What information can we give to our patients about the evidence on orthodontic care?
The more observant readers of this blog will have noticed that I have not posted for a few weeks. This is because I have been away in Australia lecturing and taking a holiday. This is why I have illustrated this post with a picture from my trip down the Great Ocean Road. I was a speaker at the excellent Australian Royal College of Dental Surgeons conference in Hobart and I gave three presentations. One of these was on the information that we can give on the evidence on orthodontic care. I have posted about this before but I would like to make this new post a short precise of my presentation and update my previous posts with a particular emphasis on the process of informing our patients as part of the consent process.
Uncertainty and clinical decisions
All aspects of our lives are influenced by uncertainty and this is particularly true for the clinical decisions that we take. It is clear that there is no such thing as 100% certainty in clinical decisions and the aim of scientific investigation is to try to reduce this as much as possible. Unfortunately, clinical uncertainty is increased by claims for treatments that are not based upon research evidence. Evidence based orthodontics When we consider the nature of evidence that should reduce uncertainty a good place to start is the well-established pyramid of clinical evidence. (Figure 1).
This ranks the type of research study design in terms of the strength of the evidence that it provides.
While this emphasis is commendable, we should not forget that the optimum practice of evidence-based care is not solely influenced by research. For example, Sackett pointed out that we should consider that there are three components that contribute to evidence based care, these are: clinical research, clinical experience, and patient opinion. (Figure 2).
The proportion of each component that influences a final clinical decision is influenced by their relative strengths. For example, if research evidence is available then this should play a greater role than clinical experience. Importantly, all evidence that is based on clinical experience and research should be fully explained to our patients in order that they can make the choice on their treatment.
Paradoxically, there is also a resistance to accepting the results of clinical research I have been challenged in discussions on the interpretation of my research and I have put these arguments together as a “pyramid of denial”. This is shown in Figure 3.
These arguments should be avoided.
How can we practically provide information to our patients when we are uncertain?
I would like to illustrate this with information that can be identified from two Cochrane systematic reviews. This first is our recently completed systematic review into orthodontic treatment for prominent teeth. In this review we aimed to assess the effect of early orthodontic treatment for class II malocclusion. We identified three large randomised trials, which are well known in orthodontic research. For most of the orthodontic effects of treatment there was no advantage of treating children early. Nevertheless there was some evidence that this resulted in a 9% reduction in the incidence of trauma. While this finding may be clinically important there was a moderate degree of uncertainty in these findings. This means that when we discuss this issue with our patients, we need to discuss our clinical experience and the risk to our individual patients, in addition to the research evidence. For example, we may consider that an 8 year old boy with a 14mm overjet who loves skateboarding is at considerable risk of trauma and should be treated early.
When we look at the review by Simon Littlewood and team on retention, the evidence is not so clear. For example, they found very little difference between differing retention regimes and relapse and patients preferred vacuum formed retainers to Hawley retainers. They pointed out that most of the studies were at high risk of bias. As a result, we must consider that the amount of uncertainty on retention is high and clinical experience and patient preferences take a greater role in the decision on retention. When I reviewed this paper I stated that my preference is to use vacuum formed retainers, as patients prefer them and my clinical experience of the long term wear of bonded retainers for the average UK teenager is not good because of a high incidence of breakage and unwanted tooth movement. As a result, we can conclude that when we discuss treatment with our patients we can be moderately certain on our recommendations on early orthodontic treatment but less certain on deciding methods of retention.
Evidence and consent
The provision of evidence-based care clearly has an important role in providing information to operations as part of informed consent. In the United Kingdom this is clearly set out by the professional regulator, the General Dental Council. The issue of consent in the UK has recently changed following a recent court ruling. The judgement is rather complicated but may be summarised by considering that the relationship between the doctor/dentist should should be a partnership based on trust and openness. This means that our patient should be well-informed about significant risks and reasonable alternative treatments. We, therefore, need to be able to provide more information to our patients about the risks and benefits of orthodontic care. This leads us to the difficult question “is some of our evidence good enough”? There are certainly some areas where we have good information, for example, the effects of functional appliances, whether early treatment for some conditions is effective, the relative performance of self-ligating and conventional brackets and the use of TADS. But in other areas, for example, methods of retention and the effects of orthodontic treatment on dental health the evidence is not so clear. I have no doubt that we need to carry out more meaningful research so that we can fully inform our patients as part of the consent process.