News
Alexandrite lasers for dental applications
BIOLASE root canal therapy
Technoology4Medicine diode lasers
Ivoclar’s “polywave LED” technology
Notes
Ultra-compact diode lasers
Syneron’s LiteTouch laser
New Fotona web site
DIAGNOdent use with sealants
Lasers in restorative dentistry
LLLT laser
Elexxion lasers marketed by Patterson Dental
Survey on dental diode laser usage
Free Articles
Dental diode lasers
Erbium lasers in dentistry
Pulsed Nd:YAG lasers
CO2 lasers in dentistry
LED curing sources
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News
Alexandrite lasers for dental applications
April 14, 2008 (Mercerville, NJ) - Laser Energetics, a manufacturer of compact frequency-doubled alexandrite lasers for industrial marking applications, announced it has filed a patent application covering its BrightStartm alexandrite laser technology. BrightStar is a flashlamp-pumped, conductively air-cooled alexandrite laser (has no internal water cooling loop). The company indicates that BrightStar lasers achieve wall plug efficiency of 5%, and that they can be built to be one-third the size of comparable lasers with internal water loops. The laser will be marketed for teeth cleaning applications by HygeniLase Inc.
January 29, 2008 (Mercerville, NJ) - Laser Energetics Inc. announced it has received an order worth $550,000 for the company’s BrightStartm alexandrite lasers from HygeniLase Inc., a joint venture between LEI and Lantis Laser Inc.
December 4, 2007 (Mercerville, NJ) - Laser Energetics, Inc. (LEI) announced it has an agreement to form a joint venture with Lantis Laser, Inc. (LLI; Denville, NJ) that will market LEI’s alexandrite lasers for dental applications. The laser will be used initially for non-contact laser removal of calculus (bacterial tartar) from teeth, above and below the gum line.
BIOLASE root canal therapy
April 10, 2008 (Irvine, CA) - BIOLASE Technology Inc. announced the global launch of its Endolasetm RFT Root Canal Therapy System. This is a complete laser-based treatment for root canal therapy that employs the company’s WaterlasetmYSGG lasers to access, clean, shape, and disinfect root canals. The laser is used with highly flexible endoTipstm that are about two to three times the thickness of a human hair, and emit laser energy in a radial pattern.
Temple University researcher, Dr. Roy Stevens, indicates that the laser can reduce the level of infection by up to 99.7% percent in root canals and in adjacent infected dentin. He also indicates that the new procedure is significant because the laser can treat bacteria that are highly resistant to other disinfection methods, the laser can disinfect at a distance into adjacent dentin, and the laser can achieve a high level of disinfection in two to three minutes (compared to 20 to 30 minutes using conventional hypochlorite bleach), thus saving considerable chair time during endodontic treatments.
BIOLASE indicates that a peer-reviewed clinical study has shown that the Endolase RFT method eliminates bacteria more effectively than conventional bleaching methods. Contact BIOLASE for details of this study.
Technology4Medicine diode lasers
February 28, 2008 (San Clemente, CA) - Technology4Medicine LLC announced it will be offering in the United States FOXtm dental diode lasers manufactured by A.R.C. GmbH. These lasers provide 810, 980, and 1064 nm wavelengths and power levels to 9 watts. Technology4Medicine is a new company founded by Jeffrey Jones and Keith Bateman, who are former BIOLASE executives. More information is available at www.t4med.com.
Ivoclar’s “polywave LED” technology
February 26, 2008 - Ivoclar Vivadent announced that its bluephase LED curing lights will be equipped with its new “polywave LED’ technology, which provides curing performance comparable to that of a halogen lamp. Polywave LEDs provide broadband emission in the 380 to 515 nm range that is suitable for use with all curing initiators. More information is provided at: http://www.ivoclarvivadent.us.com....
Notes
Ultra-compact diode lasers
Ultra-compact surgical diode lasers have appeared on the scene
that are extremely lightweight and portable. These products have a main body
that can be held easily in one hand. Products typically provide about 3W at
800, 940 or 980 nm wavelengths, but some products provide as much as 7W.
Examples include Biolase’s ezlase, ConBio’s Micro 980, Sirona’s SIROLaser,
and Ivoclar Vivadent’s Navigator.
