From: Rob Kaufmann
To: ROOTS
Sent: Friday, January 02, 2009 9:24 AM
Lasers in Dentistry
( From the Schilder Gianelly Symposium Boston 2004) by Robert Kaufmann
Dr. Stabholz explained the physics behind lasers and how excitation creates
the photons that make up the coherent light. The problem with
"open ended fibreoptics" is that the laser energy is directed "forward" at
the end of the fiber and can result in rapid heating. He showed a video of
how, when a normal laser fibreoptic was touched to photosensitive paper
(like old style thermal fax paper), it quickly burned. Obviously, this
wouldn't be of use in a canal. Dr. Stabhotz is currently performing research
with a new side-firing spiral tip for efficient cleaning of the root canal
system by means of lateral laser irradiation. This Israeli produced
Er:YAG/CO2 combo laser is delivered with a uniquely designed tip.
Dr. Stabholz said that other types of lasers (Excimer, Diode) were either
too expensive to be practical or caused charring of dentin. The CO2 laser
is less expensive but also has charring effect except when used at the
specific wavelength of 9.6 microns.) He is currently using the Opus 20.
This is a new Israeli produced (ESC Medical) laser that combines a CO2 and
an erbium laser in one system, and can be used for a wide variety of dental
procedures. The new endo tip looks very much like the old style thick
tapered long "chrome" EIE ultrasonic tips . Instead of a metal core as in
the ultrasonic unit, the laser tip consists of fibreoptic centre that is
covered with a metallic coating. During the manufacturing process a thread
is embedded in the coating in a spiral fashion. The coating dries and then
the thread is removed, forming a spiral space in the coating that emits the
side fired laser along the walls of the canals. He showed how use of this
laser tip in combination with 17% EDTA can create some very nice open
tubules with very clean prepared dentin. Lased dentin without the EDTA
still exhibits debris and smear layer, so it appears that EDTA solution
is necessary. When asked if it was the heating action of the laser on the
EDTA that caused this (as opposed to the laser itself) he wasn't sure.
Controlled tests using this as a comparison with heated EDTA 17% need to be
done. He did indicate that more research was being done on this subject.
What was most impressive about the tip was that it appeared to be simple
to use with a passive in and out motion. Sample teeth had one side cut away
so you could see that the tip did in fact reach the apex of a well-prepared
canal. Further research is in the works. These new side-firing tips appear
to be both sturdy and effective. Assuming that the technology can be made
more affordable, it appears to have potential for greater canal disinfection
and for the creation of an environment that will allow for better adhesion
of filling materials.
Perhaps Glenn could update us on any further results from Dr. Stabholz's
work. He appears to be one of the leading Endodontists that has been
researching lasers for a number of years.
Incidentally, ESC ( now called Lumenis) was producing the
Opus Duo CO2:Er laser but the link on their site is not working and the
product is not listed on the Lumenis website. I do not see Dr. Stabholz's
name associated with any laser products so I assume the Israelis have
given up on the CO2 portion of the DUO laser and are sticking with the
Er version. Glenn? - RobK
OLD NEWS ROB.....2004 for a laser no longer sold, with a tip that was 70
at the end, it couldnt be used for anything more than a canine.
This is what happens when someone is quoting research without any
clinical experience, this tip had one thing that was beneficial and that
was a tip blocked at the end. It was written about in the textbook from
2004 in the chapter on endodontics in laser dentistry.
The tips now are flexible , to a size 30 and NOT put far into the
canals, its all photoacoustics with the laser.
This Israeli produced tips for the OPUS DUO laser which was CO2 and
Erbium combo unit (always breaking down) from Israel but it is no longer
sold in N.America.
CO2 lasers are making a rejuvenation now with Deka and Great Plains
being leaders in the technology because the wavelength is an excellent
Oral Surgical Laser for elimination of leukoplakia and remarkable in its
speed of cut on soft tissue. The new CO2 laser are superpulsed so there
is less charring.
In any event the initial impetus for the work of Colonna and Devito and
here are two photos from their work. In the first JPEG you see the
clean tubules from the laser and in the 2nd one note the collagen fibrils.
