Tobacco smoking is known to increase the risk of periodontal disease. Now, a study says that young adults who regularly smoke marijuana also may be at risk for the disease.
Researchers from the Dunedin School of Medicine in Dunedin, New Zealand, studied 903 people. They answered questions about their habits and health at age 18, and again when they were 21, 26 and 32. Researchers also examined their mouths at ages 26 and 32.
People were divided into three groups:
- Those who never smoked marijuana (32%)
- Those who smoked it 40 times or fewer each year (47%)
- Those who smoked it more than 40 times each year (20%)
At age 32, about 29% of the people in the study had moderate periodontal disease. Another 12% had serious periodontal disease.
Gum health got worse between ages 26 and 32 for about 24% of the people who smoked the most marijuana. In the low-use group, 11% had a decline in gum health during this time. In the no-smoking group, 7% did.
It could be that frequent marijuana users also don't take good care of their teeth. That may be part of the reason they have more gum disease. To account for that, "We controlled for their use of dental services over the previous six years, and we controlled for how clean their teeth were," said W. Murray Thomson, Ph.D. Murray is a professor of dental epidemiology and public health at Dunedin School of Medicine. He is first author on the study.
The researchers also took tobacco smoking into account. The researchers also accounted for social and economic status and gender. All of these factors affect the risk of periodontal disease.
Compared with people who never smoked marijuana, people who smoked the most marijuana:
- Were 60% more likely to have moderate periodontal disease
- Were 3 times as likely to have serious periodontal disease
- Were 2 times as likely to have gum health get worse between ages 26 and 32
People who smoked marijuana less often (1-40 times per year) also were at increased risk of periodontal disease. They were about 35% more likely to have moderate disease than non-users. They were 2.5 times as likely to have serious disease.
The authors say that long-term marijuana smoking can affect gum health.
Periodontal disease causes the gums to pull away from the teeth. At its worst, periodontal disease can cause teeth to fall out.
The research appears in the February 5 issue of the Journal of the American Medical Association.