Syneron’s LiteTouch laser
Syneron has introduced a unique Er:YAG laser, LiteTouch, in
which a miniature Er:YAG laser head resides in the treatment handpiece. The
handpiece is coupled to the main body of the laser with an optical fiber-like
accessory - not an articulated arm. This eliminates the need for a long length
of infrared fiber while providing the same ergonomics as fiberoptic delivery. (Editors note: It is our understanding that the LiteTouch is a lamp-pumped Er:YAG laser that incorporates the flashlamp and Er:YAG laser rod in the handpiece itself. Laser energy is delivered to tissue by micro-mirrors also included in the handpiece. A flexible umbilical cable linking the handpiece and main power unit provides electrical power and cooling to the handpiece).
New Fotona web site
The new Fotona dental web site www.fotona.com/en/dentistry includes two relatively new articles of interest. One article describes combined use of Fotona’s Fidelis Plus III laser and the CEREC 3D device to make inlays and crowns. The author, Dr. Thorsten Kuypers, suggests that advantages of laser-prepared CEREC inlays include treatments with little or no anesthesia, immediate fitting of high-quality inlays, high comfort levels for patients, and extremely correct inlay fits to laser-prepared cavities. This article can be accessed at: http://www.fotona.com/media/objave/priponke/clinical_bulletin__1_cerec_kuypers.pdf
Another article, authored by Dr. Janez Diaci and published by the Journal of Laser and Health Academy, describes the results of an in-vitro study comparing the ablation rates of Er:YAG and Er,Cr:YSGG lasers in dentin and enamel. The study uses a new laser-based profilometry technique to measure laser ablation volumes. The author suggests that the new method provides a more realistic comparison of ablation rates according to how laser handpieces are used in clinical practice. Of particular interest is the data presented on how laser pulse shapes and pulse durations differ between two commercially available erbium lasers (Fotona’s Fidelis Plus III and BIOLASE’s Waterlase MD) and how absorption in dental and enamel differs for these two laser wavelengths. This article can be downloaded at: http://www.fotona.com/media/objave/priponke/2008_2_profilometric_comparison_eryag_ercrysgg.pdf
DIAGNOdent use with sealants
The February 2008 issue of Dental Products Report magazine (Advanstar) includes an article (page 66) describing how the DIAGNOdent™ (KaVo) laser caries detection device can be used to monitor caries progression through clear pit-and-fissure sealants. The authors suggest that having the ability to detect developing lesions beneath sealed surfaces might render some practitioners less reluctant to use sealants.
Lasers in restorative dentistry
A three-part article written by Dr. Robert Lowe appeared in the January, February, and March 2008 issues of Dental Product Report magazine (Advanstar). Dr. Lowe describes the use of lasers for tissue recontouring, gingival hyperplasia, esthetic gingival-level correction, inflammatory tissue control and troughing, frenectomy, Class II cavity preparation, incisal edge restoration, Class V cervical erosion and root desensitization, bone recontouring and surgical removal, elimination of excessive gingival display, surgical crown lengthening (open and closed methods), alveoectomy prior to tooth extraction, and laser pulpectomy and root canal therapy.
LLLT laser
The MediLaser AlGaAs seminconductor laser is intended for numerous low-level light therapy applications (LLLT). The web site includes a list of published positive double-blind clinical studies relating to treatment of allergic rhinitis, arthritis, epicondylitis, herpes simplex, pain, and sinusitis, among other applications. See: HYPERLINK "http://www.laserlight.biz/products_MediLaser.html" http://www.laserlight.biz/products_MediLaser.html
Elexxion lasers marketed by Patterson Dental
The Elexxion Claros diode laser is now marketed in the United States by Patterson Dental Supply. Claros is an 810 nm laser that provides up to 30W output power. More details are provided in DAAL-2007.
Survey on dental diode laser usage
The May 2007 issue of Dental Products Report magazine (Advanstar Dental Media) included a survey article by Stan Goff on the use of diode and other lasers by general practitioners. Some of the more interesting findings were: 56% of respondents use diode lasers; 90% of respondents use lasers for gingival contouring (percentages reported for twenty other applications, performed with diode lasers or other lasers), 90% of respondents perform 1 to 5 laser procedures per day; 57% of those who plan to buy a laser within the next year plan to buy a soft-tissue laser; 18% of respondents plan to buy a laser within the next year; 74% of those who said they do not plan to buy a laser within the next year cited cost as the main reason (too expensive).
