Early Class II treatment: Part 1: The wheel keeps turning. Uncertainty and the Pyramid of Denial
Early Class II treatment. The wheel keeps turning: Uncertainty and the Pyramid of Denial
This post is about early Class II treatment. I have decided to revisit this following a joint presentation that Jonathan Sandler and I did at the recent AAO congress in San Francisco.
We were asked to participate in a point/counterpoint debate on early Class II treatment. Our role was to provide a counterpoint view to Drs Steven Dugoni and HeeSoo Oh from the University of the Pacific, Arthur Dugoni School of Dentistry, San Francisco. They have recently been promoting the benefits of early orthodontic treatment and run the early treatment clinic at the School.
They started the debate by presenting the records of some selected well treated cases and the results of an unpublished retrospective study based on patient records selected from a convenience sample. They also suggested that the results of the three well-known randomised trials into early treatment were not valid because of a lack of generality and the patients were not retained between the phase 1 and phase 2 components of their treatment.
Jonathan started the counterpoint view by summarising the current state of research knowledge based on the randomised trials and systematic reviews. (I have covered this in these posts). He also discussed important clinical aspects of early treatment and emphasised that most patients cannot wear retainers for the 2 to 3 years between phase 1 and phase 2.
I then discussed several areas and I would like to outline my points in this post and a further post next week. The first of these postings is concerned with dealing with uncertainty and denial of research evidence.
Dealing with uncertainty
In an earlier post I discussed the concept that research helps to reduce the uncertainty that is inherent in all clinical decisions. Paradoxically, this uncertainty is increased by people presenting clinical information based on low quality research and personal opinion.
When we consider reducing uncertainty on early class II treatment; we have evidence from several trials and a Cochrane systematic review. As a result, there is minimal uncertainty because this evidence suggests that routine early treatment does not provide any advantage over one course of treatment provided in adolescence in terms of; avoiding treatment, reducing complexity of Phase II treatment, the need for extractions and the final result of treatment. There is greater uncertainty about the effects on trauma and I will discuss this next week.
In spite of this evidence the subject is still felt to be controversial and I am not sure why. It appears that some clinicians simply do not accept the results of these studies and this brings me to the pyramid of denial.
The pyramid of denial
We are all familiar with the pyramid of strength of evidence that can help reduce uncertainty. For completeness I have inserted this in Figure 1.
Over the years I have debated the relative value of clinical trials and retrospective investigations. In these discussions several people have raised their concerns about the results and interpretation of randomised trials. I have decided to put these criticisms into a “pyramid of denial”. This is shown in Figure 2.
The base of the pyramid is anchored by the viewpoint that “we cannot believe the results of the studies because we know better”. This argument can be easily dismissed as it is the most basic level of denial and is based solely on personal opinion.
The next two layers are concerned with the opinion that the interventions were not applied appropriately, according to a person’s clinical experience. In other words they are suggesting that the clinicians who took part in the trial were not providing treatment “correctly”. This would mean that the clinicians were acting unethically. Again I find it difficult to accept this.
The next layer is that the treatments were not “ individualised”. This means that the investigators rigidly followed the study protocol and did not take the characteristics of the individual patients into account. This is rather unfair on the investigators. In any study the patient’s care should be a priority and while the investigators need to work to a protocol they also have to adapt their treatment in the best interests of the patient. If the interests of the patient are not considered the investigators are acting unethically. Furthermore, by providing care that is individualised the external validity of the trial is strengthened.
The final level of denial is that “my patients are different”. This means that their patients are so morphologically and genetically different from those in a trial that the results do not apply! There is really very little to say about this viewpoint except that it is very unlikely.
It is important that blog posts are relatively short and I will conclude this discussion next week in part two. “Early class II treatment: Part 2 evidence-based care and disappointment”.
Emeritus Professor of Orthodontics, University of Manchester, UK.