A decision tree logically displaying alternative actions in the management of root-filled teeth with apical periodontitis
6.3 Variation in Endodontic Retreatment Decision Making
In a benchmark
, experimental study, Reit and Gröndahl [1
] confronted 35 dental officers from the Public Dental Health Organization in Sweden with 33 endodontically treated teeth with radiographic signs of persistent apical periodontitis. In no case was the same option suggested unanimously by all observers. The number of teeth selected for therapy (surgical or nonsurgical retreatment or extraction) had an inter examiner range of 7–26 teeth. Petersson et al. [2
] scrutinized 1094 treatment plans including radiographs submitted to the Swedish dental insurance system by general practitioners. In 874 root-filled teeth, a periapical radiolucency was diagnosed by the authors. According to the treatment plan, extraction, periapical surgery and conventional retreatment were suggested for 23%, 3% and 20%, respectively. However, for the remaining 472 cases (54%), no intervention was prescribed. In another study, Petersson et al. [3
] re-examined a sample of 351 individuals from a randomly selected cohort of 1302 persons radiographically examined 11 years earlier. It was found that 33 (40%) of the endodontically treated teeth with periapical bone lesions at first examination had been retreated or extracted, while the remaining 49 teeth had received no radiographically detectable treatment. This quandary continues to attract attention from various aspects among researchers, and the overall conclusion is that there is no consensus [4
]. In particular, the constantly repeated observation that the mere diagnosis of apical periodontitis does not consistently lead to clinical action has attracted special attention [6
The implementation of dental implants to replace a compromised tooth has made the issue even more marked and controversial which has been highlighted in numerous publications in recent years [7
6.4 Variation in Medical and Dental Care
Variation in health-care procedures
was recognized early, at the beginning of the twentieth century. In a classical study [9
] of 1000 11-year-old schoolchildren in New York City, it was found that 650 children had undergone tonsillectomy. The remaining 350 children were sent to a group of physicians. One hundred and fifty-eight children were selected for tonsillectomy. Those rejected (192) were sent to another group of physicians, and 88 of them were then suggested for tonsillectomy. After that, the remaining children were examined by a third group of physicians, and then only 65 children remained for whom tonsillectomy had not been suggested. At that point the study was interrupted owing to a shortage of physicians to consult.
Variation in care is a real challenge to many areas within medicine and health care [10
] as well as dentistry [14
Already in 1984 Eddy [10
] condensed the worrisome situation:
Uncertainty creeps into medical practice through every pore. Whether a physician is defining a disease, making a diagnosis, selecting a procedure, observing outcomes, assessing probabilities, assigning preferences, or putting it all together, he is walking on a very slippery terrain. It is difficult for nonphysicians, and for many physicians, to appreciate how complex these tasks are, how poorly we understand them, and how easy it is for honest people to come to different conclusions.
Owing to its intricacy, clinical decision making has attracted interdisciplinary attention. In addition to interest from health professionals, philosophers, psychologists and economists have also contributed . Two main spheres of research and thinking can be identified: descriptive and prescriptive. Descriptive projects aim at mapping out and explaining how clinicians reason and make decisions. Prescriptive, or normative, projects, on the other hand, are involved with how decisions should or ought to be made.
