“In times of change, it is the ‘learners’ who will inherit the earth; while the ‘learned’ will find themselves beautifully equipped for a world that no longer exists” Al Rogers
Born: Dec. 3, 1919. Died: May 22, 2011
LASERS in Dentistry
We're going to learn about lasers today! Everyone who has seen the movie Star Wars has an idea of what a laser is… we have Einstein to thank for the theory behind its creation, but how does it function & what are its applications in modern medicine?
There are two main types that we use to describe dental lasers:
- Soft Tissue
- Hard Tissue
I would like you to understand the types of lasers out there, the parameters they operate within and the physics of their wavelength. We will also review the safety and the applications for lasers in dentistry. The following is a summary from groups of others work:
Laser stands for Light Amplification by the Stimulated Emission of Radiation. Lasers work by producing an intense beam of bright light that travels in one direction. The laser has the unique ability to produce one specific color or wavelength of light, which can be varied in its intensity and pulse duration. The newest laser systems have become remarkably precise and selective, allowing treatment results and safety levels not previously available. All lasers contain an energized substance that can increase the intensity of light that passes through it. This substance is called the amplifying medium and it can be a solid, a liquid or a gas. Einstein can be considered as the father of the laser. 80 years ago he postulated photons and stimulated emission and won the Nobel Prize for related research on the photoelectric effect.
CHARACTERISTICS OF LASER RADIATION
Monochromatic = very precise color or wavelength
Collimated = very directional can be focused
Coherent = synchronized in phase
The higher the frequency (the bluer the color), the greater the energy carried by that bundle. So, in effect… Darth Vader's red light saber (laser) is actually weaker than the green and blue ones the jedi use!! On another side note, Einstein's Nobel Prize was not awarded for either one of his relativity theories – the Nobel Committee thought them too speculative at the time. Rather Einstein won the prize for explaining the photoelectric effect. Two of Einstein's 1905 papers were on the theory of atoms and molecules, yet there were still many scientists in 1905 who did not believe in atoms or molecules.
There are many lasers such as the carbon dioxide laser or CO2 laser, and many forms of this too. In contrast to the old carbon dioxide lasers, the newest generation of the CO2 laser delivers short bursts of extremely high-energy laser light. In a erbium-doped YAG (Er:YAG) laser, the amplifying medium is a rod of yttrium aluminum garnate (YAG) containing neodymium ions. In a dye laser, it is a solution of a fluorescent dye in a solvent such as methanol. In a helium-neon laser, it is a mixture of the gases helium and neon. In a Diode laser, it is a thin layer of semiconductor material sandwiched between other semiconductor layers.
The factor by which the intensity of the light is increased by the amplifying medium is known as the gain. The gain is not a constant for a particular type of medium. It depends critically upon the wavelength of the incoming light, the length of the amplifying medium and also upon the extent to which the amplifying medium has been energized. In order to increase the intensity of the light, we would need to energize the amplifying medium, or in other terms, pumping.
There are several ways of pumping an amplifying medium. When the amplifying medium is a solid, pumping is usually achieved by irradiating it with intense light. This light is absorbed by atoms or ions within the medium and raises them into higher energy states. Often, the pumping light comes from xenon-filled flash tubes that are positioned alongside the amplifying medium.
The laser has been used in the medical field as well. This revolutionary technology actually vaporizes the undesired skin tissue, one layer at a time, revealing fresh skin underneath. The CO2 laser’s highly focused aim enables the dermatological surgeon to gently remove the skin’s surface with a low risk of scarring and complications in properly selected patients. The laser beam can gently vaporize and remove wrinkles, scars and blemishes, seal blood vessels or cut skin tissue.
Different Lasers are absorbed at varying rates into specific tissue types. For dentistry we like to focus on the two primary players in our industry:
1. Waterlase ErYAG operates at 2780 Nm and target
Water and Hydroxyapatite (Enamel)
2. Diode Lasers 810Nm target
Melanin and Hemoglobin
- Electromagnetic spectrum: near infrared, invisible
- Delivery System: optic fiber
Wavelength measured in nanometers.
Nanometer = 10 -9 meters = smaller than a virus
Are low level lasers SAFE?
Laser diodes have been used for years in such applications as bar code check outs, CD players, laser printers and pointers. The FDA has listed bio-stimulation lasers as non- significant risk (NSR) devices.
Cold lasers are extremely safe because the laser light/radiation has no effect on healthy cells. Yet, worldwide research, tests and studies have shown conclusively that cold laser light restores balance, energy and nutrient, oxygen permeability to sick cells. Thus resulting in excelerated healing and regeneration. This healing is additionally supported by the lasers ability to cause key enzymes and hormones to be secreted, which reduces or elliminates inflammation and pain.