Here are his quotes
Once again it's not about the instrument. It never will be. And the
puzzle isn't solved by carving huge apical sizes. It's about
instrumenting just large enough shapes to get bactericidal irrigants and
tissue dissolving irrigants into as much of the canal system as possible
- particularly the critical apical few mm, which nealy always presents
with fins and deltas. It's up to the irrigants to take care of the bugs
and thier substrate - not the instruments. "
and
One of the goals is to not thermaly heat the dentin in such an enclosed
space like a root canal system. If you rely on photonic energy alone,
you can have that happen. The collagen fibers that support the dentinal
matrix are usually the first things destroyed. But if you can harness
the photoacoustic action, with the use of very low energy, by modifying
the laser tips to help you, you can get this:
Finally , I do know that Mark is successfully doing endodontic therapy
WITHOUT A SINGLE ROTARY FILE.....basically he is just removing the pulp
tissue out of the tooth and also working now on obturation techniques to
obturate the clean pulpal space. I do know that he has successfully
done this and is working clinically on this.
As I mentioned I hope that this information at least you look at this
and take a course on lasers so that you can at least understand
elementary laser physics and why wavelengths like CO2, diode and NdYAG
might not do more than disinfect with concomitant charring of tubles,
and melting of them whereas the Erbium wavelength might be more
effective , safer and indicated for endo. Its all about wavelength,
chromophores, power settings, tip design etc. - Glenn
Glenn, It is a well-know fact that we need to be cautious in interpreting
SEM images. I have almost sure that the 2 SEM images that you posted are
related to dentin areas where the instruments were unable to touch the
dentinal walls – it is easy to observe it because the dentinal walls are
not planed. So, without dentin cut there is no smear formation. These
areas are often found in SEM without difficulty.
Please see the attached SEM pic where on the right side of the image,
the instrument doesn't cut the dentinal wall and, as a consequence the
tubules are patent even without the use of any chelating solution. But,
on the other hand, on the left side of the image, a smear-covered dentin
is shown just because it was cut (there is planed appearance). I guess
that the right side of my image is very close to the image that you
have posted.
Although its use is very common, SEM is currently well-known as a
treasonable and unreliable method; in fact, the information provided
by SEM must be confirmed by further methods
Healthy skepticism is great.....what if no instruments were used in the
removal of the bacteria. Then what. Wouldnt this be cool if the lasers
could remove the pulpal tissue and bacteria without mechanical
enlagement, and obturated without mechanical enlargement.
Would that not be the epitomy of minimally invasive in the endodontic
field. Enlargement for post prepration only.
Interesting hmm.......keep your eys open.
I havent got time to argue this anymore, keep on doing the same old thing.
The mind is like a parachute it only works when its open.
but
The teacher must appear when the student is ready.
Email me when you are ready.
Warmest Regards from snowy Vancouver - Glenn
How about a laser for apical surgery? - Oliver jones
If lasers can "sterilize" (and I don't trust that term) a root canal
system, than it is a grand-slam home run, world cup championship,
for endodontics. - Fred
Greetings my friend.....lasers are great for "bacterial reduction" to
the tune of 99.7% in 120 secs...
What term we use for that I will leave up to those with sharper minds
than me! - Glenn
......How about a laser for apical surgery? - Oliver jones.....
The student is ready......
I have met Dr. Reyhanian, he is a great clinican pushing the power of
his Kavo Key 3 for all sorts of osseous removal for implant placement
and amazing cases of perimplantitis. His articles are amazing and he
does alot of his work through the microscope ( a rather primitive one
without inclinables ) and he captures great video. Truly a great
presenter, he is way ahead of his time. If you get a chance to see what
he is doing with erbium lasers for disinfection, removal of granulation
tissue around failing implants and for removal of hydroxyapatite
coatings withbout damage to the titanium (eribums are absorbed in water
and hydroxyapatite as chromophores) it is pretty incredible.
Hope that this article helps....there is a link to the full article here
http://www.nature.com/bdj/journal/v205/n6/abs/sj.bdj.2008.804.html
Here is the abstract - Glenn
Br Dent J. 2008 Sep 27;205(6):319-23.Click here to read Links
The use of the erbium yttrium aluminium garnet (2,940 nm) in a
laser-assisted apicectomy procedure.
Reyhanian A, Parker S, Moshonov J.
If conventional endodontic treatment is not possible or not
successful, apical endodontic surgery may be indicated. New techniques,
materials and technologies have been used to increase the already high
success rate of root canal treatment. The purpose of this article is to
describe the use of the Erbium:YAG (2,940 nm) laser in treatment of
apicectomy as a central tool, with the advantages of enhanced patient
comfort, better bactericidal and decontamination effects.
Comentários
Postar um comentário