Free Articles
Dental diode lasers
Like transistors and related electronic
components, diode lasers are solid-state devices made out of semiconductor
crystals. Diode lasers are similar to the light-emitting diode (LED) display
components used in many electronic appliances in that they emit light when
electric current passes through them. However, diode lasers emit light that is
much more directional, coherent, and monochromatic than LED emission, which
allows diode laser light to be focused to small spot sizes as needed to perform
laser surgery.
Diode lasers used in dental/oral surgery
include aluminum gallium arsenide (AlGaAs) lasers that emit at a nominal
wavelength of 800 nm, and indium gallium arsenide (InGaAs) devices that emit at
a nominal wavelength of 940 nm or 980 nm. Some dental diode lasers provide up
to 20 watts through a 400-micron fiber whereas others only provide 5 to 10
watts.
Surgical diode lasers are used with
hot-tip, contact-mode fiber accessories for precise cutting or vaporization of
soft tissue, or with non-contact fibers for deeper coagulation. Clinical data
suggest that such diode lasers provide essentially the same surgical precision
and hemostasis as 1064 nm CW Nd:YAG lasers in most situations. Accordingly,
surgical diode lasers have found many of the same clinical applications as CW
Nd:YAG lasers of comparable output power. Diode lasers that provide a
940 nm or 980 nm wavelength are relatively new in the field of dentistry.
Some manufacturers claim these wavelengths provide better surgical precision in
gum tissue than 800 nm, because the 940 nm or 980 nm wavelength better
matches a local water absorption peak. More well-controlled scientific studies
that compare 800, 940, and 980 nm diode lasers are needed before a consensus
can emerge as to which wavelengths are best in which clinical situations.
Diode lasers are also used in laser
tooth whitening procedures. In such applications, the laser serves as a highly
controllable heat source for initiating chemical reactions in whitening gel
applied to teeth.
Present diode laser products are not
capable of the same high peak power levels as pulsed Nd:YAG lasers. As a
result, diode lasers are not useful for hard-tissue applications such as
first-degree caries removal (for which some pulsed Nd:YAG lasers have FDA
clearance).
Quartz fibers similar to those used with
Nd:YAG lasers are used to deliver diode laser energy. Once laser energy is
coupled into the fiber, efficient transmission over several meters is possible.
However, it is an engineering challenge to efficiently couple diode laser
energy into small-core fibers; maximum deliverable power at tissue typically
decreases as fiber core size decreases. The numerical apertures (NA) of fibers
used with surgical diode lasers are usually around 0.4 rather than the 0.2 NA’s
typical of dental Nd:YAG fibers. Advances in diode laser technology will enable
increasingly higher power through smaller core and smaller NA fibers.
Surgical diode lasers intended for
dental applications sell in the $7K to $25K range, depending primarily on
output power level and degree of compactness. Many of the latest diode laser
products intended for dental applications are described in Section 8 of DAAL-2007.
Erbium lasers
Due to strong absorption by the collagen, mineral
(hydroxyapatite), and water components of calcified tissue, pulsed erbium:YAG
lasers (Er:YAG, 2.94 µm) can precisely ablate all hard dental substances, at
usefully fast rates, and with relatively low pulse energy and average power.
Even healthy tooth enamel, which is highly resistant to visible and other
infrared laser wavelengths, can be ablated precisely and easily with erbium
laser pulse energies of only 100 millijoules. Higher pulse energies remove
increasing amounts of material per pulse.
Surgical precision and control can be excellent when using erbium
lasers on teeth, but laser dosimetry must be carefully controlled to avoid
photoacoustic damage (tooth micro-cracking) beyond the intended treatment area.
The tooth must also be cooled with a water spray, as when using a drill, to
prevent overheating of the tooth at the laser pulse rates typically employed (10
to 50 Hz). No topical-absorber pigment of any sort is required to ablate
enamel, dentin, or cementum when using erbium lasers.
Erbium YSGG lasers (Er,Cr:YSGG) lasers operate at a wavelength of
2.78 µm and have dental capabilities similar to Er:YAG lasers.
Erbium lasers can also be used to precisely cut and ablate soft
tissue. However, when using fiber delivery accessories in a non-contact mode,
the amount of laser-induced thermal injury is typically so low that relatively
little hemostasis (bleeding control) is provided in most situations. Cuts are
scalpel-like in that there is almost no healing delay, unlike most other
lasers. Erbium lasers are sometimes used with contact-mode, “hot-tip” fiber
accessories to improve their utility for soft-tissue cutting with hemostasis.
