Levels of Evidence

"That which can be destroyed by the truth should be. That which the truth nourishes should thrive."

What's the Problem?

Evidence-based dentistry is about finding and using the best available evidence from systematic research to yield desirable and predictable clinical outcomes. One would expect that treatment recommendations would generally conform with scientific literature, but what is practised in clinical dentistry differs considerably. 

I'm not concerned about the implant surgeon who believes that placing more implants will yield better clinical outcomes, I'm talking about the dentist that zaps you with x-rays in sync with insurance cycles, regardless of your personalised need. Yes, I'm calling them out - too many of those. 

Beyond Dogma and Creed

In the world of dentistry, there are superstar lecturers, different schools of thought, and volumes of contradictory literature for the modern dental practitioner; it is often difficult to evaluate what exactly is the best available evidence. Oftentimes, the evidence isn't clear one way or another. The realm of academia has always been full of professional disagreements (I recommend A Short History of Everything by Bill Bryson as a collection of stories about thought-leaders duking it out at the frontier of academia).

Paradigms change, and it is true that some practitioners adapt quicker than others. Furthermore, you have to be able to evaluate the extent of which the profit-motive influenced your treatment recommendations. 

The hierarchy of evidence is the core principal of Evidence-Based Practice, and attempts to address uncertainty about the strength and precision of research methods.


The premise is that the higher up the hierarchy the study design is positioned, the more rigorous the methodology, and the more likely it is that the study design minimises the effect of bias on the results of the study, and therefore provides stronger evidence for treatment recommendations. In most evidence hierarchies, well designed systematic reviews and meta-analyses are at the top of the pyramid, and expert opinion and anecdotal experience are at the bottom.

Dentistry is a nuanced field. More often than not, the literature will conclude that we need higher quality studies for better evidence-based practice. Treatments are highly individualised, because every case is different. However, you should still perform due diligence and ensure that your treatments are in-line with the best available evidence.

Our Promise

At DentalTips.org, we strive to deliver the highest quality of evidence available, so you can make well-informed decisions for yourself.