It’s Weird But Cannabis Smokers Are More Prone to Gum Disease
In studies, even when corrected for exposure to tobacco smoke, cannabis smokers still had a higher rate of gums receding. What is going on?
Periodontal disease, or periodontitis, is an infection and inflammation in the gums that results in loss (recession) of gum tissue and bone loss, and can eventually cause teeth to fall out. Progression of the disease can be measured by probing the gums to see how deep the pockets are surrounding the teeth.
These numbers are reported in millimeters (mm) and are referred to as combined attachment loss (CAL). CAL measurements of less than 3 mm are usually considered healthy, but 4 mm and above indicate periodontitis, with higher measurements indicating a more severe disease. There are several risk factors for developing periodontal disease, and smoking of anything is one of them.
There is a large body of health data collected from a cohort study of people born in New Zealand in which over 900 patients were studied from birth through age 38. The effects of smoking cannabis on the development and progression of periodontal disease has been extensively studied in this data.
The studies performed found that there was a significant increase in the risk of developing periodontitis by age 32 among regular smoking of cannabis. These subjects had at least one tooth with a CAL of 4 mm or greater, and the studies controlled for other risk factors like plaque and tobacco usage. Periodontal disease was also more likely to progress more severely in subjects using cannabis regularly by age 38 compared to those who did not smoke.
The precise mechanism of how cannabis affects the gums is still unclear. Several studies have been performed on the effects of smoking tobacco on the gums, since tobacco use is also a significant risk factor in the development of periodontal disease. Since many of the components of tobacco smoke and cannabis smoke are similar, effects of these compounds on oral tissues are likely to be the same. For example, one hypothesis of increased gum disease is that smoke promotes a more favorable environment for harmful bacteria in the mouth. However, there are only a few studies that have examined this mechanism and the data is inconclusive.
Another related hypothesis on the contribution of smoking to periodontal disease is the modification of the host response to the bacterial infection that causes periodontitis. The anti-inflammatory response to cannabis smoke may actually be harmful in this case, as it prevents immune cells from controlling the infection of the gums.
There is also some evidence that cannabis may share in the vasoconstriction effect that nicotine also has on gum tissue. The resulting damage to blood vessels may contribute to disease progression. In addition, the reduced blood flow may also contribute to the suppression of the immune response to the bacterial growth in the gums.
The good news is that the effects of smoking, both tobacco and cannabis, on gum health are reversible. Improvements in periodontal health, or a plateau in disease progression, were seen in those who quit smoking.