6.5 Clinical Decision Making: Descriptive Projects
In studies of clinical reasoning
, several models have been suggested and used [17
]. Some investigators have focused on the artistic, or intuitive, aspects of clinical practice [12
In the tradition of “judgement analysis” [19
], researchers have tried to reveal the pieces of information or “cues”, used at conscious or unconscious levels, that influence a person’s decision making policy. This approach has been applied in several domains [20
] including judgements of third molar removal [21
]. In a series of investigations, Kahneman and Tversky [22
] explored a proposition that people most often rely on a small number of heuristic principles to make decisions. Their gathered important insights into human thinking and decision making were admirably summarized the other year by Nobel laureate Kahneman [23
6.5.1 Descriptive Projects on Endodontic Retreatment Decision Making
Attempts have been made to explain the observed
variation in the management of periapical lesions in endodontically treated teeth. Since several studies have demonstrated large interindividual variation in radiographic interpretation of the periapical area [24
], it has been hypothesized that variation in retreatment decisions might be regarded as a function of diagnostic variation. However, nor studies among general practitioners [25
] or specialists [5
] have given support to this idea. Rawski et al. [26
] applied the above-mentioned “judgement analysis” model. The complexity and multiplicity of factors present in different studies of the phenomenon have rendered it difficult to present a coherent model to explain the observed variation. But the diagnostic difficulties, timing and the question of what should be regarded as healthy and diseased, as well as several other factors, partly explain the large variation among dentists regarding retreatment decision making [6
126.96.36.199 The Praxis Concept
The Strindberg [27
] criterion of
classifying the results of endodontic treatment into “success” and “failure” represents an “ideal” concept of disease. According to Juul Jensen [28
], such criterion is demarcated and made explicit by a formal definition. However, by no way are all our concepts defined in such a precise way. Still these concepts exist. They exist in the sense that we use them. Such concepts are referred to as “praxis concepts” by Juul Jensen [28
]. In search of a theory that could, at least partly, explain the variation in retreatment decision making, a “praxis concept” of periapical health and disease following root canal treatment was generated and tested in a series of written case simulation design studies [29
In this “praxis concept”, it was proposed that dentists consider periapical health and disease, not as either/or situations, but as states on a continuous scale. On this scale a major lesion represents a more serious condition than a smaller one. Variation between decision makers could then be regarded as the result of the individuals’ selection of differing cut-off points on the scale for prescribing retreatment. The investigations gave support to the view that a periapical health continuum is the basis of a praxis concept. Factors unrelated to the disease per se (costs, technical quality of root filling, access problems) also seemed to contribute to the final placement of the cut-off point. These studies also emphasized the subjective influence of personal values on the selection of retreatment criterion. Similar patterns among clinicians’ root canal retreatment strategies were also found among dental students in Saudi Arabia [32
] and general practitioners and specialists in Australia [7
6.5.2 Personal Values
According to the praxis
concept, a dentist’s values influence the recommendation of endodontic retreatment. The concept of value is multidimensional, but it seems sound to assume that there is a close connection between an individual’s values and his or her value judgements. It has been suggested that one may apprehend values in acts of preferring [33
]. This means that when faced with a choice, the values of an individual are reflected in his preference behaviour. For example, the value of health is given in preferring it to disease.
The subjective values of endodontic health states in root-filled teeth were investigated among dental students [35
] and specialists in endodontics [30
In these studies, students and endodontists were asked to judge a health state of a root-filled incisor with no signs of periapical pathology, and one health state where a periapical radiolucency was diagnosed. The two health states were placed on a utility scale extending from “perfect pulpal and periapical health” (value = 1) to “loss of the tooth” (value = 0). Large interindividual variations in value judgements were found for both situations. Nevertheless, most raters assigned higher values to a situation were no signs of pathology were present compared to a situation with a periapical lesion present. Nevertheless, these studies failed to show any significant correlation between the retreatment prescriptions and the elicited values. However, the assessment of value judgements is a complex task, and the methods of eliciting them and the reliability and validity of obtained values may be questioned [36
6.5.3 The Benefit of Endodontic Retreatment
According to von Wright [37
is beneficial to a being when the doing or having or happening of this thing affects the good of that being favourably. He suggests that when the being in question is a human being, the phrase “the good of a being” can be understood in two different ways: in terms of welfare and in terms of health. This means that a treatment procedure is beneficial to a patient if it is in some way conducive to his welfare (or well-being), or if it is conducive to his (bodily or mental) health or both [38
From a dental health point of view, a patient will benefit from endodontic retreatment if he or she moves from a health state with a periapical inflammation to a post-retreatment situation where the lesion has healed. If the health states are placed on a utility scale, the subjective benefit of endodontic retreatment can be defined as the distance between the two states (Fig. 6.2
). Presumably, endodontic retreatment will contribute to a person’s well-being and health in proportion to the individual length of the distance between the health states.
