A dental laser is a type of

laser A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word ''laser'' originated as an acronym for light amplification by stimulated emission of radi ...

designed specifically for use in

oral surgery Oral and maxillofacial surgery (OMFS) is a surgical specialty focusing on reconstructive surgery of the face, facial trauma surgery, the mouth, head and neck, and jaws, as well as facial plastic surgery including cleft lip and cleft palate ...

dentistry Dentistry, also known as dental medicine and oral medicine, is the branch of medicine focused on the Human tooth, teeth, gums, and Human mouth, mouth. It consists of the study, diagnosis, prevention, management, and treatment of diseases, dis ...

. In the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

, the use of lasers on the

gums The gums or gingiva (: gingivae) consist of the mucosal tissue that lies over the mandible and maxilla inside the mouth. Gum health and disease can have an effect on general health. Structure The gums are part of the soft tissue lining of the ...

was first approved by the

Food and Drug Administration The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respo ...

in the early 1990s, and use on hard tissue like

teeth A tooth (: teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tear ...

or the bone of the

mandible In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...

gained approval in 1996. Several variants of dental lasers are in use with different

wavelength In physics and mathematics, wavelength or spatial period of a wave or periodic function is the distance over which the wave's shape repeats. In other words, it is the distance between consecutive corresponding points of the same ''phase (waves ...

s and these mean they are better suited for different applications.

Soft tissue lasers

* Diode lasers *

Carbon dioxide laser The carbon-dioxide laser (CO2 laser) was one of the earliest gas lasers to be developed. It was invented by C. Kumar N. Patel, Kumar Patel of Bell Labs in 1964 and is still one of the most useful types of laser. Carbon dioxide, Carbon-dioxide lase ...

s * Nd:YAG laser Diode lasers wavelengths in the 810–1,100 nm range are poorly absorbed by the soft tissues such as the

gingiva The gums or gingiva (: gingivae) consist of the mucosal tissue that lies over the mandible and maxilla inside the mouth. Gum health and disease can have an effect on general health. Structure The gums are part of the soft tissue lining of the ...

e, and cannot be used for soft tissue cutting or ablation. Instead, the distal end of diode's glass fiber is charred (by burned ink or by burned corkwood, etc.) and the char is heated by the 810-1,100 nm laser beam, which in turn heats up the glass fiber's tip. The soft tissue is cut, on contact, by the hot charred glass tip and not by the laser beam itself. This is used for variety of oral surgery procedures such as gingivectomy, frenectomy, treatment of pericoronitis, and exposure of superficially impacted teeth. This method was primarily used by the Michigan school of dentistry . Similarly Nd:YAG lasers are used for soft tissue surgeries in the

oral cavity A mouth also referred to as the oral is the body orifice through which many animals ingest food and vocalize. The body cavity immediately behind the mouth opening, known as the oral cavity (or in Latin), is also the first part of the alime ...

, such as gingivectomy, periodontal sulcular debridement, LANAP, frenectomy,

biopsy A biopsy is a medical test commonly performed by a surgeon, interventional radiologist, an interventional radiologist, or an interventional cardiology, interventional cardiologist. The process involves the extraction of sampling (medicine), sample ...

, and

coagulation Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a thrombus, blood clot. It results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The process of co ...

of graft donor sites. The Nd:YAG laser wavelength are partially absorbed by pigment in the tissue such as hemoglobin and melanin. These lasers are often used for debridement and disinfection of periodontal pockets. Their coagulative ability to form fibrin allows them to seal treated pockets. The CO₂ laser remains the best surgical laser for the soft tissue where both cutting and

hemostasis In biology, hemostasis or haemostasis is a process to prevent and stop bleeding, meaning to keep blood within a damaged blood vessel (the opposite of hemostasis is hemorrhage). It is the first stage of wound healing. Hemostasis involves three ...

is achieved photo-thermally (radiantly).

