By Leslie Canham, CDA, RDA
Lasers in dentistry are becoming more popular. The term “laser” is an acronym for Light Activated by Stimulated Emission of Radiation. A laser beam is a highly concentrated beam of light. Lasers can be used to detect caries, prepare teeth for fillings, seal dental tubules to reduce sensitivity, and whiten teeth. There are also soft-tissue applications as the beam can be adjusted to enable it to cut, vaporize, or cauterize tissue.
There are several different types of dental lasers. These include DIAGNOdent, diodes, Neodymium-Yttrium-Aluminum-Garnet or Nd:YAG, erbium, and carbon dioxide or CO2.
The DIAGNOdent is a type of fluorescence laser used for caries detention. It is considered a Class 1 laser. The wavelength of this type of laser is 655 nanometers (nm). Nanometers are measurements of units — one nanometer is one billionth of a meter. Protective eyewear for dental health-care providers and patients does not need to be filtered to protect from the DIAGNOdent beam; however, dental health-care providers should always don protective eyewear for protection against splashes or spatter of chemicals, blood, saliva, or any potentially infectious materials.
With a variety of lasers are a variety of wavelengths. Diode lasers are used for soft tissue. The wavelength for diode lasers varies from 810 nm to 1064 nm. Nd:YAG lasers are used for soft tissue and have a wavelength of 1064 nm. Erbium lasers are used for both hard and soft tissue and have a wavelength of 2780 nm to 2940 nm. CO2 lasers are used for soft tissue and have a wavelength of 10600 nm.
Diodes, Nd:YAG, erbium, and CO2 lasers are Class 4 lasers, which are considered high-powered dental lasers. They are a hazard to eyes and skin and require special precautions. Specially filtered protective eyewear must be worn to protect dental health-care providers and patients from the beam.
The Food and Drug Administration regulates lasers as medical devices. The FDA requires engineering controls for laser use. Engineering controls include an on/off key or password to operate the unit, an emergency stop button, a foot switch cover guard, safety interlocks on paneling and housing, software diagnostics, standby mode prior to ready mode with a five-second delay, system time out, and visible and auditory sounds when the laser is in use.
The American National Standards Institute (ANSI) recommends that there be administrative controls for laser use. Administrative controls include that there be a laser safety officer responsible for making sure all engineering controls are in place. Another responsibility of the laser safety officer is determining the hazard zone for each laser. The hazard zone is the distance around the laser that is dangerous when the laser is in use. This distance is device-specific and not wavelength-specific, so it is important to review and understand the manufacturer’s instructions for each type of laser used in the dental practice to determine the hazard zone. A “Laser in Use” sign must be posted outside the operatory when a laser is being used.
Another responsibility of the laser safety officer is to make sure that appropriate protective eyewear is available. Eyewear is laser-specific, determined by the wavelength. One kind of specially filtered eyewear for a brand/type of laser may not be enough protection for another brand/type of laser. The eyewear itself will display the optical density (OD) and the nanometers that it protects against. Health-care providers should carefully review the laser device owner’s manual and operating instructions to confirm that the eyewear is the appropriate level of protection for the device being used. Protective eyewear should be cleaned with soap and water and dried with a scratch-free soft cloth. Harsh disinfectants are not recommended because they may remove the thin protective film on the lens. Be careful not to scratch the lens. Laser eyewear is costly, and if it is scratched it cannot be used again.
It is important to understand basic principles of dental lasers to prevent damage to the eyes. Closing eyes or turning the head away from the laser does not protect from the beam. Also the laser can bounce off of reflective surfaces in the treatment room, such as mirrors, Plexiglass, and even the glass from a picture on the wall. Anyone who operates a laser or assists during laser use must be well versed in the use of lasers and follow all safety precautions.
Guidelines for laser safety
- Shielded eyeglasses — The dental team, patient, and others in the treatment room must wear special shielded eyeglasses to protect the eyes.
- Matte-finished instruments — Reflective surfaces such as instruments, mirrors, and even polished restorations can reflect laser energy. Matte-finished (nonshiny) instruments are recommended to avoid this reflection.
- High-volume evacuation — HVE should be used to draw off the plume (cloud) created when tissue vaporizes. This plume is aerosolized and could be infectious.1 Therefore, a high-filtration-rate protective mask (0.1 micron) is recommended for use with dental lasers.
Author bio
Leslie Canham is a dental speaker and consultant specializing in infection control and OSHA compliance. She has more than 36 years of experience in dentistry. Canham is the founder of Leslie Canham Seminars, providing in-office training, mock inspections, consulting, and online seminars and webinars to help the dental team navigate state and federal regulations. Reach Canham at (888) 853-7543 or Leslie Canham.
References
1. Bird DL, Robinson DS. Modern Dental Assisting. 8th ed. St. Louis, MO: Elservier Saunders.
