LASERS USED IN DENTISTRY
Laser nomenclature depends on its active medium, the wavelength, the transmission system, the oscillation mode, tissue absorption and clinical applications.
The argon lasers have two wavelength: 488 nm (blue) and 514 nm (blue-green).Argon laser at 488 nm wavelength is widely used in composite resin applications, tooth whitening and decay protection works. 514 nm wavelength has peak absorption at red pigment.Tissues containing hemoglobin, hemosiderin and melanin interacts with this laser.It is a useful surgical laser with excellent hemostatic capabilities.It is suitable to be used in contact with the tissue for the treatment of acute inflammatory periodontal disease and highly vascularized lesions such as hemangiomas.Both the wavelength is used for the determination of caries.When the argon laser light enlightens the caries, they are seen in dark orange red color and it is easily distinguishable from the surrounding healthy structures.
Its wavelength is between 800-980 nm.Each machine delivers the laser energy through optical fiber means with continuous-wave intermittent-pulse mode and it is generally in contact with the tissue.These lasers can be used safely for soft tissue surgery in a way close to the enamel, dentin and cementum.Diode is an excellent soft tissue surgical laser designed for gingival and mucosal segmentation, coagulation and soft tissue curettage or for sulcus cleaning.Semiconductor diode laser: 30mW Ga1As semiconductor laser device was developed to avoid sensitivity.After drying potential hypersensitive dentin, the laser is used in direct contact with the surface of the periodically irradiated teeth from 30 seconds to 3 minutes.
Carbon dioxide (CO2) Laser
Its wavelength is 10600 nm.It is very well absorbed by the water.It is used in quick soft tissue removal and it has a low-deep penetration into the tissue.It is especially useful in dense fibrotic tissue sections.It is stated that it has strong hemostatic and bactericidal effects and creates minimal scar tissue.The strongest hemostasis is performed with a CO2 laser, however, it has the slowest healing.While its fast and non-bleeding operation makes CO2 laser an appropriate choice for soft tissue surgery, which has single indication, the use in the hard tissues neighborhood should be performed under very detailed control such as microscope magnification as it can create carbonization even in the short interactions with the hard tissue.
It is the first produced laser system and the first started to be used in dentistry.It is usually used for section and coagulation of soft dental tissues with good hemostatic properties.This laser can be used for major pathological sterilization and occluding.Although Nd:YAG lasers are initially used for excision of large pathological cases, with the development of optical fiber cable transmission systems with direct contacts, not only sectioning, but also sterilization and covering operations have become possible to be performed at very low powers.Nd: YAG laser can be performed in gingivoplasty, gingivectomy, removal of prosthesis-induced hyperplasia, reducing gingival hypertrophy, the opening of the implant cover, opening of the cover of the unerupted tooth, crown lengthening through soft tissue operations, curettage, abscess incision and drainage, excisional and incisional biopsies, removal of postoperative granulation tissue, frenectomy, endodontia, removal of canal sealing materials such as resin or gutta-percha, treatment of cervical sensitivity.
Its wavelength is 2120 nm.Ho laser is usually used for arthroscopic surgery of the temporomandibular joint.
Er: YAG Laser (Erbium-doped:Yttrium, Aluminium and Garnet)
Its wavelength is 2940 nm.It is the laser which is best absorbed in water.The sections performed with the erbium laser shows the fastest healing than almost all surgical methods.The main reason for this is that the laser causes very little thermal damage to the soft tissue.The advantage of this laser is its being able to treat the carious lesion which is very close to gingiva for restorative dentistry and its ability to reposition the soft tissue with the same instrument.Er: YAG laser can be used in cavity preparation, direct pulp capping, roughening the enamel, fissure sealants, removing the sealing materials (Composite resin, glass ionomer cement ... etc), treatment of cervical sensitivity, gingivectomy, intra-oral soft tissue surgery, apical resection surgery, endodontic cavity preparation, cleaning of the root canal, the preparation of the root canal through expansion, extirpation of the pulp, pulp amputation.
Er,Cr: YSGG Laser (Erbium, Chromium-doped:Yttrium, Scandium, Gallium and Garnet)
Its wavelength is 2780 nm and it is a laser type used only in hard tissues.