Some erbium laser products provide a long-pulse emission mode to improve
hemostasis when cutting soft tissue, and pulse rates as high as 50 Hz to
improve the smoothness of separated tissue edges.
Delivery of laser energy through an optical fiber delivery
accessory greatly facilitates laser treatments in the oral cavity. However,
Er:YAG and Er:YSGG laser wavelengths cannot be delivered through standard
(quartz) fiberoptic delivery accessories as are used with dental Nd:YAG and
diode lasers. Quartz fibers absorb erbium laser energy strongly, and long fiber
lengths attenuate the beam severely.
Fortunately, “infrared fiber” accessories have emerged for use
with erbium lasers. Infrared fibers include sapphire fibers, zirconium aluminum
fluoride, and germanium oxide fibers. These fibers appear to be adequately
reliable, cost-effective, and otherwise appropriate for delivering erbium laser
energy for dental applications. Erbium laser fiber accessories are new enough,
however, that some manufacturers’ fibers may be more reliable than others’.
Manufacturers continue to seek new ways to reduce cost and improve the
reliability of their erbium laser fiber accessories.
Some dental erbium lasers employ articulated-arm (mirror-based)
delivery systems instead of optical fibers. Some laser users find articulated
arms much more awkward to use in the oral cavity than fiberoptic delivery
accessories, but this can vary according to individual preferences. Certain
prospective periodontic and endodontic (root canal surgery) applications of
erbium lasers probably require fiberoptic delivery.
Erbium laser products typically have FDA clearances for
hard-tissue applications on teeth and bone in addition to clearances for
soft-tissue use. FDA clearances may include indications such as caries removal,
cavity preparation, enamel etching for treatments in adults and children,
osseous crown lengthening, apicoectomy, and others. Note that not all products
have the same FDA clearances; contact manufacturers for product-specific lists
of FDA-cleared indications.
Some products combine an Er:YAG laser with a CO2 laser,
or an Nd:YAG laser, in the same enclosure. These so-called “combination laser” systems reduce purchase cost compared to buying two lasers.
Erbium lasers sell in the $50K to $70K range. Combination products
that include an erbium laser and another laser might cost $80K. See
Section 9 of DAAL-2007 for descriptions of commercially available
dental erbium laser products.
Pulsed Nd:YAG lasers
Pulsed 1064 nm Nd:YAG lasers led the modern revolution in laser
dentistry when Terry Myers, DDS and colleagues started American Dental Laser in
the mid-1980’s, and introduced the first pulsed Nd:YAG laser product designed
specifically for dentists. The ability to deliver laser energy through a robust
quartz optical fiber, as needed to cut and ablate minor amounts of soft and
carious tissue, is what made the laser innovative at the time. Pulsed Nd:YAG
lasers continue to be a workhorse for soft-tissue management in dentistry and
are now FDA-cleared for some applications on teeth.
Like dental diode lasers, pulsed Nd:YAG lasers can cut and
vaporize soft tissue with good hemostasis when using bare-tip quartz fibers in
a contact, hot-tip mode. When used in a non-contact mode, soft tissue can be
photo-coagulated as needed to achieve hemostasis over an area, or to treat
lesions such as aphthous ulcers. Fibers are easily re-used by cleaving off the
last inch (or so) of fiber between uses, as is true for dental diode lasers.
Pulsed Nd:YAG lasers generate much higher peak power levels than
diode lasers, and, unlike diode lasers, are FDA-cleared for some applications
on teeth. For example, most pulsed Nd:YAG products are cleared for selective
removal of first-degree, incipient caries in preparation for sealant
application.
The high-peak-power emission from pulsed Nd:YAG lasers is claimed
by some manufacturers to offer treatment capabilities that can’t be achieved
easily, or at all, with dental diode lasers. Early research suggests that the Laser-ANAP® soft-tissue procedure developed by Millennium Dental Technologies can result in
stimulation of new bone growth around teeth. Millennium Dental believes that
such results have not been demonstrated with diode lasers. More research is
needed to fully understand all conditions under which bone regrowth can and
does occur.
Pulsed Nd:YAG lasers intended for dental applications have been
shrinking in size and weight as the technology has improved. Some companies
have done a very good job of making their lasers extremely compact and
lightweight. In the future, diode-pumped Nd:YAG laser technology will result in
even smaller pulsed Nd:YAG lasers.
