provide him/her with the dental service he/she needs. In all dental clinics difficulties can arise if the dentist’s personality is incompatible with the patient’s and this can lead to problems in trust between them. Thus, it is likely that such incompatible personalities between dentist and patient may contribute to the increasing feeling of stress in both dentist and patient. To prevent this, it is important for the dentist not to regard personality differences as a defeat but to recommend a change of dentist. There are patients whose personality or previous experiences are such that the normal development of trust and confidence in other human beings is interfered with (Miller 1970).
Patients with dental anxiety often report negative experiences with a specific dentist during childhood and they blame this dentist for their dental anxiety. Nevertheless, there must be many patients who have been treated by the same dentist without developing dental anxiety. It may be that persons with specific personality traits experience negative stimuli as more threatening and therefore have an enhanced risk of developing dental fear.
In a number of studies factors related to personality have been shown to predispose for dental anxiety, for instance: impulsivity in temperament (Stenebrand, Boman and Hakeberg 2012); alexitymia (Pohjola et al. 2011a); general anxiety and depressive disorder (Pohjola et al. 2011b); and neuroticism (Vassend, Røysamb and Nielsen 2011).
Elements of the Fear Reaction
When exposed to a dangerous situation, humans will experience an emergency reaction of the body including different elements of fear: cognitive, physical, emotional and behavioural. These elements will now be described.
The cognitive element
This element includes expectations of specific impending harm. When the cognitive element triggers a fear reaction people will automatically exaggerate the actual danger, but subsequent cognitive assessment will usually produce the correct and suitable reaction to the danger in a specific situation. The context in which it occurs is important for the cognitive assessment. A lion’s roar will alert us if we are on an African safari. If the lion is behind bars at a zoo in our home town, the reaction will be different.
Lazarus (1966) broke down the individual construction of a potentially dangerous situation into a series of steps: primary appraisal, secondary appraisal and reappraisal. He described cognitive processing as analogous to the process of taking a photograph. Specific settings like type of lens, focus and so on, have an enormous effect on the information in the photograph. In the same manner through selective attention our expectations, interests and concerns will affect the perception of the event (Rosenhan and Seligman 1989). We conceptualize a situation in terms of how it may affect or threaten us. This is illustrated when eye witnesses are asked to describe a specific situation. The eye witnesses ‘see’ different situations even if they observed the same event and it may be impossible to reconstruct the ‘true’ event.
This ‘first shot’ of information observed by the threatened subject is called the primary appraisal. Potentially dangerous situations are often treated as a threat in the primary appraisal. Normally a reappraisal will occur and the threat may be defined as false. A person who is very anxious or afraid will not be able to make these reappraisals and will therefore treat all ‘false’ threats as being dangerous. This may explain the clinical observation that patients with dental anxiety often seem to be unable to distinguish between unpleasantness and pain during dental treatment. In a cognitive approach these thoughts arising in the primary appraisal are essential.
Fear reactions lead to many bodily changes, both internally and externally. In a matter of seconds after a perceived danger, our body’s resources are mobilized involuntarily (Rosenhan and Seligman 1989). The external changes are prominent in many animals; the octopus changes from green to red when it is afraid. Human appearance may also change. Physiological reactions can often lead to altered body language and different facial expressions (Lanzetta and Orr 1980).
The purpose of the internal changes is to enable us to deal with the dangerous situation observed or perceived. Fear and stress cause an increase in muscular tension and activate the autonomic nervous system. All forms of behavioural therapy based on relaxation aim to subdue this muscle activation.
These are the elements we describe when we talk about our feelings of fear such as feelings of dread, terror, panic or just a creeping sensation or tight stomach. We are generally most conscious of the emotional elements, whereas the cognitive and physiological emergency reactions are usually outside of awareness and therefore less readily observed.
How the fearful person behaves, decides the consequences of the fear reaction. Thus, in order to act empathically with patients suffering from dental fear it is important to understand such reactions.
When the individual, through the elements of the fear reaction, appraises the situation as fear provoking, he/she will react voluntarily to do something about the object or situation that provokes the fear. Research distinguishes between four major behavioural strategies: