Th 220104

Evidence vs. spin

Aug. 1, 2006
Every week in clinical practice, I meet at least one patient who entertains me with a fascinating story.

Every week in clinical practice, I meet at least one patient who entertains me with a fascinating story. This past week was no exception. A 30-something female patient entered my operatory and I noticed almost immediately that she had a very pretty face. After reviewing her health history, I placed her recent fmx on the viewbox and saw on the radiographs - to my surprise - some interosseous wires in the maxilla. I questioned her about them. Here’s the incredible story that spilled forth ...

About a year ago, my female patient (we’ll call her Nancy) and her husband were driving on a New Hampshire highway at high speed late at night. Nancy was sleeping in the passenger’s seat and her seat was fully reclined. An 800-pound moose ran out in front of the car and struck it. Apparently, the legs of the beast went under the car and the entire carcass, minus legs and hooves, flew up into the air and landed on the roof of the car. The roof caved in and hit Nancy in the face. Parts of her maxilla and zygomatic bones were broken in several areas. Nancy was transferred by ambulance to the Dartmouth-Hitchcock Medical Center. In studying Nancy’s face from the outside, I would never have known that anything had ever happened to her. Nancy credits her amazing surgical results to her physicians whom she described as “the best of the best.”

As my day progressed, I had fun relaying Nancy’s story about the poor moose, but I also began to think about the topic of excellence in health care and what separates the best health-care providers from the average or even poor.

I thought long and hard about today’s world of complex decision-making and tried to make sense out of all the data that comes our way. We are bombarded by monthly magazines and journals, continuing-education courses, chat groups, ads, salespeople, and “spin doctors” who are able to put just the right slant on a product to make it sell. We all know that some of the most visible public speakers are well compensated or “sponsored” to promote the sponsoring company’s products, and pharmaceutical reps are schooled for weeks on end in a variety of sales techniques so that they can effectively “spin” volumes of data about their products. We all enjoy the free lunches, the gifts (such as pens and Frisbees), and the occasional surprise packages that arrive in the mail. If Hygienist No. 1 is treated to lots of free samples to encourage him/her to sell a product, or if the hygienist convinces the dentist that he/she works with to prescribe a certain product, the pharmaceutical company’s weekly prescriber reports will show the company just how effective a particular salesperson has been in that particular month.

So we need to ask ourselves: what can be wrong with that approach to drug or other product sales? Is it OK to invite a favorite sales rep in for a lunch-and-learn? You betcha - as long as you understand your responsibility to the patients you serve and you put their needs and preferences first. I love my sales reps; some of them are my best friends. Here’s an example of what you might want to do in a particular situation. A salesperson comes along for a lunch-and-learn and tries really hard to convince you that his/her company’s power brush is superior to another one on the market. The salesperson presents you with lots of colorful graphs and plugs clinical research that touts the advantages of this power brush over a competitor’s. The next morning, Mrs. Jones enters your operatory. There on the display table right in front of Mrs. Jones is a nice display of one particular power brush and it happens to be the one that was being promoted during yesterday’s luncheon. Mrs. Jones asks you a question: “I’ve been thinking about buying an electric toothbrush, and I’m counting on you to tell me which one is rated the best.”

How do you answer this question in a way that lets your patient know that you are not making a sales pitch but that you really do know the research behind power brushes? Do you spit out the same information the salesperson gave you yesterday or, instead, have you done your homework and researched the literature, searching for an unbiased answer that is supported by several reputable research studies?

It may sound easy to review the literature and make a determination that

way, but sometimes even the experts can’t agree on which product or procedure is best! For starters, finding the best available research evidence is an exhausting process. Sometimes the information doesn’t even exist. A mathematical mind is required to analyze the data (if it hasn’t yet been done), and research studies need to be based on randomized clinical trials that cost millions of dollars and take years to accomplish. A special computer analysis or “meta-analysis” is needed to evaluate all of the data in the clinical trials and then a “systematic review” has to be written, which details the findings and makes recommendations based on the extensive data analysis. In addition, evidence-based decision-making must include clinical expertise (yours and others in the know) and client preferences. What a complicated exercise!

The “evidence-based movement” exists to provide extensive information to practitioners on the outcomes of treatments in order to understand the best approach to care. For example, how do we know whether or not in-office irrigation following SRP results in a positive outcome? Where do we look for that information, and does it even exist? In this particular example, there is some evidence regarding which in-office irrigants work best and whether or not in-office irrigation benefits our patients in the long run.

Here’s another important question that begs an answer: in patients with chronic periodontitis, what is the effect of local controlled-release anti-infective drug therapy with SRP compared to SRP alone? I’ll attempt to answer these two important questions based on evidence. I am a very detail-oriented person who likes to read systematic reviews on periodontal topics of interest. (My family and my four dogs still love me in spite of my quirky ways, and that’s what counts anyway!)

In the 2003 Annals of Periodontology, I devoured a systematic review that reported on the two aforementioned questions.1 Unfortunately, in attempting to answer the question about in-office irrigation, I found that only irrigation with chlorhexidine was included in the review. Povidone iodine, another popular in-office irrigant, was not included in the meta-analysis. It is possible that it didn’t meet the criteria, meaning that there aren’t enough long-term clinical trials available to analyze. Using a reduction of probing depth and bleeding on probing as outcomes, no evidence was found for an adjunctive effect of therapist-delivered chlorhexidine irrigation.

Since I am an inquisitive nitpicker who has attended many lectures by periodontal researchers and others who support the use of povidone iodine as an in-office irrigant, I carefully researched several studies and read articles written by periodontal researchers who sing the praises of povidone iodine. Here is the conclusion I came to based on the available science: povidone iodine is a powerful antibacterial agent and is useful in preventing a bacteremia before dental procedures and after surgical procedures. There is weak evidence that povidone iodine, in conjunction with SRP, provides additional gains in clinical attachment, but none of the studies is large enough to be irrefutable. Povidone iodine is inexpensive, however, and is used extensively in wound management. Consequently, I concluded that it is perhaps beneficial and safe if used in-office. Slots, a periodontal researcher at USC, recommends povidone iodine as an irrigant, and he also advocates the use of diluted bleach as an in-office irrigant.2 Keep in mind, however, that we may never have the long-term clinical trials needed to solve the uncertainties pertaining to the effectiveness of in-office adjunctive irrigants like povidone iodine and bleach.

In reading two systematic reviews on local controlled-release anti-infective drugs as adjuncts to SRP, I found that both systemic reviews were in agreement.1,3 Several local anti-infective agents - including minocycline microspheres, doxycycline gel (which is unavailable in the United States), and the chlorhexidine chip - provided additional benefits to probing depth reduction and clinical attachment gain. However, clinicians must recognize that the average probing depth reduction obtained by adding a sustained-release antimicrobial to SRP is quite small but perhaps clinically significant - particularly in areas that are inaccessible. It is important to weigh benefits and cost of the procedure, and both the therapist and the patient should make decisions about therapy together. Keep in mind that probing depth reduction and clinical attachment gain are considered “surrogate” outcomes, meaning these outcomes may have nothing whatsoever to do with long-term “real life” outcomes such as tooth retention and comfort.

Nursing is further ahead of dental hygiene in the new revolution called evidence-based health care. In nursing, funding opportunities for research are available through the National Institute for Nursing Research (NINR), and there are many new nursing journals that emphasize research. Evidence-based nursing practice has already been well-defined and implemented. Nurses learn these important steps in the research process while studying for their nursing degrees:

• Identify issues or problems that need answers.
• Search the literature and evaluate the available evidence using specific criteria regarding scientific merit of the available data.
• Choose interventions and justify their choices with the most valid evidence.

Evidence-based dental hygiene is a topic that I am particularly passionate about. I often find myself swimming against the tide of different opinions (which often have no scientific basis), and I sometimes get exhausted in this attempt to help clinicians adopt a rational approach to oral health care using the best available research evidence coupled with clinical expertise and client preferences.

Some dental hygiene clinicians may say they don’t have the time or interest to keep up with the evidence. Always remember that health-care professionals are awarded this title because we “profess” to continue our education and justify our decisions. In addition, our patients trust us to choose treatment options that are in their best interests and based on an ongoing commitment to professional values and ideals. It is not every day that we are confronted with a patient who was hit by a moose. Nonetheless, the challenges we face on a daily basis demand ethical, patient-centered, evidence-based decisions.

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1 Hanes PJ, Purvis JP. Local anti-infective therapy: pharmacological agents. A systematic review. Annals of Periodontology, 2003 workshop on contemporary science in clinical periodontics; 79-93.

2 Slots J. Selection of antimicrobial agents in periodontal therapy. Periodont Res 2002; 37:389-398.

3 Bonito et al. Impact of local adjuncts to scaling and root planing in periodontal disease therapy: a systematic review. J Periodontol 2005; 76 (8):1227-1249.