Soft and hard tissue lasers

* Er:YAG laser *

* Er,Cr:YSGG laser Erbium lasers are both hard and soft tissue capable. They can be used for a host of dental procedures, and allow for more procedures to be done without local anaesthesia. Erbium lasers can be used for hard tissue procedures like bone cutting and create minimal thermal and mechanical trauma to adjacent tissues. These hard tissue procedures show an excellent healing response. Soft tissue applications with erbium lasers feature less hemostasis and coagulation abilities relative to the CO₂ lasers. laser was found to be effective in gum de-pigmentation. The new CO₂ laser operating at 9,300 nm features strong absorption in both soft and hard tissue and is the newest alternative to erbium lasers. The 9,300 nm laser ablates hard tissue in excess of 5,000 °C, which often results in extremely bright thermal radiation.

Dental caries removal

In September 2016, the Cochrane collaboration published a

systematic review A systematic review is a scholarly synthesis of the evidence on a clearly presented topic using critical methods to identify, define and assess research on the topic. A systematic review extracts and interprets data from published studies on ...

of the current evidence comparing the use of lasers for

caries Tooth decay, also known as caries,The word 'caries' is a mass noun, and is not a plural of 'carie'.'' is the breakdown of teeth due to acids produced by bacteria. The resulting cavities may be a number of different colors, from yellow to black ...

removal, in both

deciduous In the fields of horticulture and botany, the term deciduous () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed Leaf, leaves, usually in the autumn; to the shedding of petals, aft ...

and adult teeth, with the standard dental drill. The authors reviewed nine trials published between 1998 and 2014, with 662 participants in total. These included three different types of laser: Er:YAG; Er,Cr:YSGG; and Nd:YAG. Overall, the quality of the evidence available was found to be low, and the authors were unable to recommend one method of caries removal over the other. There was no evidence of a difference between the marginal integrity or durability of the restorations placed. However, there was some evidence that the laser produced less pain and required less anesthesia than the drill. The authors concluded that more research is required.

Cost of lasers

Use of the dental laser remains limited, with cost and effectiveness being the primary barriers. The cost of a dental laser ranges from $4,000 to $130,000, where a pneumatic

dental drill A dental drill or dental handpiece is a hand-held, mechanical instrument used to perform a variety of common dentistry, dental procedures, including removing tooth decay, decay, polishing dental filling, fillings, performing cosmetic dentistry, a ...

costs between $200 and $500. Hard tissue lasers are incapable of performing some routine operations in the treatment of cavities.

Benefits of lasers

Dental lasers are not without their benefits, though, as the use of a laser can decrease

morbidity A disease is a particular abnormal condition that adversely affects the structure or function of all or part of an organism and is not immediately due to any external injury. Diseases are often known to be medical conditions that are asso ...

after surgery, and reduces the need for anesthetics. Because of the

cauterisation Cauterization (or cauterisation, or cautery) is a medical practice or technique of burning a part of a body to remove or close off a part of it. It destroys some tissue in an attempt to mitigate bleeding and damage, remove an undesired growth, or ...

of tissue there will be little bleeding following soft tissue procedures, and some of the risks of alternative electrosurgery procedures are avoided. Additionally, the use of dental lasers is associated with less vibration and a more favorable noise profile when compared to pneumatic dental drills.

History

Kumar Patel made the first CO₂ laser in 1964, in the same year the Nd:YAG Laser was invented at

Bell Labs Nokia Bell Labs, commonly referred to as ''Bell Labs'', is an American industrial research and development company owned by Finnish technology company Nokia. With headquarters located in Murray Hill, New Jersey, Murray Hill, New Jersey, the compa ...

.{{Cite web , url=http://www.kigre.com/files/historylasers.pdf , title=A brief history of lasers , access-date=2014-06-16 , archive-url=https://web.archive.org/web/20140611181322/http://www.kigre.com/files/historylasers.pdf , archive-date=2014-06-11 , url-status=dead

References

Dental equipment