An individual may benefit from endodontic retreatment by moving from a state with an asymptomatic lesion to a state where the lesion has healed. The numerical difference in assigned utility values can be defined as the “subjective benefit of retreatment”
In an investigation involving 16 endodontists, it was found that the assessment of “retreatment benefit” was subjected to substantial interindividual variation [30
]. This was due above all to the experts’ deviations in their judgement of the value of the persistent periapical lesion. The findings clearly demonstrated that the “benefit” of endodontic retreatment varies among individuals and highlight the necessity of “consumer” influence in clinical decision making. From a subjective point of view, some patients will benefit much more from endodontic retreatment than others. It also suggests that the value-laden terms “success” and “failure” are meaningful only in the clinical patient-dentist context. Both doctors’ and patients’ values will influence the decision making process.
Today patient autonomy is widely regarded as a primary ethical principle, emphasizing the importance of paying attention to the values and preferences of the individual patient in any prescriptive theories of clinical decision making.
6.6 Clinical Decision Making: Prescriptive Projects
Prescriptive projects in clinical decision making are fundamentally an issue of ethics. Prescriptive ethics, or normative ethics (syn), is the branch of philosophical ethics that investigates the set of questions that arise when considering how one ought to act, morally speaking. Prescriptive ethics is consequently distinct from descriptive ethics, as the latter is an empirical investigation of people’s moral beliefs or values. To put it another way, descriptive ethics would be concerned with determining what proportion of dentists believe that endodontic retreatment should be performed, while prescriptive ethics is concerned with whether it is correct or not to hold such a belief.
6.6.1 Ethics: What It Is
Ethics deals with that
which is good or bad, what should or should not be done and what characteristics make us better or worse as individual human beings. The central question in normative ethics concerns the right procedure; its role is to clarify how ethical questions should be managed, i.e. what should be done in a certain situation and what should be avoided [39
]. A course of action can be wrong on ethical grounds in two different ways. Either there is something offensive in the course of action itself that makes it unacceptable, regardless of the expected consequences of the action, e.g. because those concerned are not treated with respect and dignity, or that it violates basic human rights. Or the expected negative consequences exceed the expected benefit, and thus the action is disallowed. If there is profound objection in principle against the course of action, then there is no cause to reason further and weigh the positive and negative consequences. In other cases, these consequences should be considered.
Ethics in health care is concerned primarily with how the individual patient should be treated, i.e. what is beneficial and what is harmful to the patient, respectively. Several patient-related interests become relevant. Normally and particularly issues regarding health and well-being are central to dental ethics. But also, questions regarding and autonomy and integrity are highly relevant. Ethics in dentistry, however, covers more than the individual patient. Effectiveness, priority and fairness are also relevant aspects of ethics, as are questions about how to weigh up the interests of the patient against research interests (see Chapter “Consequences”).
The following four principles, which are well established in biomedical ethics, are often presented as a basis for ethics in health and medical (and dental) care [40
The do-good principle means that one should try to help the patient by satisfying his or her (medical and basic human) needs.
The do no harm principle means that one should avoid harming the patient. One should, for example, avoid taking unjustifiable risks.
The autonomy principle means that one should respect the patient’s right to self-determination, which implies that one must keep patients informed and guarantee them the right to decline the treatment being offered.
The principle of fairness or justice means that patients with similar needs should be treated similarly. That is, it is the patient’s treatment need which should determine the course of action, not—for example—the patient’s cultural background, gender, financial or social standing.
The principles in themselves do not suggest an order of priority in cases of conflict. One can easily imagine situations where the treatment which is most likely to improve the patient’s dental health is at the same time associated with greater risk than other treatment options. In such a case, which principle should be applied, the “do-good” or the “do no harm” principle? A similar conflict can arise between the “do-good” principle and the autonomy principle, in cases where the patient does not want to accept the treatment, which the dentist recommends. However, the four principles are not intended as a total ethics package for solving ethical problems. The purpose is more to remind us of core ethical principles, which should be taken into account and guide us in clinical decision making.
