Debate Lingers Over Role of Lasers in Periodontal Therapy

Laser-assisted periodontal therapy has been used for many years with controversial results among clinicians and scientists. Knowledge of laser wavelengths and their properties as well as laser–tissue interactions is essential for selecting the appropriate laser system for patient treatment. Glass laser fiber-optics and hollow guides or articulated arms deliver laser energy to the periodontal (and peri-implant) tissues, and, depending on the clinician’s goals, it is possible to perform tissue ablation (laser curettage), vaporization (de-epithelization), reduction of bacteria (specifically periodonto–pathogenic for some laser systems), and—last but not least—sufficient calculus removal. This is revolutionary in clinical practice for soft-tissue applications associated with blood coagulation, providing sealing of blood vessels and nerve fibers in the excision area and leading to decreased postoperative pain and complications. These beneficial effects improve patient comfort and afford clinicians an alternative to the conventional scalpel.

When laser irradiation is delivered cautiously, the regenerative potential of lasers is high, and, undoubtedly, new fibroblastic activity in the connective tissue promotes new connective tissue attachment.¹ This can be established clinically when epithelial migration within the sulcus is removed, simultaneously allowing migration of the connective tissue cells and coronal attachment of a newly formed long junctional epithelium. Numerous animal and clinical reports present this concept as a treatment of choice, especially using the carbon dioxide (CO₂) laser, but also other glass fiber-assisted systems.

I started using various laser systems 23 years ago and have noticed recently that clinicians are attempting to use laser technology without adequate training—a weekend CE course does not suffice. There appears to be a focus on promoting lasers and having private practices use them as a marketing tool. I suggest that laser users focus on learning more about the physics behind them and train to achieve a competency level for soft-tissue ablation, coagulation, and laser–hard-tissue interactions. Only this kind of education will bring clinicians fruitful results in periodontal therapy.

An interesting and beneficial application of lasers is in bone and in peri-implant tissues. Laser-assisted peri-implant therapy allows positive effects in the treatment of peri-implantitis and the decontamination of peri-implant tissues and implant surfaces, improving bone healing and establishing reosseointegration. Certainly, there are no clinical studies available today since it is not possible for ethical reasons to develop randomized controlled clinical trials (RCTs); however, there are case series that demonstrate advantages of the use of CO₂ lasers in peri-implantitis treatment.^2,3 The physical properties of wavelengths of other lasers, such as the neodymium:ytrrium aluminum garnet (Nd:YAG) (1,064 nm) and diode (810 nm to 980 nm) lasers, may be potentially dangerous, because they can melt metals (implants) and can be associated with overheating.

In addition, the use of photodynamic therapy (combination of laser technology and laser wavelength-specific photosensitizers) is a promising concept in periodontal and peri-implant therapy in surgical/non-surgical periodontal treatment, especially in maintenance.

Advanced clinician training and cautious treatment protocols are necessary in order to control intra- and postoperative complications. Dental laser manufacturers should support continuous and more advanced laser training for clinicians along with laser research. Additionally, the curriculum advancement in dental schools in pre-doctoral and postgraduate levels should start incorporating education and training of young dentists with this exciting technology.

Dr. Yukna

While lasers are playing an increasingly significant role in the treatment of periodontitis and peri-implantitis problems, generalized adoption of this technology has been somewhat slow. A variety of laser wavelengths and types have been promoted for the treatment of periodontal pockets, yet some 20 years after the introduction of dental lasers, only one technology and protocol has been shown to have consistently positive clinical and supportive histologic results. The laser-assisted new attachment procedure (LANAP^®) (Millenium Dental Technologies, Inc., www.lanap.com), using a free-running pulsed Nd:YAG laser in an established, patented, single-treatment protocol, has shown consistent short-term and long-term clinical results and uniformly positive histologic results in humans demonstrating cementum-mediated new connective-tissue attachment.^4,5 This minimally invasive surgical approach to periodontal and peri-implant pocket surgery also results in less patient morbidity (eg, decreased pain, virtually no swelling, no bleeding) than traditional periodontal surgical therapy, according to the author’s personal experience as well as data from a multicenter study that is being compiled though not officially available yet.

Although diode-, carbon dioxide- (CO₂), and erbium-based lasers (which I use for other procedures) are promoted and used to some extent for the treatment of periodontal pockets, none of these wavelengths have sufficient data (and certainly no human histology) at this time to justify their claims. They are, at best, an adjunct to nonsurgical periodontal therapy, for use either as an additional step during periodontal surgery or for decreasing the microbial contents of pockets. More research and data are needed with these modalities to justify their claims and warrant their use.

Moving forward, definitive periodontal and peri-implant pocket therapy will increasingly include the use of lasers. At this time, LANAP using the PerioLase MVP-7^® Nd:YAG laser (Millennium Dental Technologies, Inc.) is the author’s procedure of choice and is setting the pace in the progression of laser use in periodontal therapies.

Dr. Serio

Sometimes I wonder if lasers have had more impact on the treatment of periodontal disease or on the behavior of periodontists. Since the advent of the laser-assisted new attachment procedure, or LANAP^®, there seems to have been as much discussion about the pros and cons of this type of therapy as there are treated patients. A proof of principle article in 2007 showed that regeneration is a histologic possibility using the Nd:YAG laser along with the rest of the protocol, which includes meticulous scaling and root planing and occlusal adjustment.⁴ In a 2012 article, an investigation of 12 teeth treated with the LANAP protocol, including systemic antibiotics and prophylaxis at 1.5-month intervals, found that of 10 teeth analyzed with histology, “five teeth evidenced a degree of periodontal regeneration…one tooth had new attachment…and four teeth healed via a long junctional epithelium.”⁵ This is only a 60% success rate of any histologic evidence of regeneration. Six of 12 teeth had residual probe depths of 5 mm or greater. This contrasts with a significant amount of rhetoric espoused by some LANAP proponents that seems to imply that all other approaches to periodontal treatment are outdated and not the “standard of care.”

Long-awaited multicenter 6-month data on LANAP was presented at the recent American Academy of Periodontology annual meeting; full-year data will be presented at the 2014 meeting later this year. In private conversations with periodontists who selectively use this procedure, I have been told that, just like every other treatment modality, case selection is the key. When LANAP works, the procedure is very effective, but it is not the silver bullet. Also, several clinicians have mentioned that while early results are good for LANAP, recurrence of pocketing and disease is more than a chance finding. While there is much talk about the merits of LANAP, some who have used the procedure are not completely sold on their investment. To complicate matters, companies that market lasers of different wavelengths are jumping into the fray, and although these companies themselves have been cautious with their claims, some clinicians are extolling the virtues of treatment with other wavelengths at a lower cost.

Finally, I, along with other colleagues, have noticed on more than one occasion where patients treated non-surgically with vigorous scaling and root planing, occlusal adjustment, and antibiotics have shown subsequent radiographic bone fill of vertical defects. Prichard procedure anyone?

Dr. Yukna has received research support and honorarium from Millennium Dental Technologies and BIOLASE Technologies, Inc. and also serves as a consultant for these companies.

Georgios E. Romanos, DDS, PhD, Prof Dr med dent
Professor and Associate Dean, Clinical Affairs, Stony Brook University, Stony Brook, New York; Chairman, World Federation of Laser Dentistry (WFLD), North American Division

Raymond A. Yukna, DMD, MS
Professor, Advanced Periodontal Therapies, University of Colorado School of Dental Medicine, Aurora, Colorado

Francis G. Serio, DMD, MS, MBA
Dean, Bluefield College School of Dental Medicine, Bluefield, Virginia; Diplomate, American Board of Periodontology