A tremendous number of laser companies have received FDA clearance for their surgical lasers. Not all that have received FDA clearance for dental indications are actively marketing in the United States at the present time–Cao Laser, Fotona, Sciton, and Lokki to name a few. Here is a brief Cliffs Notes way to check on FDA-cleared laser features and parameters.
WAVELENGTH
Wavelength is the “color” of light that is absorbed (or not!) into target tissue. But wavelength alone does not determine the entire tissue interactions that can take place. It is a critical element, but not the only key parameter.
TEMPORAL EMISSION MODE (TEM)
TEM is how a laser delivers its energy over time…a very key component of tissue interactions. For example, is the energy being delivered like a garden hose of photons “soaking” the tissue with light of one wavelength/color without means to control overflow? This would be a continuous wave (CW) TEM. Or, is the laser delivering pulsed laser light to the tissue that better controls how the stream of photons are entering into and interacting with the target tissue? There are 2 main types of pulsed lasers in dentistry. One type is gated pulsed, where a shutter interrupts a continuous beam of light (like light shining through the blades of a fan). The second is free running pulsed (FR), where the electronics inside the laser cavity allow light out in very intense bursts of approximately 100 millionths of a second (10-6 sec). This is much greater than the average power displayed on the console of the laser device, but with long “off” times to give very low “average” powers and a lot of control of tissue interactions.
DIAGNOSTIC/DETECTION (655 NM RED)
These are visible CW lasers that excite molecules in tooth decay or subgingival calculus; a sensor picks up reflected light and relays a signal back to the device from a probe that alerts the clinician to the presence of decay (DIAGNOdent [KaVo]) or calculus (DetecTar [Ultradent]).
Examples:
• DIAGNOdent
• DetecTar
DIODES (808 TO 980 +30 NM)
These are near-infrared CW lasers that for many soft-tissue surgical procedures require the “conditioning” of the tip to trap photons in the tip, thus heating the tip to 500° to 800°C; this laser “hot glass” effect cuts by melting the tissue. Some diodes can be used in a “high-fluence mode” with water lavage with a cleaved bare fiber (eg, SmilePro 980 [Biolitec]). Tissue conditioning would not be used for treatment of aphthous ulcers or biostimulation. If the lasers have a pulse mode, it would be a gated pulse. The devices are too small and inexpensive to have the necessary elements to generate a FR pulse, and can be used for soft tissue and biostimulation only.
Examples:
• LaserSmile and DioLasePlus (BIOLASE)
• SmilePro 980
• DioDent II Soft Tissue Laser (HOYA ConBio)
• Odyssey Diode Laser (Ivoclar Vivadent)
• Opus5 and Opus10 (Lumenis)
• SoftLase (Zap Lasers)
Don’t forget to check out the features and parameters in each diode device. While similar in tissue response, not all diodes are created equal. For example, the SmilePro 980 has a timer and fluence display that tells the operator how much energy has been delivered to tissue. HOYA ConBio’s DioDent II has a separate/remote power supply that should help with some of the overheating issues diodes can have. SoftLase is very small and inexpensive, and isn’t “overstacked” with unneeded wattage–that should help keep it cooler, too. LaserSmile has lots of nifty features too, including a bleaching wand. So check them out for features and performance that fit your needs.
ND:YAG (1.064 ΜM WAVELENGTH)
These are FR pulsed near-infrared lasers used for selective soft-tissue ablation, dedicated soft-tissue laser with some hard-tissue applications (ie, enamel caries removal), and biostimulation as well. Nd:YAG wavelength represents the first to move to digital electronics versus analog.
Examples:
• PulseMaster 600 IQ (Biolase): single pulse duration
• PowerLase ST6 (Lares Research): 2 pulse durations
• PerioLase MVP-7 (Millennium Dental Technologies): 7 digital variable pulse durations.
