Is it possible (?) to prevent the development of rheumatoid arthritis by preventing dental diseases?

Sir William Osler, a physician who is considered one of the founders of modern medicine and has signed many important observations (some of which is named after him), made the determination that “Oral health is the window to the health of the body” about 100 years ago. I remember hearing or reading this statement in some way while I was a student. Although it is difficult to clearly remember my thoughts at that time today, frankly, the feeling it created in me was something like “he exaggerated the inferences he made from the limited possibilities he had”. On the other hand, some studies conducted in recent years (which will justify Sir Osler 100 years later) have found a relationship between periodontitis (PD), a chronic inflammation in which bacteria play a role in the gums and surrounding tissues, and diseases such as heart diseases, lung diseases, and diabetes. reveals. As you can imagine, what interests me is the studies examining the relationship between PD and rheumatic diseases. Indeed, recent studies suggest that PD may be a risk factor for both the onset and progression of rheumatoid arthritis (RA).
A study that provides a closer look at the relationship between RA and oral health is published in the June issue of the Journal of Rheumatology. This study essentially explores the relationship between PD and RA. However, instead of examining whether individuals participating in the study have PD or not, the researchers focused on Porphyromonas (pronounced porphyromonas) gingivalis, a bacterium that is held responsible for the development of PD, in order to make it both more objective and more countable (quantitative). They looked at the levels of antibodies (in the blood) that developed against it.
The study was conducted in North American Indians living in Canada. There are some reasons for choosing this group in particular; First of all, this population is one of the groups with the highest incidence of RA in the world, the disease usually starts at an early age, rheumatoid factor (RF) and anti-citruline peptide antibody (ACPA) positivity are frequent, and more than one RA patient in the same family can be observed. At this point, it may be necessary to clarify the ACPA a little more. This antibody is highly specific for RA, it can often be detected in the blood even years before the onset of the disease (many laboratories in our country can perform this test under the name of anti-CCP test).
There are 3 groups in the study; 1- RA patients, 2- first degree (healthy) relatives of the patients, 3- healthy individuals who are not related to the patient group. What the researchers did was to look at the blood levels of antibodies against Porphyromonas gingivalis in these three groups.
They looked and found the following:
1- The antibody levels against P.gingivalis in RA patients are higher than both the healthy relatives of the patients and the healthy individuals who are not related.
This means that; P. gingivalis (hence PD) is somewhat related to RA, but this relationship does not seem to be related to the genetic component of the disease.
2-
a- If patients and their relatives are classified as ACPA positive and non-ACPA positive, the levels of antibodies against p.gingivalis in ACPA positive relatives of the patients compared to those with ACPA negative p.gingivalis levels in ACPA negative patients. higher than that of their relatives.
b-However, when the same comparisons were made between RF positive and non-RF positive patients and their relatives, a relationship similar to that shown for ACPA could not be shown for RF.
This means that the relationship between p.gingivalis and RA is related to ACPA positivity, which has an important place in the development of RA rather than RA in general. P.gingivalis causes PD, which causes the development of ACPA, which is thought to play an important role in the development of RA, and RA develops after a while.
Some readers may think of how P.gingivalis can be ACPA positive. There are biological reasons to explain this, but I recommend looking at the original article as it goes beyond the purpose of this article. There are 2 problems that make it difficult to interpret the results of this study; Firstly, it is difficult to interpret whether there is an exact cause-and-effect relationship since the observation made is cross-sectional (that is, he only took a photograph of that moment).
As a result, perhaps one day it may be possible to completely prevent or delay the development of RA by improving oral health. In general, most physicians (perhaps patients) think that the causes and treatment of diseases that seem so complex should be complex as well. We find it hard to believe that eliminating a bacteria in the mouth, as in this example, can completely prevent the development of the disease. However, the fact that ulcer disease, which has caused surgeons to develop new surgical methods for years, is the work of a bacterium and can be treated with antibiotics, stands before our eyes in an exemplary manner.