How to choose the right Laser

2018-04-18 - 8308

Just as you, I was once looking to buy a laser for my dental practice but struggling to choose the right one. Today, laser is an instrument that I cannot live without. If you could use it for just one single day, I’m 100% sure you’d be crazy mad to me taking it away from you.

It’s fun to see how we continue to consider this tool as a new technology. As a matter of fact, the first dental laser was born in the 1960s and, since then, it has always been appreciated by patients.

Fig. 1

Basically, laser is able to cut using light: the pros of laser are the fact that its action directly affects bacteria and supports, at the same time, the body’s healing response.

It is critical to note that laser treatment is an addiction to – not a replacement for – conventional treatments.

It is really important to clarify that the gentle and specific cut has the ability to support the healing process.

Depending on the target we can divide lasers into two groups:

Fig. 2

DIODE wavelenghts

810 to 830, 940, 980, 1064

Soft tissue application: includes wound healing, removal of hyperplastic tissue to uncovering of impacted or partially erupted tooth, in general for all soft tissued cut.

It is Very useful in optical impression , with or with our powder.

Diode deeply decontaminate hard tissues because of its low affinity with water and hydroxyapatite especially when used in addiction with h2o2.

Many dentists think that a Laser is almost an electrosurgery 2.0. I want to make one point very clear: the specific tissue cut and the ability to support the healing process, makes diode laser really different from an electrosurgical scalpel.

Electrosurgery damages minimum 400 cells layers, a Diode maximum 2 to 5 cell layer, thus allowing a faster healing and no colliquation.

 

Fig. 3

Laser can target in a very specific way depending on wavelength (water for erbium and dark pigments as melamine and hemoglobin for diode laser), while electrosurgery is absolutely non specific.

Fig. 4

Hard tissue application: the  used to cut hard tissues, restorative removal and curing , cavity preparation, dentinal hypersensitivity, and decontaminate implants surface .

The most used laser in dentistry for hard tissues is Erbium.

Hard lasers, such as, Carbon dioxide (CO2), Neodymium Yttrium Aluminum Garnet (Nd: YAG), and Er:YAG, which offer both hard tissue and soft tissue applications, but have limitations due to high costs.

 

DENTAL LASERS

Fig. 5

Carbon dioxide Laser

The CO2 laser wavelength has a very high affinity for water, Resulting in rapid soft tissue removal and hemostasis. It has a very shallow depth of penetration.

It has the highest absorbance of any laser; cons of the CO2 laser are its large size, high cost and hard tissue destructive interactions.

Fig. 6

Neodymium Yttrium Aluminum Garnet Laser

The Nd: YAG wavelength is highly absorbed by the pigmented tissue, making it a very effective surgical laser for cutting and coagulating dental soft tissues, with good hemostasis.

Fig. 7

Erbium Laser

The erbium family of lasers has two distinct wavelengths, Er, Cr:YSGG (yttrium scandium gallium garnet) and Er:YAG (yttrium aluminum garnet). The erbium wavelengths have high affinity for hydroxyapatite and the highest absorption of water in any dental laser wavelengths. It is the laser of choice for treatment of dental hard tissues.

Erbium lasers provide minimum heat side effects and can also be used for soft tissue ablation, in fact soft tissue also contains a high percentage of water.

 

Fig. 8

Diode Laser

The active medium of the diode laser is a solid state semiconductor made of aluminum, gallium, arsenide, and occasionally indium. All diode wavelengths are primarily absorbed primarily by tissue pigment (melanin) and hemoglobin. These are poorly absorbed by the hydroxyapatite and water present in the enamel. Specific procedures that can be carried out with these wavelengths include , treatment of dentinal hypersensitivity, gingivectomy, frenectomies, it is a big help in all the impressions , traditional and-or optical.

 

Fig. 9

Technical considerations

Lasers are light! A laser beam can interact differently with tissues: it can be totally absorbed, reflected, deflected or transmitted.
By selecting the correct power and wavelength we can hit a target through another tissue: this ability is used in many medical surgery techniques.

However, these can easily create eye damage if not adequately protected

Fig. 10

Protecting your eyes is of utmost importance, just as protecting those of your patient and your assistant. Lasers can damage in different – but always severe –ways your eyes!

All the lasers have a specific filter dedicated to their specific wavelength, so don’t mix them!

Fig. 11

We can have also specific eye protectors for our patient.

Fig. 12

Specific action on the retina.

Fig. 13

Specific action on the cornea.

 

 

LASER DIAGNOSTICS

Diode lasers can be really helpful in caries diagnosis and actually increase the sensibility and specificity of our diagnostic process.

Fig. 14

DIAGNODENT PEN

Diagnodent pen gives numbers using te principle of laser fluorescence. It is really useful in sulcular caries of the occlusal surface. It is able to detect bacteria because of its specific fluorescence, higher than the healthy tooth.

The result of the examination are numbers, to decide treatment plan:

12 > healty 

13 < monitor <25

25 < caries

A progressive sound signal beep is helpful to share the process with your patient during the examination: when the laser beam reaches bacteria, the beep goes to a higher volume. It unfortunately does’t provide images.

Fig. 15

DIAGNOCAM

Near infrared light is able to see through enamel and dentine, both in occlusal and inter proximal areas, and provides images to detect, measure and record. The feature that I love the most, is that showing images to the patient is really effective! Today, I think this tool is something we really need to find caries, to build treatment strategies and trust by our patients: being understandable is hard, so the diagnostic process just put in front of us and our patient is a gift to both.

 

Conclusions

The two more used lasers are Diode and Erbium; your choice should depend on what you are wishing to accomplish with a laser, aka, which is your target.

hard tissue – ERBIUM                              soft tissue – DIODE

In the decision making process, of course the price is a relevant factor (Erbium lasers are almost 10x more expensive than Diode lasers). This said, what I really think is that today laser cannot be thought of as future… it’s part of this exciting present time. A really useful instrument for our daily work: 

“If you could use it for just one single day, I’m 100% sure you’d be crazy mad to me taking it away from you.”

 

Bibliography

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Low SB, Mott A. Laser technology to manage periodontal disease: a valid concept? J Evid Based Dent Pract. 2014 Jun;14 Suppl:154-9.

Sgolastra F, Petrucci A, Severino M, Gatto R, Monaco A. Lasers for the treatment of dentin hypersensitivity: a meta-analysis. J Dent Res. 2013 Jun;92(6):492-9.

Marisa Roncati. Nonsurgical periodontal therapy. Quintessence, 2017.

Wigdor HA, Walsh JT Jr, Featherstone JD, Visuri SR, Fried D, Waldvogel JL. Lasers in dentistry. Lasers Surg Med. 1995;16(2):103-33.

Robert A. Convissar. Principles and Practice of Laser Dentistry. Edited by Mosby Elsevier. 2010.

Zandaparsa R. Latest biomaterials and technology in dentistry. Dent Clin North Am 2014 Jan;58(1):113-34.