ERBIUM YAG (ER:YAG [2.936 ΜM WAVELENGTH])
This is a FR pulsed mid-infrared wavelength that is highly absorbed in water, collagen, and hydroxyapatite (therefore, anything it touches in the human body should absorb it). It is free running only, and there is no CW version on the market. One can’t make a diode of this wavelength and expect it to reach the high peak powers and energy densities to remove enamel. The Er:YAG is a dedicated hard-tissue laser, including bone and soft-tissue ablation; not very selective.
Examples:
• VersaWave (HOYA ConBio)
• OpusDuo dual Er:YAG and CO2 (Lumenis)
• PowerLase AT Er:YAG and Nd:YAG (Lares Research)
ERBIUM, CHROMIUM: YSGG (ER,CR:YSGG [2.790 ΜM WAVELENGTH])
This is a FR pulsed mid-infrared wavelength that uses a chromium-sensitized host crystal of yttrium scandium gallium garnet instead of a YAG crystal (yttrium aluminum, garnet). It is highly absorbed in water, collagen, and hydroxyapatite (therefore, anything it touches in the human body should absorb it). This is a dedicated hard-tissue laser including bone and soft-tissue ablation; not very selective.
Example:
• WaterlaseYSGG all-tissue laser (Biolase): utilizes patented laser-energized water technology (hydrophotonic energy)
Carbon Dioxide
(CO2 [10.064 ΜM WAVELENGTH])
This is a far-infrared wavelength delivered in CW, gated pulse, and recently in FR pulse from Lumenis and DEKA, that is highly absorbed in water, collagen, and hydroxyapatite (therefore, anything it touches in the human body should absorb it). This is a dedicated soft-tissue ablation device; not very selective.
Examples:
• OpusDuo dual CO2/Er: YAG; NovaPulse (Lumenis)
• Smart US-20 D CO2 (DEKA)
GENERALLY SPEAKING
For serious hard-tissue work on enamel, dentin, and bone–with secondary soft-tissue emphasis–you’re looking at one of the erbium devices.
Examples:
• VersaWave (2.97 µm)
• WaterlaseYSGG (2.8 µm)
• OpusDuo (2.97 µm)
• PowerLase AT (2.97 µm)
For serious soft-tissue work in moderate to severe perio, tissue hemostasis, and aesthetics–with secondary hard-tissue emphasis–you’re looking at one of the pulsed Nd:YAG devices.
Examples:
• PulseMaster 600 IQ (1.064 µm)
• PerioLase MVP-7 (1.064 µm)
• PowerLase ST6 (1.064 µm)
For soft tissue only, early to moderate perio, fibrous tissue removal, aesthetics, you’re looking at one of the continuous wave (CW) diode devices in either 810-nm or 980-nm wavelength.
Examples:
• SmilePro 980 (980 nm)
• SoftLase (810 nm)
• LaserSmile (810 nm)
• DioDent II (810 nm)
• DioLasePlus (810 nm)
• Opus5 and Opus10 (830 nm)
When considering purchasing a laser, don’t just buy on price…uncover the value for you and your needs.
Dr. Gregg is a past faculty member at UCLA School of Dentistry, Section of Hospital Dentistry. He has been using lasers clinically since August, 1990, including CO2, pulsed Nd:YAG, surgical and photopolymerization argon, and Er:YAG. He has given lectures nationally and internationally on the subject of clinical laser applications, and has conducted seminars for UCLA Department of Continuing Education. In addition to authoring several peer-reviewed articles on the clinical applications of pulsed Nd:YAG for endodontic and periodontal uses, he is an author of the Laser Curriculum Guidelines, versions 1 and 2. Dr. Gregg has obtained his mastership and educator’s certification in the Academy of Laser Dentistry. He is a co-developer and patent holder of the Laser ENAP periodontal technique. He maintains a private practice 4 days per week and may be reached at (562) 860-6587 or rgregg@millenniumdental.com
Disclosure:
Dr. Gregg is a co-developer of the FDA-cleared PerioLase pulsed Nd:YAG laser, and is a founder of Millennium Dental Technologies.