Have low level lasers been scientifically studied and proven?
Low level lasers have been used world-wide for over 50 years. Over 2000 studies have shown that low level lasers:
(1) REDUCE PAIN by stimulating cells to produce their own endorphins, natural pain killers, (2) PROMOTE FASTER HEALING by stimulating cells to increase the production of two major healing enzymes by as much as 75%, (3) REDUCE INFLAMMATION by as much as 75%, (4) INCREASE BONE REPAIR SPEED by stimulating fibroblastic and osteoblastic proliferation, (5) RELAX MUSCLES and muscle spasms, (6) DECREASE SWELLING by stimulating lymphatic drainage, (7) ENHANCE THE IMMUNE SYSTEM by increasing the number of "killer" cells by 400- 900%, and most importantly, (8) RE-ENERGIZE CELL MEMBRANES to allow transport of essential nutrients across cell walls (nutrients will not cross an injured or sick cell wall, thus slowing healing) allowing a healthy new cell to grow.
- Power (energy) density (watts per centimeter squared)
- Radiation Wavelength
- Operation Mode (PULSE or Continuous)
LASERS in MEDICINE
Tissue effects are a result of all of the following factors.
- Power Density
- Duration of Exposure
- Specific Wavelength
- Emission Mode (pulses)
- Tissue Chararcteristics (deep pigmentation takes less energy / absorbs)
Most importantly are the
= IRRADIATION VOLUME
WATERLASE= Biolase YAG: This is a patented interaction of water and laser as YSGG Laser HydroPhotonics. Advanced capabilities and new features coupled with innovative, ergonomic styling and design, are part of our proprietary technology platform. In February 2009, we introduced the Waterlase MD Turbotm All-Tissue Dental Laser System with cutting speeds approaching that of a high speed drill.
Laser Hard Tissue Applications
Hard Tissue Procedures
Class I, II, III, IV and V cavity preparation
Hard tissue surface roughening or etching
Enameloplasty, excavation of pits and fissures for placement of sealants
Laser Cosmetic Procedures
Bone Surgical Procedures
Cutting, shaving, contouring and resection of osseous tissues (bone)
Root Canal/Endodontic Procedures
The WaterLase MD™ with Endolase™ Radial Firing Tips is indicated for disinfection of the root canal after endodontic instrumentation.
Tooth preparation to obtain access to root canal
Root canal preparation including enlargement
Root canal debridement and cleaning
Flap preparation – incision of soft tissue to prepare a flap and expose the bone Cutting bone to prepare a window access to the apex (apices) of the roots
Root end preparation for retrofill
Removal of pathological tissues and hyperplastic tissue
Laser Soft Tissue Applications I
Soft Tissue Procedures Including Pulpal Tissues
Excisional and incisional biopsies
Exposure of unerupted teeth
Frenectomy and frenotomy
Gingival troughing for crown impressions
Gingival incision and excision
Flap preparation – incision of soft tissue to prepare a flap and expose the bone
Flap preparation – incision of soft tissue to prepare a flap and expose unerupted teeth (hard and soft tissue impactions)
Laser Soft Tissue Applications II
Incision and drainage of abscesses
Pulpotomy as an adjunct to root canal therapy
Root canal debridement and cleaning
Reduction of gingival hypertrophy
Soft tissue crown lengthening
Sulcular debridement (removal of diseased and inflamed soft tissues)
Laser soft tissue curettage of the post-extraction tooth sockets and the periapical area during apical surgery
Treatment of canker sores, herpetic and aphthous ulcers of the oral mucosa. These uses are GREAT for patients and often you don't even think of the dentist office as a place to treat things like this:
Laser Periodontal Therapy
Laser Periodontal Procedures
Full thickness flap Partial thickness flap
Split thickness flap Laser soft tissue curettage
Laser removal of diseased, infected, inflamed and necrosed soft tissue within the periodontal pocket
Removal of highly inflamed edematous tissue affected by bacteria penetration of the pocket lining and junctional epithelium
Removal of granulation tissue from bony defects
Sulcular debridement (removal of diseased or inflamed soft tissue in the periodontal pocket to improve clinical indices including gingival index, gingival bleeding index, probe depth, attachment loss and tooth mobility)
Osteoplasty and osseous recontouring (removal of bone to correct osseous defects and create physiologic osseous contours)
Ostectomy (resection of bone to restore bony architecture, resection of bone for grafting, etc.)
Osseous crown lengthening