Dr. Fischer responds:
Dan Fischer, DDS
South Jordan, Utah
Dr. Bernard, I was happy to see that you wrote a letter in regard to my treatise of amalgam and composite. At least you are evidence that one of my efforts has been achieved - namely "for the purpose of stimulating thought" as shared in said treatise. I am also saddened that it appeared to have such a negative impact on you. Much of what was shared in the treatise is indeed fact supported by scientific studies as well as clinical success of thousands of dentists in the United States and around the globe. Additionally, some countries have moved significantly away from the use of amalgam while others (e.g. Switzerland) have completely eliminated its use. All of these dentists cannot be basing their logic for successful change on the "supermarket tabloids, fiction, or poetry" that you alluded to.
I love my profession of dentistry as evidenced by my excess of 25 years in practice. I have always taken my education seriously and continue to maintain strong ties with the high-quality, caring professors of my alma mater, many of whom still place posterior amalgams.
For the first 15 years of my practice, I also placed nothing but amalgam as my posterior, direct-restorative material of choice. There are benefits and negatives to amalgam, both of which have been reported in scientific and clinical literature. Some of your claims regarding amalgam are well-founded, while some of your remarks are sorely in ignorance.
Here are some facts:
1. Throughout the 20th century, amalgam helped millions to keep their teeth. It will continue to help people for at least the beginning of the 21st century. However, amalgam-restorative treatment - complete with the need for removal of solid, healthy dentin and enamel simply to interlock, support, and resist the movement of a nonbondable material - is in nearly the same state of technological progress as it was 100 years ago. I`m sure most dentists don`t need me to cite bibliographic quotes to know and understand how old G.V. Black`s constitutions of that time are. We can improve amalgam restorations considerably by using dentin-bonding agents with them, but not nearly to the potential of a material of similar resin base which can intimately bond with the adhesive bonding hybrid layer.
2. Recent studies have taught us that we can bond to dentin at incredibly high strengths which were never thought possible until recently. In fact, we can bond to dentin at strengths two to three times the magnitude of what can be achieved to enamel, depending on the adhesive system. The biggest surprise in these studies was finding that dentin is two to four times stronger than what we thought possible just a few short years ago. Dentin is the strongest material in the human body; it is a virtual calcium hydroxy apatite concrete of mineral reinforced with rebar collagen. Dentists are now achieving results never thought attainable. Yes, there have been failures along the way, just as there have been amalgam failures as well.
3. Amalgams have been in existence longer than composites, but look at air travel. Do you realize that for the first 35 years of air travel, there was much more known about the predictability and safety of land travel than flying? Fortunately, the pioneers of this mode of transportation did not give up on the valued new method. In a like manner, there are certainly more long-term studies available on amalgam than on composite. However, it is not accurate to say there is no scientific evidence to support bonded composite use.
4. Seventy-five percent of amalgams placed are replacements for prior placed amalgams. Total replacement is required, as we all know that soft amalgam doesn`t adhere to set amalgam. Some of the replacements are due to new areas of decay unrelated to the existing amalgam filling, yet most is recurrent decay originating at or below the margin of the filling and progressing inward. This demonstrates that the corrosion compensation "benefit" of amalgam is not a panacea. This is not to say that decay past the margin of a bonded composite couldn`t occur but, if the restoration is adhesively sealed and bonded, migration between filling and tooth is virtually impossible. Bonded composites are not a panacea, either. In fact, to appreciate their benefits, clinicians must make serious study and learn how to properly use them.
5. Current generation high-quality bonding agents can bond quite well to an existing composite restoration. The adhesive strength of these is not equivalent to the cohesive strength of the composite, but even at 50 percent of the strength, the realities for less invasive, high-quality repairing vs. total replacement are totally exciting. Because trauma to teeth is additive, every time we totally replace a restoration, additional insult is caused to the tooth. With life expectancy constantly increasing, it`s important that we practice the most conservative and least traumatic dentistry possible so that our patients may enjoy their lives with their own teeth.
I am passionate about our profession. I have a son and a daughter currently in dental school and a 13-year-old son who swears he`ll join the ranks as well. They are convinced - just as I am - that dentistry is the best profession in the world. Of course, the new and future technologies are exciting, but even more than that is the fact that dentistry is a "people profession" unsurpassed by any other. We build our practices with fellow humans who many times become virtual extended family. It is because of these wonderful relationships that we strive to provide the absolute best for our patients. The new technologies can be used to improve the quality of their lives in ways our predecessors never dreamed. We are a fortunate group. We hurt ourselves as much as our patients when we don`t wake up and smell the 21st-century roses! We cannot, nor should any one at any point in time, be complacent. Remember this: Complacency has a much greater chance of occurring during apparent comfort than in the face of the storm. None of us need or want the storm.
Dr. Bernard, we (at Ultradent Products) host several educators` programs each year in Salt Lake City. Four of these are for dental school faculty and prominent lecturing dentists, principally North American, but there are a sprinkling from Europe. One is dedicated to Latin American, Spanish-, and Portuguese-speaking dentists and educators, while another is for our Asian neighbors. We all work hard for two or three days, including hands-on participation segments complete with laboratory testing as well as didactic. I invite you, Dr. Bernard, to come as my guest. Just as my other guests, we will pay for your travel, room, and board. We will treat you with kindness and respect. I only ask that you come with an open mind and be willing to share your opinions in a professional manner. Should you choose to accept my invitation, I would ask that you write a report on your experience for this journal. What you choose to report is up to you. After all, this is America!