Lasers with Dr. Mark A. Latta and Dr. Tim McVaney
Dr. John Jameson
This month, Dr. John Jameson speaks with Dr. Mark A. Latta and Dr. Tim McVaney regarding lasers. Dr. Latta is associate dean for research and continuing education and an associate professor in the department of comprehensive dental care at the Creighton University School of Dentistry. Dr. McVaney is associate professor of periodontics at Creighton.
This is the first of a two-part series on lasers in the dental office. Part I deals with lasers in the academic setting and early research of the tool. The next installment will examine clinical implementation and usage of lasers on a daily basis.
Dr. Jameson: From the literature today, there appears to be a tremendous increase in researching lasers with dental applications. What are some of the primary varieties being researched, and what uses are being explored?
Dr. Latta: Over the last 10 years, we have seen an explosion of work in researching the application of laser technology to dental practice.
There are two general classes of lasers, and both have current and potential applications for the dental practice. So-called "hard" or "hot" lasers are characterized by high-energy output and are used for soft-tissue surgery and tooth-related procedures. The principal lasers in this category include the carbon dioxide (CO2), argon, neodymium-yttrium-aluminum garnet (Nd:YAG), and the erbium-yttrium-aluminum garnet (Er:YAG) lasers. The dentist`s primary uses of these lasers include soft-tissue surgery, coagulation, polymerization of visible light-cured materials, conditioning tooth enamel for bonding, caries removal, and, most recently, the approval of the Er:YAG laser for hard-tissue cutting for cavity preparation.
At the opposite end of the energy spectrum are the so-called "cold" or "soft" lasers. These lasers have been advocated for use in what is broadly termed as "low-level laser therapy" (LLLT). These lasers are thought to stimulate cellular activity, and it has been suggested that they are useful in enhancing tissue regeneration and wound-healing. Diode-laser devices and helium-neon (He-Ne) gas lasers are the main examples of lasers used for LLLT. However, a clinical claim of these lasers` efficacy remains controversial.
Dr. Jameson: How will these applications directly affect the quality of care the clinician can provide?
Dr. Latta: The use of lasers for tissue surgery has clear advantages to both the patient and the dentist. Because the laser cuts and coagulates at the same time, the surgical field can be more clearly visualized and little, if any, bleeding occurs.
A surgical laser beam can be adjusted to a fine line for creating incisions. It can also be broadened to remove tissue over a larger area, which allows greater control and more flexibility than electro-surgery or a conventional scalpel.
The polymerization and tooth-conditioning applications of argon lasers provide the principal advantage of equivalent quality in less time compared to a typical polymerization light or tooth-conditioning agents. In addition, the use of an Er:YAG laser for cavity preparation and caries removal may, in some cases, eliminate the need for using local anesthetic for the tooth being restored.
While the use of LLLT is not yet fully proven, the application to wound-healing may provide a modality for significantly improving recovery from dental surgical procedures.
Dr. Jameson: What were some of the first indications of how lasers would be used in clinics today that you saw?
Dr. McVaney: In the last four years, argon lasers have given us the opportunity to work with tissues, which allow us to take a "plastic-surgery approach" to correct some problems in a comfortable way for the patients. They may often dread the second or third surgical procedure, but the use of lasers allows us to alleviate those fears. Most people walk away telling us it was a comfortable procedure.
The one complication with lasers is that they are much slower than cold steel, but the benefit of contouring tissue to a form where you can ablate it is tremendous. All of the procedures that couldn`t be done because of proximity to teeth can now be accomplished using a laser.
Dr. Jameson: What kind of changes have you seen in the units?
Dr. McVaney: They`re much smaller and cost much less. Lasers used to cost around $45,000; now they`re down to about $15,000, if not less. Once they get into the $7,000-$10,000 range, they will be very acceptable in private practice. As the product drops in cost, dentists will be better able to deliver prosthetics that look like they naturally belong. Lasers will become a product that serves the patient and his or her needs very well.
Dr. Jameson: As newer technologies are integrated into the practice environment, each must have a system of use to positively influence the bottom line. To what level do you feel that laser use can improve profitability of the practice?
Dr. Latta: It is difficult to quantify the "bottom-line" benefit to a dental practice based on the use of lasers. Certainly providing high-quality care faster will impact a practice`s profitability, but the perceptions of the dentist and the patients also are important in intangible ways to the practice`s overall health.
The soft-tissue applications generally provide a better and faster result than alternative techniques. However, lasers generally cost more than other devices used in soft-tissue surgery, and the overall economic benefit will depend on the individual practice.
In my opinion, the real treatment and economic benefits of using lasers in dentistry is still ahead.
Dr. Jameson: Even though specific research programs have searched for defined results, what "spin-off" information provides even more benefit to incorporating a particular variety of laser in the treatment mix?
Dr. Latta: One of the most exciting "spin-off" discoveries with the "hard" lasers has been the potential for use in preventive dental procedures. There is mounting evidence that use of these lasers - particularly the argon laser for relatively short and low-energy exposures - can significantly decrease the solubility or demineralization of enamel. This could lead to a new application for treating the margins of restorations, cervical abfraction lesions, or smooth enamel surfaces in caries-risk populations, thereby reducing new or recurrent caries. This could lead to both higher quality care and more profitability.
At the low-energy side of lasers, there exists the potential for the destruction of bacteria without the risk of high heat generation. The term "lethal laser photosensitization" has been coined to describe the process where laser radiation, emitted from a low-power laser, is used to activate a dye which has been absorbed by a targeted bacterium. The dye activation leads to the death of the organism without harming the adjacent hard or soft tissues. This could have significant applications for caries control and endodontic and periodontal therapy.
Dr. McVaney: We are currently involved with some studies regarding very deep curing on impacted cuspids. We have been able to completely expose the cuspid, ablate the tissue around it - so there wasn`t much bleeding - then cure. It`s amazing how the adhesives have remained attached.
Dr. Jameson: What does the future of lasers in the clinical environment have in store for the dental profession?
Dr. Latta: In my opinion, the future bodes well for the development of new and clinically valuable uses of laser technology. As manufacturing improvements reduce the cost of lasers and new research expands their use, both patients and practitioners should reap the benefits of focused laser energy.
Dr. McVaney: In terms of soft-tissue management, I`m looking forward to seeing lasers enter into the practice. Dentists will have much more control in situations that are now seen as complicated. Sometimes patients present practitioners with an unmanageable impression situation or difficult areas to control the margin. I think lasers will be a definite advantage here.
I also think lasers will offer a great advantage in terms of esthetics. You`ll be able to modify the contours of the teeth until the patient decides that that is what he or she wants them to look like. We`ll have better control of lesions that have been problems for us in the past. There are many ways that lasers will help the general practitioner.