by Lynne H. Slim, RDH, BSDH, MSDH
On the spur of the moment in early August, I scheduled a flight to Los Angeles to attend an anti-infective therapy course with Jorgen Slots, a world-renowned professor of dentistry and microbiology at the University of Southern California School of Dentistry. Dr. Slots completed his postgraduate degree in periodontology in Copenhagen, Denmark, and obtained a certificate in microbiology from the Forsyth Institute in Boston.
When there is any opportunity to hear a prominent periodontal researcher talk about my favorite subject, I seize it with wild and enthusiastic abandon, and this experience was typical. I was also excited about spending a couple of days with my trusted friend, Noel Kelsch, RDH, who lives in Moorpark (north of Los Angeles near Simi Valley).
I’ve never met Dr. Slots in person but I have talked to him by phone a couple of times. He has a Danish accent and his laugh is unforgettable and very distinctive.
As I sipped my morning coffee while sitting in the audience, I looked around the room and noticed many foreign students and practitioners, and I was eager to talk to many of them.
I’m like a kid with both hands in a candy jar when I attend a good periodontal course, and this course was no exception. I already knew that Dr. Slots is editor-in-chief of three leading dental journals: Oral Microbiology and Immunology, Periodontology 2000 and the Journal of Periodontal Research. He has published and lectured extensively in periodontology, implantology, microbiology, immunology and molecular biology.
Dr. Slots began the course with a review of anti-infective approaches to dental caries and periodontal diseases from the early 1900s to present day. I knew that I would like his lecture format, which was very informal with lots of opportunities to ask questions during the day-long presentation. Since I am an Energizer Bunny when it comes to reading periodontal literature, Dr. Slots wanted to know who I was after my hand kept shooting up in the air with question after question. I recall joking with him that he “wouldn’t want to know” and then later I did tell him of my affiliation with RDH magazine and PennWell Corporation.
It’s impossible to cover all of the topics that were presented in this course so I’ve decided to limit discussion to one topic in particular - household bleach and other antimicrobial agents. It was back in 2003 that I first became interested in Dr. Slots’ views on the selection of antimicrobial agents after reading an article he authored on this topic in the Journal of Periodontal Research.1
Dr. Slots enjoyed reminding the audience that sodium hypochlorite has been used as a disinfectant for more than 100 years and that the American Dental Association (ADA) once approved it in diluted form as a mouthwash. He indicated in his lecture that this particular disinfectant (when diluted in the ratio of one part sodium hypochlorite to 20 parts water) has many of the properties of an ideal topical antimicrobial agent but that its recommendation to patients has become an “emotional” issue. In comparing sodium hypochlorite to hydrogen peroxide, he mentioned that bleach has substantivity and penetrates biofilms.
Dr. Slots is not in favor of using chlorhexidine gluconate as an oral irrigant or mouthwash because of the extrinsic staining that is associated with its use. In singing the praises of sodium hypochlorite, Dr. Slots pointed out to the audience that endodontists now use only bleach whereas they used to use hydrogen peroxide in root canal irrigation.
Hygiene and Anti-infective Therapy
My ears perked up when Dr. Slots talked about dental hygienists being serious players in the world of anti-infective therapy. My hopes were dashed later on in the day when he continued to elaborate on our role in dental practices, but I came away with a much better understanding of future considerations for us as oral wellness experts.
Before we proceed with a discussion of Dr. Slots’ lengthy denunciation of other topical anti-microbial agents in favor of bleach, I’d like to talk to you about our appetizing “before lunch” experience.
As part of clinical participation, course participants were invited to experience an instantaneous benefit of sodium hypochlorite as a mouthwash when it is diluted with water at 1 part sodium hypochlorite to 20 parts water. As we wandered down the hall to USC’s dental clinic, I worried about what was going to take place. The thought of rinsing for 30 seconds with diluted bleach is fairly repulsive to me.
Sure enough, I was handed a plastic cup with the concoction and I was thoroughly sickened by the taste of the bleach solution and my tongue felt as though it was on fire too! The course participants I talked to felt the same way, and many of us lost our appetite for lunch and had trouble chewing food after the bleach-rinsing exercise!
Even though there is weak evidence to support the use of sodium hypochlorite as a useful home irrigant or mouthwash if diluted according to Dr. Slots’ recommendations, it’s a “purely academic” exercise to recommend it to patients - most of them won’t partake! When I have a patient whose periodontium is inflamed despite everything else I’ve tried, I have recommended home irrigation with a sodium hypochlorite solution. The patient’s response is the same most of the time: “I’m interested in something to add to the bath water that might be less toxic.”
Sometimes I believe that academic researchers live in a different world than the one I live and work in!
Dr. Slots has opinions on just about everything periodontal. Much of what he has to say is backed by sound science and years of study and contemplation. For example, he feels (quite strongly, I might add) that non-steroidal anti-inflammatory agents to control inflammation in periodontal patients are totally worthless. He believes that inflammation is our friend. I, on the other hand, disagree, based on what I’ve read and studied about the hyper-inflammatory response theory. It’s too premature to know who is correct and who is incorrect. Like Dr. Slots, however, I’ve often wondered if low dose doxycycline administered twice a day merely masks inflammation.
