Year : 2016 | Volume
: 7 | Issue : 3 | Page : 112--114
Dental lasers: A review of safety essentials
Subbaiah Pradeep1, SR Anitha2, S Ravi1, BM Shivalinga1, H Jyothikiran1,
1 Department of Orthodontics and Dentofacial Orthopaedics, JSS Dental College and Hospital, Mysore, Karnataka, India
2 Department of Pedodontics, CODS, Davangere, Karnataka, India
Department of Orthodontics and Dentofacial Orthopaedics, JSS Dental College and Hospital, Mysore, Karnataka
Dental professionals are predisposed to a number of occupational hazards. These include exposure to ionizing radiation and nonionizing radiation. The current paper reviews the studies relating to occupational health problems in dental practice.
|How to cite this article:|
Pradeep S, Anitha S R, Ravi S, Shivalinga B M, Jyothikiran H. Dental lasers: A review of safety essentials.Int J Orthod Rehabil 2016;7:112-114
|How to cite this URL:|
Pradeep S, Anitha S R, Ravi S, Shivalinga B M, Jyothikiran H. Dental lasers: A review of safety essentials. Int J Orthod Rehabil [serial online] 2016 [cited 2019 Dec 5 ];7:112-114
Available from: http://www.orthodrehab.org/text.asp?2016/7/3/112/192535
The safe and appropriate use of lasers in the field of dentistry requires the conscious and cooperative efforts of health-care providers, educational institutions, government, and commercial sector. The responsibility for the safe application of lasers in dentistry, therefore, is one that is shared by all those concerned namely dentist, academician, manufacturers, and scientist. Each has a specific role, from design and development to practical application. 
Dental laser safety includes not only an awareness of the potential risks and hazards related to how lasers are used but also the recognition of existing standards of care and a thorough understanding of safety control measures.
Laser hazard classification according to the ANSI and UHSA standards. 
The types of hazards that may be encountered within the clinical practice of dentistry may be grouped as follows: 
Ocular injuryTissue damageRespiratory hazardsFire and explosionElectrical shock.
Precautions for dental staff and patients are essential during laser procedures to protect nontarget tissues particularly the eyes from stray beams.  Potential injury to the eye can occur either by direct emission from the laser or by reflection from specular (mirror-like) surface, instruments, and even polished restorations have potential to redirect laser energy. 
Several structures of the eye may be injured as a result of laser emissions. The primary ocular injury that may result from a laser accident is a retinal or corneal burn. The retinal injury is possible with emissions in the visible and near-infrared spectral regions. 
Approximately, 95% of the incident radiation entering the eye is absorbed by pigmented epithelium of the retina and choroid layer - irreversible retinal burns resulting in permanent blindness can occur by the conversion of incident radiation to heat energy within a fraction of a second. 
The safe use of the laser requires certain special precautions in the operating theater. The light produced by all Class IV lasers presents a potential hazard for ocular damage by either viewing or reflection of the beam. Therefore, serious consideration must be given to the need for protective eyewear. Different lasers require different safety glasses. ,,
A number of factors must be considered when prescribing suitable protective eyewear. These include the wavelengths or wavelengths emitted by the laser, the level of attention necessary to reduce the incident beam to less than the maximum permissible exposure and the extent to which the eyewear reduces the transmission of visible light, possibility of damage of the lense material by the laser beam and the comfort with which the eyewear can be worn.  The wearing of the wrong goggles is more dangerous than not wearing any at all.
Matte instruments are advisable, as are protective eyeglasses for patients and staff. CO 2 laser protection can be provided with clear safety glasses, such as those that are normally worn during dental procedures. Clear safety glasses are worn by the patient as well, and as a backup measure, wet 2 ×2 gauze sponges are placed over the patient's eyes. For protection from neodymium-doped : yttrium aluminium (Nd:YAG) laser energy, both the doctor and staff need to wear green safety glasses and for protection; from the argon laser, orange safety glasses are required. One safety glass cannot be interchanged for the other, one should not wear clear safety glasses when using the Nd:YAG or argon laser nor green safety glasses when using the CO 2 laser. 
Instruments that are highly reflective or that have mirrored surfaces should be avoided as there could be reflection of the laser beam. 
High-powered carbon dioxide lasers produce light with sufficient energy to burn tissue. Heat measured from reflected surgical laser exposure exceeds 53° at a distance <7 cm and thus is hazardous to the patient and operator. This problem can be controlled with the use of nonreflective instruments. 
Neiburger et al.  measure the intensity of reflected 10 W CO 2 light and its thermal effects on adjacent structures and concluded that reflected CO 2 laser light (10 W) was a hazard to oral and surrounding tissues at distances up to 7.0 cm from the focal point and advised the use of low reflective instruments and protective shielding during laser treatment.
General anesthesia is commonly used for intraoral laser surgery, and this introduces hazards associated with the anesthetic gases and the endotracheal tube. The thermal effects of CO 2 laser can cause the combustion of inflammable gases. The tube may ignite if it is plastic and may melt if it is rubber. This can be avoided using a specifically designed endotracheal tube made of metal or covered with laser-resistant silicone.
The laser plume created when tissue vaporizes should be considered infectious. The use of an appropriate evacuation system to draw off and filter the plume is essential. 
Surgical lasers often use very high currents and high voltage power supplies. Electrical hazards of lasers can be grouped as electric shock hazards, electric fire hazards, or explosion hazards. Considerable effort has been made by biomedical and electrical engineers in the design and manufacture of safe laser systems. Insulated circuitry, shielding, grounding, and housing of high-voltage electrical components provide adequate protection under most circumstances from electrical injury. 
The laser plume, which is the smoke or vapor emitted from the site of surgery during exposure to laser energy, is a special concern. Tomita et al., in 1981, demonstrated that CO 2 laser smoke had harmful effects on the respiratory system in animal models. 
Airborne contaminants may be controlled by ventilation, evacuation, or other methods of respiratory protection. Laser surgery within the oral cavity or near respiratory passages requires sufficient evacuation of the plume for patient protection. 
Above all, personnel operating the laser or attending laser procedures must be thoroughly trained to respect this powerful tool and follow standard protocols. 
The unique versatility and vast potential of dental lasers allow many procedures that enhance overall treatment success Thus, lasers have become an indispensable clinical tool in a dental armamentarium. Proper safety measures as to be taken by the clinicians in dental practice.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
|1||Miserendino LJ, Pick RM. Laser in Dentistry. Chicago: Quintessence Publishing; 1995.|
|2||Powel GL. Lasers in the limelight. JADA 1992;123:71-4.|
|3||Pick RM, Powell GL. Laser in dentistry. Soft-tissue procedures. Dent Clin North Am 1993;37:281-96.|
|4||Strang R, Moseley H, Carmichael A. Soft lasers - Have they a place in dentistry? Br Dent J 1988;165:221-5.|
|5||Neiburger EJ, Miserendino L. Laser reflectance: Hazard in the dental operatory. Oral surg 1988;66:659-61.|
|6||Miller M, Truhe T. Lasers in dentistry: An overview. JADA 1993;122:51-3.|