- Dr. David Alfaro
The Sonicare vs Oral B Battle.
Apparently my last post had some photographs on it that grossed people out. Sorry about that….this one will be full of cute furry things.
But seriously, gum disease like what was on that last post is what I see every day in my office, and it is mostly avoidable. Hopefully the offensive nature of the physical outcomes of gum disease will get some of you brushing and flossing better.
Continuing on from before, I said that we were going to look at the Sonicare vs Oral B battle….well to properly do that, we have to look at how we research this kind of stuff in dentistry. Warning.....this is really nerdy.
Let us talk plaque control (totally gonna be trending after this).
How do we know that plaque and calculus cause gum inflammation?
Believe it or not, one of the “classic” papers on this topic was a university study where the researchers got a group of students to stop brushing their teeth and followed what happened. Pretty gross, but people did volunteer for the project. This study, and many others since then, showed that if one stops brushing, plaque and calculus accumulate, and if plaque and calculus accumulate, the gums get inflamed.
It is pretty easy to make that connection between plaque and inflammation, but measuring the effect is a different story. In order to do so we need to evaluate how much plaque causes how much inflammation, meaning we need to be able to quantify plaque, and to quantify inflammation. That is just plain arbitrary with our current measurement techniques (sorry plaque researchers).
Measuring plaque is not like timing a race, or measuring how high someone can jump. Those things can be measured in time or distance, which is good because they are continuous values that we can compare with basic statistics. Huuuhhh??? Well….. if someone runs a race in 10 seconds, and another person takes 20 seconds, it is easy to say that one person was twice as fast.
For plaque and inflammation, however, we do not have linear, continuous ways of measuring. Even if we scraped all of the plaque off of someone’s teeth and tried to measure it by weight, there would be too many errors to make proper conclusions. The way that most researchers evaluate plaque and inflammation are with “indexes” that are descriptive in nature.
Plaque index, for example, evaluates the amount of plaque by arbitrarily splitting things into various groups where 0=no plaque 1=a little 2=more, etc etc etc….. These values, since they are not on a continuous scale (like time or distance), should not have basic averages and differences applied to them. Confusing????
Say someone is really good looking and we call that value a "1", and someone else is really, really, really good looking, and we call that value a "2". We cannot take the average of those two numbers, because the “2” category isn’t necessarily two times as good looking as category “1”. Unfortunately, we see this all of the time in plaque research, where the data is presented in this manner...."the average was 1.5".....which is incorrect.
“what is this? a centre for ants???”
For inflammation, we do not even measure it directly; we use something that we assume is correlated to it, like pocket depth, or bleeding on probing. The challenge with this is that there is a lot of measurement error. How hard do you poke the gums? What angle do you poke at? What locations? How wide is the probe? How much bleeding is there? All these variables add up to large measurement errors. We are not measuring a race with a stopwatch.
When we look at probing depths, for example, the net result of those measurement errors is that realistically, we do not know if there is a difference between a 2 or 3 mm pocket, because, well we may have just measured wrong. It is easier to conclude that there is a difference between a 6-7 mm pocket and a 2-3 mm pocket, but not between 6 and 7 mm or 2 and 3 mm pockets.
The good thing is that there is a clinical difference between the two. We may not see a big difference within someone who has a lot of 2 or 3 mm pockets; things will be generally healthy. We will also not see much difference in areas with 6 or 7 mm pockets……they are gonna be bleeding, swollen and sore, especially in comparison to someone with 2-3 mm pockets.
How does this affect how we interperet dental research on toothbrushing?
The amount of measurment error in our current techniques makes me very skeptical of any research that is published on specific toothbrushes or toothpastes. Yes, we know that plaque control is paramount. We know that if people do not brush, plaque accumulates and gum inflammation happens. But most toothbrush research is performed on people who have gingivitis, but not periodontitis, because toothbrushing alone is not going to improve a deep pocket that people with periodontitis would have.
That means that most toothbrush research is performed on people with 2-3 mm pockets. Hypothetically if an article states that a specific toothbrush improves the pocket depth 10%, say from 3 to 2.7……it may mean that statistically one is better, but does it matter in the real world? No, clinically 2.7 and 3 are the same, and realistically, we do not have measurument techniques accurate or precise enough to reliably distinguish between 2.7 and 3.
What does it meaaaaannn???
Double rainbow all the wayyyyyyyy......
Humans are generally bad at toothbrushing; they simply don't enough, and when they do, they are not efficient at removing biofilm. If we look at research where plaque is measured before and after manual toothbrushing, we suck. There is always plaque left, even with the horrible measurement techniques we have in dental research.
When electric toothbrushes are compared to manual brushing, the improvements in plaque control with a powered toothbrush are significant enough that they may cause a clinical improvement.
There is not enough (and there probably will never be enough) research to prove that one powered toothbrush is better than another. The evidence as it stands tends to slightly favour the Oral B but there are many articles that support the Sonicare. Regardless of the outcome, the statistical difference between brands of toothbrushes is so little that clinically they have same effects.
For me, the winner is the one that people will actually use. Definitely use a powered toothbrush, daily. It is more expensive, but they do work for you, they are gentler on the roots of the teeth, and keep you to a timed regimen which keeps you consistent. Yes, an electric toothbrush is expensive, but if it improves your habits, they are a good investment, because believe me, dealing with gum disease and caries is much more expensive than a 5-pack of replacement heads for your Sonicare.
Thanks for reading!
Dr. Dave
drdave@alfaropros.com
