Suboxone and Tooth Decay

Originally posted 10/21/2012
I have received a several emails over the past few years from people who experienced deteriorating dental health while taking buprenorphine or Suboxone.  I also have patients in my practice who have had extensive dental work, and wonder if Suboxone is to blame for their cavities or other problems.
I wrote about this issue several years ago.  At that time I wrote that there was no evidence that sublingual buprenorphine or Suboxone cause or accelerate tooth decay.  After writing the article I received a number of angry emails from people who insisted that I was wrong.
Let’s step back for a moment to highlight the difference between thinking something vs. proving something.  Some people misunderstood my comments about tooth decay and Suboxone, thinking that I was arguing that Suboxone does not harm teeth.  That was not what I wrote.  My point was that as of that time, there was no evidence that Suboxone or buprenorphine caused tooth decay.  When I write about the science of buprenorphine, I try my best to distinguish between what I think is true vs. what was established through scientific study.
I recently met with a patient who has had extensive dental work over the past few years, the same time that she was taking sublingual buprenorphine.  She asked if I thought that the two were related.   I made a few comments (that I’ll be getting to), but also promised her that I would do a literature search, to see whether any connection has since been established.  Ironically, a case report of a woman on Suboxone who required extensive dental work was just published yesterday.  The case report is in the latest issue of The American Journal on Addictions, and the same case is cited in the October 20, 2012 edition of Reactions Weekly.
The world of science is not efficient.  Knowledge moves forward slowly, based on findings amassed from many studies, often repeated multiple times.  Case reports are not intended to prove something.  In fact, case reports are often unusual clinical examples that defy the norm.  They are often published to point out an area that deserves more study.
I cannot copy the case report here because of copyright laws.  But the case described a 35-y-o woman who used oxycodone for about a year at doses up to 160 mg per day, and then went on buprenorphine/naloxone.  After 18 months, her dentist told her that she had extensive decay of 4 molars requiring root canal.  She reportedly had minimal history of dental problems before starting opioids or buprenorphine.
The author of the case report hypothesized that if there is a connection between Suboxone and tooth decay, one reason could be xerostomia, i.e. dry mouth, caused by buprenorphine.  The lack of saliva was my thought, too, as a mediator of any possible effects of buprenorphine on teeth.  Saliva serves an important role in dental health, including rinsing away food particles and acting as a buffer.  The patient in the case report did not report a dry mouth, so the author pointed out that all opioids have some ability to suppress the immune response, and perhaps buprenorphine and/or naloxone reduce the immune response, allowing for greater destruction of teeth by bacteria.
The case report, surprisingly, did not say which buprenorphine product(s) the patient had used, e.g. tablets, film, or generic buprenorphine.
What needs to happen next is for someone to do a case-control study of patients on buprenorphine, to see if they are more or less likely to have tooth decay.  The most valuable study is usually a prospective, randomized clinical trial;  that would not be proper here, since it would not be appropriate to randomize subjects to buprenorphine vs. no buprenorphine.  But a close second would be a case controlled study, where patients on buprenorphine are matched to ‘controls’ with similar characteristics— age, sex, eating habits, income level, education, etc.– and the dental outcomes are followed forward over a number of years.  A less-costly, less-reliable study is one that looks backward, comparing patients on buprenorphine with those not on buprenorphine to see which group has a higher incidence of dental caries.
We are not much better off at this point in our knowledge of whether Suboxone or buprenorphine predispose toward tooth decay.  The case report only mirrors what I see in my practice.  But as I often tell patients, I have other patients who are not on buprenorphine or Suboxone, who have tooth problems.  I also have patients on Suboxone with great teeth.  Hopefully some ambitious PhD candidate will sort through the issue soon.