Trisha E. O`Hehir, RDH
Members of the International Association of Dental Research and a subgroup - the American Association of Dental Research - met in Orlando just a couple of months ago. Over 3,500 research papers were reported. Needless to say, I was only able to attend a small fraction of the report presentations. Many of the papers simply confirmed already-published findings, but a few reported very interesting new findings.
Two dental hygienists evaluated traditional treatment concepts from a scientific point-of-view. For these two topics we now have scientific findings rather than just tradition.
Resolving questions about pacemakers
Denise Brown, RDH and currently a dental student at the University of Baltimore, reported on her research evaluating the effect of ultrasonic scalers on pacemakers. We are all aware of the warnings about using ultrasonic scalers on patients with pacemakers, but what are the consequences? Does the pacemaker actually stop? Are all pacemakers alike? Should patients with pacemakers fear for their lives while having their teeth cleaned? How many of your patients even have pacemakers? Lots of good questions. Denise found answers to many of these questions, but as a good researcher, her findings prompted even more questions.
In her background research on the topic, Denise found that pacemakers made after 1985 are shielded internally and thus protected from electromagnetic interference. People with pacemakers are given an information card to carry with them indicating the date of manufacture and other data. She also discovered various types of pacemakers: demand-type, which pulses when needed, and individualized programming. Another category has also been added, defibrillators.
Since pacemakers are quite expensive, Denise tested used pacemakers that had outlived their owners. To create a laboratory model of the human situation, each pacemaker was placed in a large container of saline solution. The pulsing sensitivity of each pacemaker was recorded when exposed to either a magnetostrictive or piezoelectric ultrasonic scaler. None of the eight pacemakers tested demonstrated any pulsing inhibition when the scaler unit or handpiece were held five centimeters from the pacemaker. If held closer and interference was produced, simply moving the handpiece or unit beyond five centimeters corrected the situation. It seems the electromagnetic field has the potential to interfere with the pulsing of demand-type pacemakers, but simply moving the unit or handpiece a short distance completely corrects the situation.
Denise concluded from her pilot study that ultrasonic use in patients with shielded cardiac pacemakers is normally without risk. However, due to advances in pacemaker specificity and individual programming, further study is warranted. Let`s hope Denise finds time in her busy schedule to report on this research for publication, so we can learn more about her project and her findings.
Complete calculus removal necessary?
In another look at tradition versus science, Dorothy Perry, RDH, PhD, from University of California, San Francisco, reported on the occurrence of periodontal abscesses following periodontal instrumentation. We are warned about the potential of an abscess following incomplete calculus removal, but instrumentation research suggests that complete calculus removal is impossible. To see what was actually happening in this area, Dr. Perry used computerized records at the dental school to identify 1,431 patients receiving instrumentation in the dental hygiene, dental, or periodontal clinics during the 1996 spring quarter. Of those patients, only three returned to the emergency clinic for treatment. Considering the dental school setting with students and clinicians of various skill levels, the probability rate of an abscess occurring after periodontal instrumentation of just two tenths of a percent is really quite low.
Back in the days when smoking was encouraged
A few other interesting findings were:
- Endodontics usually doesn`t find its way into discussions of periodontics, but an interesting study done in Norway identified the methodology needed to link bacteria from periodontal and periapical lesions. Using DNA technology, bacterial samples can be compared to see if similar, as well as the very same bacteria, are responsible for both lesions.
- An animal study confirmed what was being seen in the control groups of several clinical studies. When comparing different clinical treatments, often the control group also showed improvement. Researchers wondered if all the probing to monitor baseline and follow-up scores was actually a form of treatment. Five older beagle dogs with periodontitis were monitored over a period of 12 months. Periodontal probing and subgingival microbial sampling at three-month intervals resulted in reduced endotoxin levels. The reductions were not enough to stop disease progress, but this may explain reduced attachment loss reported in other studies. Disruption of sensitive subgingival bacteria occurs with probing and bacterial sampling.
- In background information on smoking research, it was the Public Health Department which first encouraged cigarette smoking. It seems tuberculosis was a problem at that time and the use of spit tobacco was linked to transmission of the disease. Therefore, cigarette smoking was encouraged in order to reduce the spread of tuberculosis!
As with most meetings of this size, the best part was getting to know other participants from around the world. It is interesting to find out how dental hygiene, periodontics, and prevention fit into the picture of other countries. Discussing research projects and their findings points out the similarities as well as the differences between countries.
While the focus in North America and many European countries is on high-tech periodontal diagnostics and complex surgical treatments, other countries, often due to the lack of funding, are dealing with practical approaches to prevention and treatment for the greatest majority of people.
International meetings of this kind provide an opportunity to see the whole picture, which is made up of many points-of-view.
Trisha E. O`Hehir, RDH, is a senior consulting editor of RDH. She also is editor of Perio Reports, a newsletter for dental professionals that addresses periodontics.