When a leading periodontal researcher like Jorgen Slots tells me that he has “zero” failures in treating periodontal patients, I stand up and take notice. In writing this particular column, I can’t discuss in detail all of the topics that Dr. Slots covered but I can highlight some important points and I want to begin with a real humdinger.
Humdinger Of A Point Worth Remembering
Shortly after we returned from lunch (remember that mine was flavored with bleach ... not exactly an ideal taste!), Dr. Slots struck a nerve with me when he casually mentioned that dental hygienists would have to find something else to do in the dental practice when patients present for a two-hour SRP and there is no subgingival calculus.
Those of you who know me well also know that I do not suffer fools gladly and sometimes I tend to react impulsively rather than counting to 100 and calming down. Dr. Slots looked directly at me, and I wanted to jump out of my chair and onto the stage. I am so used to a small number of dentists trying to “put us down” or “put us in our place” as they see fit.
That’s what I thought that Dr. Slots was doing, but I was wrong. He was actually making a very good point! In the absence of subgingival calculus, what is the point in scaling for hours on end? “Scaling” is done to remove hard deposits and biofilms but it doesn’t take two hours to clean and disinfect pockets in the absence of tenacious deposits. Isn’t it more therapeutic to debride the biofilms and loosely attached endotoxins and disinfect the pocket instead? Ultimately, our microbiological goal subgingivally is the conversion of an anaerobic environment to a supragingival facultative environment that is more compatible with health.
So what do we do when a patient is scheduled for four quadrants of scaling and root planing (split mouth, two quadrants at a time)? In actuality, what the patient really needs is full-mouth debridement and disinfection.
SRP Burned In Effigy
For starters, the term “scaling and root planing” is an outdated one that needs to die and be burned in effigy. The term conjures up thoughts of hand scaling for hours on end with curettes and sickles, and we all know that we’ve moved way beyond hand intrumentation into the wonderful, more ergonomic world of ultrasonics. It’s bad enough that we are still working blind (and my hope is that someday we will have affordable periodontal endoscopes to accompany our ultrasonic instrumentation).
Dr. Slots mentioned in his lecture that he once heard someone state that dental hygienists should be educated to a level that only God could accomplish. I was ready to jump out of my seat at this comment too. But he completed his thought by saying that it would be impossible for us to have impeccable instrumentation skills because we are working blind in periodontal pockets. Again, I agree with his point of view.
It is simply ridiculous to emphasize that scaling and root planing on its own constitutes anti-infective therapy. Dr. Slots raised his voice and yelled out, “Scaling and root planing, hallelulah!” I knew that he was making yet another important point. Scaling and root planing as an end-all-be-all procedure makes no sense. Dr. Slots recommends using povidone-iodine as a pocket disenfectant to accompany SRP, because he says that it kills 98 percent of bacteria. For subgingival irrigation, an effective concentration in an endodontic syringe is 10 percent, applied repeatedly for at least five minutes. In ultrasonic scalers, 10 percent povidone iodine is diluted by mixing 1 part solution with 10 parts water.
As the afternoon wore on, I decided to stretch my legs and slip outside for a cup of coffee. Just as I was about to make a mad dash from the lecture room, Dr. Slots issued another hygiene-truism: If I were a dental hygienist today and I had a patient with no calculus but a periodontal infection, I would do a fast and sloppy scaling with povidone iodine and then have the patient rinse with an appropriate bleach solution at home. “OK, Dr. Slots,” I mumbled to myself, “I’ll go along with disinfecting to enhance debridement of biofilms but the bleach recommendation is one that I’ll have to pass on for now.”
Dr. Slots has a bit of a cult following in some dental circles, particularly with his household bleach recommendations. He states that several Los Angeles celebrities walk around swilling a 1:20 bleach solution for 30 seconds twice a week and being treated nonsurgically at the USC School of Dentistry, Los Angeles. To this, I say, “I love and respect you, Dr. Slots, but let’s please leave plain household bleach in swimming pools or washing machines where it belongs.”
1 Slots J. Selection of antimicrobial agents in periodontal therapy. J Periodont Res 2002; 37; 389-398.
About the Author
Lynne H. Slim, RDH, BSDH, MSDH, is a practicing hygienist/periodontal therapist who has more than 20 years’ experience in both clinical and educational settings. She is also president of Perio C Dent Inc. (Perio-Centered Dentistry), a practice-management consulting firm that specializes in creating outstanding dental hygiene teams. Lynne is a member of the Speaking and Consulting Network (SCN) that was founded by Linda Miles, and has won two first-place journalism awards from ADHA. Lynne is also owner/moderator of a periodontal therapist yahoo group: http://yahoogroups.com/group/periotherapist. She can be contacted at firstname.lastname@example.org.