July/August 2011, Volume 7, Issue 7
Published by AEGIS Communications
As dental lasers enter their third decade of use, new and improved instruments continue to be introduced. The most popular group of soft tissue lasers, diodes, are now available with such features as programmable touch-screen controls so practitioners can easily select their favorite setting, and disposable pre-sterilized tips for convenience and efficient energy delivery. Some models are self-contained with a battery, laser, and handpiece designed into a “pen” shape, requiring no cables or foot pedals. Carbon-dioxide soft-tissue lasers also are now offered with touch-screen panels and very useful tip configuration. Many instruments in both wavelengths feature very short duration pulsing, allowing precise control of the laser thermal action.
A new wavelength, Nd:YAP, has been introduced into the North American market from Europe. It has all of the indications for use of soft-tissue lasers, with the additional advantageous ability to remove separated endodontic instruments in a canal.
There have been improvements to some hard tissue lasers as well, with better handpieces and tips. In addition, there are new applications for periodontics, such as calculus removal, and endodontics, such as canal cleansing.
One of the main benefits of dental laser use is the lasers’ ability to reduce the amount of bacteria and other pathogens in soft and hard dental tissues. During soft-tissue surgery, all lasers achieve good hemostasis, reducing the need for sutures and minimizing the possibility of scar formation. The other main advantage is that lasers can selectively and precisely interact with diseased tissues. Lasers can debride and coagulate inflammatory granulation substances during periodontal procedures, while not interacting with surrounding healthy tissue.
Erbium lasers can have some selectivity when removing diseased tooth structure, because a carious lesion has higher water content than healthy tissue. Osseous tissue removal and contouring also can proceed easily, and the resulting surface has no smear layer. Moreover, studies have shown that lased enamel has good potential for bonded restorations if they are subsequently acid-etched.
There are some disadvantages to the current dental laser instruments. Special safety precautions must be employed, including wavelength-specific eyewear for everyone within the exposure distance of the laser beam. Accessibility to the surgical area can sometimes be a problem with the delivery system, and the clinician must prevent overheating the target tissue. Currently available dental lasers only emit energy from the delivery system tip. In that sense, they are all “end cutting,” which usually means a modification of the practitioner’s clinical technique. Although they are useful for caries removal and tooth preparation, the Erbium family of lasers is unable to remove defective amalgam, gold, and cast-porcelain restorations.
The first way to consider a laser purchase is for the practitioner to carefully articulate what procedures are currently performed, then investigate if the laser would add any benefit, such as improving the protocols. Examples include:
- Adjunctive use to treat periodontal disease with good results.
- Soft-tissue retraction for placing direct fillings and capturing impressions for indirect restorations. With the proper parameters, those impressions can be taken immediately after the soft tissue is contoured, with confidence that the gingiva will remain at its treated height and contour.
- Excision of a fibroma or revision of a frenum can be bloodless and comfortable. Generally speaking, sutures are not necessary; the wound will heal well by secondary intention without surgical packing.
- Removal of redundant fibrous gingival overgrowth.
- Treating carious lesions and removing old composite restorations while preserving healthy tooth structure.
- Treating infectious areas without prescribing antibiotics, especially for patients unable to take those pharmaceuticals.
- Additional disinfection during endodontic therapy.
Another approach is for clinicians to ponder adding new procedures, such as crown lengthening, implant uncovering and placement, and esthetic dentistry. Lasers provide versatility and precision in those treatments.
The dentist/potential purchaser should be a wise consumer. He or she should use a checklist for the device, including features, controls, set-up, ergonomics, portability, supplies needed, and sterilization and disinfection protocol. The same scrutiny should apply to the manufacturer to determine the training and support available, the quality of construction and warranty, and customer satisfaction and track record.
As with all dental materials and instruments, the practitioner must use clinical experience, receive proper training for safe operation, become very familiar with the operating manual, and proceed within the scope of his or her practice. Due to the varied composition of human tissue and the differing ways that laser energy is absorbed, there is no one perfect laser. However, for more than 20 years, patients continue to agree that the dental laser is a wonderful instrument.
About the Author
Donald J. Coluzzi, DDS
HS Clinical Professor
UCSF School of Dentistry
San Francisco, California