6.6.2 The “Strindberg System”
In endodontics, the system
of dichotomizing the outcome of root canal treatment into “success” and “failure” launched by Strindberg [27
] has achieved paradigmatic status as a normative guide to clinical action. According to Strindberg [27
], the only satisfactory post-treatment situation, after a predetermined healing period, combines a symptom-free patient with a normal periradicular situation. Only cases fulfilling these criteria were classified as “successes”, and all others as “failures”.
Consequently, when a new or persistent periapical lesion is diagnosed in an endodontically treated tooth, the Strindberg system prescribes retreatment (or extraction). The Strindberg system is exclusively based on biology and can be perceived as dogmatic and inflexible. Although generally accepted in academic institutions, available studies and experience indicate a weak position among general practitioners [3
6.6.3 Expected Utility Theory
One of the most highly
developed normative decision making models is the “
expected utility theory” (EUT). For reviews see Hargreaves Heap et al. [34
] and Bacharach and Hurley [43
]. The philosophical foundation of the model is to be found in classical utilitarianism [44
], while its mathematical origins are even older [46
]. The advent of modern EUT is associated with the influential work of von Neumann and Morgenstern [33
] which made some of the psychological assumptions of utilitarianism redundant. During the last 70 years, EUT has prospered mainly in economics and the social sciences. The theory was introduced to medicine by Ledley and Lusted [47
]. “Clinical decision analysis” has received much attention in medicine and also in dentistry [48
EUT prescribes that the problem should be structured as a “decision tree”, which (i) logically displays available actions and their possible consequences. Then (ii) the listed outcomes are assessed regarding probabilities and subjective values (“utility”). After this (iii) the weighed sum (expected utility) of each strategy is computed, and (iv) the action with the highest sum is chosen.
Reit and Gröndahl [1
] approached the management of periapical lesions in endodontically treated teeth from a decision analytic point of view. Even if EUT may be questioned as a normative theory, it does point out two essential components of a basis for making clinical decisions: empirical facts and subjective values. Later these authors drew attention to the fact that the critical information needed for the analysis were either not available (utility values) or very uncertain (outcome probabilities) [49
6.6.4 Evidence-Based Decision Making
In more recent years
, the development of the concept of evidence-based medicine/evidence-based dentistry has come to supplement and to some extent replace the formal clinical decision analysis [50
Evidence-based medicine is “the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients”. This well-known definition emanates from the highly cited report published by David L. Sackett and collaborators in the 1996 British Medical Journal
While evidence-based medicine/evidence-based dentistry basically is concerned with the efficiency of the clinical procedures that we apply to treat our patients, in order to achieve the best possible outcome for each patient based on the best knowledge and available resources the concept has not always been generally agreed upon and the concept has nowadays, in some instances, been given a wider meaning and has become something of a buzzword. However, during recent years hundreds of books and thousands of articles have been published using this conception. In addition, websites and various other channels of information issued by researchers, clinicians and organizations have been released on this new concept in the clinical practice of health care including dentistry.
Bergenholtz and Kvist [52
] reviewed the essence of the concepts and its impact on endodontics. Like Reit and Gröndahl [49
], 30 years earlier, the authors reported that evidence-based data on various outcomes associated with apical periodontitis in root-filled teeth is largely lacking, and also patients’ preferences are difficult to estimate.
6.6.5 Autonomy and Information
The principle of autonomy is highly relevant to diagnosis and treatment of apical periodontitis in root-filled teeth. What should patients decide? What information should the dentist provide and should any information be withheld from the patient?
