Gums, Germs and Gestation
by Jacquelyn Spruce
Flossing, fluoride and frequent visits to the dentist should not be "brushed off" during pregnancy. In fact, avoiding these three things could cause severe medical complications for the baby. What do gum disease and preterm births have in common? The answer may have many mothers-to-be reaching for their toothbrushes.
The Health Science Center is one of three national sites conducting a five-year study examining the correlation between periodontal (gum) disease and preterm births. The MOTOR trial - Maternal Oral Therapy to Reduce Obstetric Risk trial - will observe 1,800 pregnant women nationwide with periodontal disease and examine the effects it has on their birth outcomes.
Health Science Center researchers
David Cochran, D.D.S., Ph.D., chairman of periodontics, and Donald Dudley, M.D., professor of obstetrics and gynecology, are co-principal investigators for the San Antonio site of the MOTOR trial. Six hundred San Antonio women will participate in the study - now in its third year - which offers dental procedures that treat periodontal disease. Approximately 100 women are currently enrolled.
Drs. Dudley, Cochran and other researchers in the MOTOR trial are not permitted to see the results of the study until it is at least halfway complete. While they continue to focus on the correlation between preterm birth and periodontal disease, the answer is believed to lie in the body’s ability to fight bacteria.
"Both periodontal disease and preterm birth appear to be the result of an overly active inflammatory process," Dr. Dudley said. "Inflammation is a response by a host - in this case a person - to an infection. Some inflammation is necessary to control infection. Too much inflammation is harmful, as it harms the host."
A variety of bacteria live in every mouth, Dr. Cochran explained. When the body cannot fight the bacteria, periodontal disease results.
"For years researchers thought the cause of periodontal disease was the bacteria on the teeth," Dr. Cochran said. "We now realize that the disease is caused by our own host response to the bacteria. So the bacteria are necessary, but not sufficient, to cause periodontal disease. Each body will respond differently."
"Approximately 12 percent of all pregnancies in the United States are delivered before term," Dr. Dudley said. "Since 1980, the rate of preterm birth in the United States has increased by 50 percent. Several studies have been conducted, but nothing has decreased the preterm birth rate in this country."
Preterm births are more likely to result in serious medical conditions for the child, including intraventricular hemorrhage (bleeding of the brain), cerebral palsy, retardation or at worst, death.
"Changing even 1 percent of the preterm birth rate in this country would be incredible because a child’s life has been influenced - not just at birth, but throughout the child’s entire life span," Dr. Cochran said. "It’s really significant that we might be able to do this simply by cleaning the mother’s teeth."
Drs. Dudley and Cochran hope that the results of the MOTOR trial will prove their hypothesis to be true.
"In order to prove the association, we have to conduct a large interventional clinical trial that shows a cause and effect. That is why the length of the study and the large amount of individuals involved are so relevant," Dr. Cochran said. The University of Alabama and the University of North Carolina at Chapel Hill/Duke University are the two other sites involved in the trial.
All participants receive basic obstetric and periodontal exams when they enter the study. The women are then randomized into two groups. One group is treated for periodontal disease with non-surgical procedures called scaling and root planing. They are treated by or no later than the first 24 weeks of pregnancy. The other group is treated post delivery, and all women receive an additional periodontal exam after they deliver.
The MOTOR trial is ethnically balanced to ensure it is applicable and generalized to the U.S. population.
"We recruit women early in their pregnancy," Dr. Dudley said. "The majority of the women in the San Antonio MOTOR trial are Hispanic. The other sites tend to recruit women who are non-Hispanic white or African-American. It’s necessary to look at individuals from all ethnic backgrounds to have a complete study."
All participants receive an immediate periodontal exam post delivery. Therefore it’s essential that the researchers are notified when the women deliver. All participants are required to give birth at the same hospital to ensure immediate post-delivery attention from the researchers.
Although the link between periodontal disease and preterm births has not been established, studies of periodontal disease have shown it to be a high-risk factor of many diseases, including diabetes, cardiovascular disease and obesity.
So what is the best way to avoid gum disease? "The more you clean your teeth, the better off you and your children will be," Dr. Cochran said.
What is periodontal disease?
Periodontal disease occurs when bacteria in the mouth are not eliminated by the body. When left untreated, bacteria cause bone and tissue damage that can lead to tooth loss.
• Gums that bleed easily
• Red, swollen or tender gums
• Gums that have pulled away from the teeth
• Persistent bad breath
• Pus between the teeth and gums
• Loose or separating teeth
• A change in the way teeth fit together when biting
• A change in the fit of partial dentures
Source: American Academy of Periodontology