By Emma Yasinski
Stained teeth, gum disease, COPD, emphysema, and even oral cancer: Dentists already have plenty of reasons to warn patients against smoking. Now they have one more, based on a recent study in the Journal of Endodontics showing that patients who smoke cigarettes have lower concentrations of important immunological cytokines in their dental pulp – limiting their ability to fight disease and heal.
Smokers tend to have worse endodontic outcomes than non-smokers. Most dentists already know that smoking is associated with delayed healing and more frequent endodontic lesions. But there has been little research on how smoking impacts the inside of the teeth – the pulp – which houses cells that form reparative dentin.
The new study may explain the difference in outcomes.
“This is the first observational clinical study to explore the interaction of some of the inflammatory cytokines in the smokers and non-smokers,” Anita Aminoshariae, DDS, MS, associate professor of endodontics and director of predoctoral endodontics at the Case Western Reserve University School of Dental Medicine told Incisor.
Dr. Aminoshariae and her team conducted an observational study on 32 smokers and 37 non-smokers. The patients were separated into groups based on whether they had normal dental pulp, symptomatic irreversible pulpitis, or asymptomatic irreversible pulpitis.
She and her team suspected that smoking would decrease the ability of the pulp to defend against pathogens. The scientists examined the pulp of each patient and measured the levels of several immunological cytokines, TNF-α, hBD-2, IL-1β, and hBD-3.
While all the patients had similar levels of IL-1β and hBD-3, smokers had significantly lower levels of TNF-α and hBD-2. However, the difference could not be explained by the state of the patient’s pulpitis.
"That might explain why smokers have poorer endodontic outcomes and delayed healing than non-smokers," said Dr. Aminoshariae, in a press release. "Imagine TNF-α and hBD-2 are among the soldiers in a last line of defense fortifying a castle. Smoking kills these soldiers before they even have a chance at mounting a solid defense."
On the bright side, one patient who had quit smoking just two weeks before his samples were collected, had cytokine levels similar to the non-smokers. “This might suggest that the process is reversible and not permanent,” said Dr. Aminoshariae.
However, this study was only observational, and there are still several questions that need to be answered.
First, since the patients in this study self-reported their smoking, a more accurate measure would be to measure cotinine, the principal metabolite of nicotine and compare it with cytokine expression. Another future study should compare cytokine and immunoregulatory expression in the dental pulp with that of blood in the oral cavity and throughout the body.
Lastly, long-term outcome studies of non-surgical root canal treatment will be important to determine the impact of delayed healing.
Author: Contributing writer Emma Yasinski received her Master of Science (MS) in science and medical journalism from Boston University. Her articles have also appeared at TheAtlantic.com, Kaiser Health News, NPR Shots, and Genetic Engineering and Biotechnology News.
Other Recent Incisor Articles by Emma Yasinski:
- Using Ketamine as an ‘Alternative’ to Opioids Requires More Caution Than Previously Recognized
- Would You Like Some Cream and Sugar with Your Novocain?
- This Research Holds Great Promise for Dental Enamel Regeneration
- Despite Some Improvement, Seniors Still Struggle with Oral Health - Report
- Would Your Patients Agree to Be Treated By a Robot for 50% Off Normal Fees?
- A Recent Study Found That More Than 30% of the Opioids Used by Children Were Prescribed by Dentists