Another trend in pulsed Nd:YAG dental lasers has been toward
user-controlled laser pulse durations in the 100 to 1000 microsecond range.
Products typically afford the user the ability to select among at least two,
and as many as seven, different pulse durations to customize treatments.
Shorter pulse durations are used when cutting or ablating tissue, and longer
pulses are used for hemostasis and other soft-tissue coagulation applications.
Several companies now offer combination Er:YAG / Nd:YAG laser
products. The Er:YAG laser is used primarily on teeth, whereas the Nd:YAG
modality is used for soft-tissue procedures.
Pulsed Nd:YAG lasers sell in the $16K to $65K range. Products at
the higher end include licensing for patented and specialized soft-tissue
procedures performed with a pulsed Nd:YAG laser. See Section 11 of DAAL-2007 for more discussion of pulsed Nd:YAG lasers used in dentistry.
CO2 lasers in dentistry
Carbon dioxide (CO2) lasers have been used in laser
surgery and medicine since the 1970’s. Their forte is precise cutting and
vaporization of soft tissue, along with good hemostasis, in a non-contact mode.
The “non-contact” capability provides the ability to rapidly treat relatively
large areas of tissue, and areas with uneven surfaces. For this reason, CO2 lasers are often the laser of choice for many periodontal laser specialists.
The earliest medical CO2 lasers were high-power devices
(50 to 100W) and were intended for multi-specialty surgical use in a hospital
setting. Lower power products intended for use in an office setting, including
dental offices, appeared in the mid-1990’s. All such products currently employ
sealed-tube laser designs. Many use RF-excited (low-voltage) laser tubes, but
some use DC-excited (high-voltage) discharges. Output power levels of
office-based products are generally in the 5W to 25W range.
Combination laser products that combine an erbium laser for hard
tissue and a CO2 laser for soft tissue are available. Dental CO2-only
lasers sell for $15K to $25K, whereas combination erbium-CO2 lasers
sell for $60K to $80K. See Section 7 of DAAL-2007 for a description of
dental CO2 laser products.
LED curing sources
LEDs are similar to diode lasers except
that LED semiconductor chips are fabricated without the resonator micro-mirrors
that diode laser chips have. This reduces cost compared to diode lasers, but
LED beam quality is typically much worse than that of a diode laser. LED beams
can’t be focused to the same small spot diameters as diode laser emission. LEDs
are generally limited to applications that can be done without delivering light
through a single optical fiber - a bundle of multiple optical fibers or a
large-diameter glass lightguide is used. Alternatively, LED emission may
directly illuminate tissue without any intervening fiber optics. (Some
diagnostic instruments may employ a low-power LED mated to a single multimode
optical fiber because coupling efficiency is not important for device
operation).
Only recently have blue LEDs been able to provide enough power,
and at low enough cost, to be considered for dental curing and related
applications. The technology has evolved very rapidly. Present blue LEDs
provide about 5W of power in the 400 to 490 nm range, at intensities of 1000 to
2000 mW/cm2, which is enough to compete with halogen lamps for
many curing applications. Wavelengths in the 440 to 490 nm range are used for
curing CQ-based resins and composites, whereas 400 to 430 nm wavelengths
are used for PPD-based materials. Some products incorporate two LEDs in the
same unit that, together, provide emission over the entire 400 to 490 nm
wavelength region.
Curing LEDs sell in the $400 to $1500 range, depending on power
level, number of wavelengths offered, and specific features offered. See
Section 12 of DAAL-2007 for a table-style summary of more than 40
different curing LED products.
Disclaimers
This page is intended for informational and educational purposes only. JGM Associates, Inc. does not endorse or recommend specific products or uses of products. In all cases, practitioners who use lasers should complete an accredited training course, approved by the manufacturer, before attempting to use any laser product or related accessory. The reader should note that not all products have FDA clearance or approval for the same clinical uses.
Information has been obtained from sources believed to be reliable. While JGM Associates believes the data provided herein to be accurate, no expressed or implied guarantees are made regarding accuracy or adequacy. Product- and company-related data can change very quickly and without notice. The interested reader is encouraged to contact manufacturers directly for their latest information.
JGM Associates, Inc. reserves all rights to this copyrighted document. This report may not be reproduced in part, or in whole, without permission of JGM Associates, Inc.
Product names listed in italics are the trademarks or registered trademarks of the companies whose names appear with the product names.
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