The mouth is an intimate part of the body. It is therefore reasonable to assume that it is important for people to make their own decisions about their teeth, not least with respect to any treatment. In order to make informed decisions about their own dental care, patients require relevant information. In circumstances where there is a lack of knowledge about the expected benefits of different treatment options, it is difficult to provide information, which offers the patient a basis for decision making. It is also difficult to analyse the value of different options from a general point of view. It is therefore important from both an individual patient and a community perspective that research is conducted to improve our knowledge of the effects of the various options for root-filled teeth with apical periodontitis. In the future, this will allow the clinician to offer better information to patients and thus for the patient to assess various action alternatives.
As indicated by the many epidemiological studies and the experiments on endodontic retreatment decision making among clinicians, asymptomatic apical periodontitis associated with root-filled teeth is often not considered as an indication for retreatment, and hence these teeth are left without treatment. Is this wrong? Is the dentist under an obligation to inform the patient of the situation? Furthermore, a not inconsiderable portion of the cases is a consequence from previously improper root canal treatments. Should the dentist inform the patient about previously inadequate treatment? From the perspective of autonomy, the answer to these questions seems obvious. Anyone wanting such information about their dental status should have the right to this if the information is found during an examination at a dental appointment.
A difficulty is that some patients do not wish to receive such information, i.e. they prefer not to know unless the information has a clear and direct bearing on their health and/or well-being. Consequently, the dentist needs to ascertain beforehand what attitude the patient has to such information, in order to show due consideration to both patients who want to be fully informed and those who do not. To ask the patient whether he wishes to receive such information is reasonably no adequate strategy because the patient may draw the conclusion that the dentist now has some information or would otherwise not have asked.
It may be challenging to have to inform a patient that previous treatment has not been successful, as there is a risk of singling out oneself or a colleague in a negative way. This is sometimes unavoidable if the patient is to receive relevant information. In the case of diagnosing someone else’s “failure”, it is important to combine objectivity in presenting the information with a respectful attitude, since it is usually impossible to fully appreciate under what circumstances the treatment was accomplished.
188.8.131.52 Monitors and Blunters
Kristina is a 62-year-old teacher, and I have just told her that the X-ray of her upper left first molar does exhibit a periapical radiolucency and an inadequate root filling. The root canal treatment was done 6 years ago. I tell her that this indicates a persisting root canal infection and that it might become symptomatic sooner or later. I suggest a CBCT examination for better imaging, verifying the diagnosis and support for decision making. I am telling her that a minor surgery might be needed to solve the problem. Then I tell her that I will contact her again when I have looked at the CBCT results and suggest a treatment plan. “Will it be painful to do a surgery?”, she asks slightly surprised. “No it is a standard procedure done with local anaesthesia at our clinic”, I answer. “Do you have any further questions”, I ask. “No, I trust you to tell me what I need to know”, she answers before rising from chair and leaving.
In the same week, I see John, a 50-year-old shop owner, for a check-up of a root canal treatment of a lower first molar I finished 1 year ago. The X-ray shows that the periapical radiolucency is unchanged in size. I am telling him that no signs of healing are yet visible but that is too early to diagnose it as a “failure”. I suggest further follow-up with a new X-ray for another year. Unlike Kristina, John has a lot of questions. “How come that healing has not occurred yet? Are there bacteria left in the tooth than? Isn’t dangerous? Perhaps you should have taken my tooth out already from the beginning? Will I have pain now? What will you suggest if you don’t see healing at next check-up either? Will I have to go through any further treatments?” he asks. “I have many friends who also had root canal treatments and they never said that it took so long to heal. I’ll probably ask them. Then I will go on the Internet and search as many sites as I can about this. My feeling is that something is wrong and I need more information”.
It is striking how two patients facing similar situations took two very different approaches to gathering and processing information. Miller [53
] has categorized these two approaches to information seeking under threat as “blunters” and “monitors”. The blunter—Kristina—wants just the basics, while the monitor—John—craves more information. High monitors and low blunters chose to seek out information about its nature and onset, whereas low monitors and high blunters chose to distract themselves. Each style has its strengths and weaknesses. But, under unfavourable conditions, both styles risk becoming more flawed and hamper a good patient-dentist relation.
Only gold members can continue reading. Log In