By –Dr. Shanin Farista
Since the development of the Ruby Laser by Maiman in 1960 and introduction of its application in Endodontics by Weichmann in 1971, there is the constant rise in research works in the field of endodontics, an urge to explore the implications of the different applications. Now it is well established that Lasers offer worthy advantages not only to providers but also to the beneficiaries. All the wavelengths available for the dental use has some of the other application in the field of endodontics but to be specific most commonly used dental laser for Endodontics are the Erbium and the Diode Lasers. This blog offers an overview of Lasers In Endodontics.
The chief objective of endodontic treatment is effective cleaning of the root canal system. But there are some limitations of the conventional endodontic therapy such as cleaning of lateral canals, some anatomical complexities, and the apical ramifications. Laser technology was introduced in endodontics with the goal of improving the results so obtained with traditional procedures by increasing cleaning ability, removing smear layer from the root canals and also improving the decontamination of the endodontic system at the same time.
Laser in Access Cavity Preparation
The preparation of the access cavity can be performed directly with Erbium lasers, which can ablate enamel and dentine. The laser allows for minimally invasive access into the pulp chamber owing to its affinity to tissues richest in water (pulp and carious tissue) and at the same time, allows for the decontamination and removal of bacterial debris and pulp tissue. Moreover, Erbium lasers are very useful in the removal of pulp stones and in cases of calcified canals.
Laser in Cleaning and Shaping of Root Canals
The preparation of the canals with NiTi instruments are still considered as gold standard in endodontics. However, the Erbium,Chromium:YSGG (Er,Cr:YSGG) and the Erbium: YAG (Er: YAG) lasers have received FDA approval for cleaning, shaping and enlarging canals but still the acceptance of their effectiveness in the preparation of root canals appears to be limited at the moment. Lasers have a good capability for enlarging and shaping in a faster and improved manner compared with the traditional method. Olivi G in 2011 shared that the SEM observations demonstrates a uniformly cleaned dentinal surface with absence of pulp tissue.
Disinfection of the Endodontic System
When the laser-assisted canal decontamination is performed with Near Infrared Laser (Diode – 810nm, 940nm or 980nm), it requires the preparation of canals in the traditional way (apical preparation with ISO 25/30) because these wavelength has no affinity for hard tissue and therefore they have no use in preparing or shaping the canals. The irradiation is done at the end of the traditional endodontic preparation as a final means of disinfecting the endodontic system before obturation. Literature states that they bring about a more or less absolute reduction of the bacterial load (99.9 % of E. faecalis) from the root canals.
When the Mid Infrared Laser (Erbium – 2780nm or 2940nm) is only used for laser-assisted canal decontamination, the canals need to be prepared in the traditional way (apical preparation with ISO 25/30). The thermal energy so created by these lasers are absorbed on the tooth surface exhibiting the highest bactericidal effect on E. coli (Gram-negative bacteria), and E. faecalis (Gram-positive bacteria). Erbium lasers have shown to remove bacterial biofilm from the apical third having numerous bacterial species (e.g. A. naeslundii, E. faecalis, L. casei, P. acnes, F. nucleatum, P. gingivalis or P. nigrescens etc).
Irrigants Activation (LAI) and Removal of Smear Layer
The ability of lasers to activate the irrigating liquid inside the root canal to increase its action was first published by George. The photomicrographic studies suggests that the laser generates a movement of fluids at high speed through a cavitation effect. The expansion and successive implosion of irrigants generates a secondary cavitation effect on the intra-canal fluids. Some researches stated that it is sufficient to keep the laser tip in the middle third some 4-5mm away from the apex and not necessarily reach the apex and negotiate radicular curves. With high level magnification, the collagen structure of the root dentine seems to remain intact, supporting the hypothesis of a minimally invasive endodontic treatment with lasers.
Having known about the uses and advantages of lasers in every step of endodontic therapy, it can be said that lasers are recommended for all endodontic treatments but it is most valuable in the following clinical situations:
- Infected cases with apical, lateral and/or furcal radiolucencies;
- Retreatments with peri-apical periodontitis;
- Acutely inflamed cases, especially those diagnosed with Cracked Tooth Syndrome;
- Internal and external resorption;
- Persistent infections not responding to conventional endodontic treatment; and
- Unexplained, prolonged post-operative discomfort
When used efficaciously and ethically, lasers have proved to be an essential tool in endodontic treatments. With the development of thinner, more flexible and durable laser tips, laser applications in endodontics have increased and will keep on increasing.
With the advent of Lasers, the complex procedures have become easier and time-saving. Also, the ability to care for patients has been improvised to much greater extent. Thus, Lasers when employed for Endodontics provides an array of synergistic outcomes beneficial for both clinicians and patients.
About The Author:
Dr. Shanin Farista M.D.S (Conservative Dentist and Endodontist)
Has persuaded her Diploma in Laser Dentistry from USA. Currently, she is an Assistant Professor in the Department of Conservative Dentistry and Endodontics at Chhattisgarh Dental College and Research Institute. Speaker and Hands-On Trainer for Various Soft tissue and Hard tissue Lasers module at Divas in Laser. She has been a co-mentor and co-guide for various short courses, fellowship modules, workshops, skill training sessions and live demonstrations at various places for Lasers in Dentistry and Endodontics in India. Speaker at various platforms for Webinars and Whatsappinars. She is Editorial Board Member for World Journal of Advanced Scientific Research. She is in Board of Dentistry from India at GOMHA (Global Outreach Medical and Health Association). A freelancer consultant as Laser Endodontist and Restorative Dentist at Mumbai and Chhattisgarh. To her credit there are several original research paper, national and international publications all pertaining to Endodontics and Lasers in dentistry. Awarded as Emerging Dental Speaker 2018, Best Dental Organization 2018 (Divas in Laser), Excellence in Laser Dentistry 2018, Best Clinical Team of the year 2016 and Best PG Student in Conservative Dentistry and Endodontics in 2016. Serving honorarily at Aga Khan Health Services, India since 5 years, Angel Dentist Organization and Being Social since two years.