Laser Literature Review January 2021

Compiled by Dr Igor Cernavin, Prosthodontist, Honorary Senior Fellow University of Melbourne School of Medicine, Dentistry and Health Sciences, Director and Cofounder of the Asia Pacific Institute of Dental Education and Research (AIDER), Australian representative of World Federation of Laser Dentistry (WFLD)

Park, So-Hyun and coworkers1 compared the effectiveness of decontamination on oral biofilm-contaminated titanium surfaces using Er:YAG laser, Er, Cr:YSGG laser, and plastic curette and concluded that both laser systems produced a lower bacterial count than curette .

Baser Keklikci, et al2 investigated the effects of 405-nm, 532-nm, 650-nm, and 950-nm wavelengths of LLLTs on the orthodontic tooth movement in rats by using histological and immunohistochemical methods. They found that LLLT with 650-nm wavelength increases orthodontic tooth movement more than 405-nm, 532-nm, and 940-nm LLLTs. The 940-nm and 650-nm LLLTs also increase the bone area between the roots by more than 405-nm and 532-nm wavelengths.

Fraga and coworkers3 examined the efficacy of antimicrobial photodynamic therapy (aPDT) and low-level laser therapy (LLLT) in reducing postoperative pain and oedema after molar extractions. They found that the combined use of aPDT and LLLT was effective in reducing postoperative pain and suggest that these procedures can be applied in everyday surgical practice.

Fahlstedt et al4 published a study to estimate the implant temperature surface following irradiation with a double wavelength (2780nm Er,Cr:YSGG and 940nm diode) laser and concluded that it did not critically influence the implant surface.

Lin and coworkers5 examined the molecular effects of the Er:YAG laser in its ability to enhance periodontal healing and concluded that it may accelerate the regeneration process of periodontal tissue through enhancement of their proliferative and mobile activities as well as Gelactin-7 induction.

Pirmoradian et al6 studied the effect of photobiomodulation on relapse in rapid maxillary expansion in rats and found that it proved to be beneficial.

Vendramini and coworkers7 analyzed the antimicrobial effect of PDT on intracanal biofilm by reviewing the literature and concluded that it was effective when used as an adjunct to the regular endodontic technique, but because of the many different studies examined, its effect was not accurately quantified.

Civak et al8 compared patient postoperative pain, swelling, and trismus after usage of rotary instruments, piezosurgery, and Er:YAG lasers in mandibular third-molar extraction. They concluded that piezosurgery, and Er:YAG lasers are good alternatives to rotary instruments, but are slower.

Coelho and coworkers9 conducted a systematic review on the effect of different cavity disinfectants on a restoration’s adhesion and clinical success. The abstract is reproduced in full.

Cavity disinfection becomes an important step before a dental restorative procedure. The disinfection can be obtained cleaning the dental cavity with antimicrobial agents before the use of adhesive systems. The aim of this study was to conduct a systematic review on the effect of different cavity disinfectants on restorations' adhesion and clinical success. A search was carried out through the Cochrane Library, PubMed, and Web of Science. In vitro and in situ studies reporting results on dentin bond strength tests, and clinical studies published until August 2020, in English, Spanish and Portuguese were included. The methodological quality assessment of the clinical studies was carried out using the Revised Cochrane risk-of-bias tool. Chlorhexidine could preserve adhesion to dentin. EDTA and ethanol had positive results that should be further confirmed. Given the significant lack of scientific evidence, the use of lasers, fluoridated agents, sodium hypochlorite, or other products as cavity disinfectants should be avoided. Chlorhexidine is a safe option for cavity disinfection with adequate preservation of adhesion to dentin. Moreover, future researches should be focused on the efficacy of these disinfectants against cariogenic bacteria and their best application methods.

Lopez, et al10 published a systematic review of the literature regarding the antimicrobial effects of photodynamic therapy (PDT) on multi-bacterial species in periodontitis and peri-implantitis disease which demonstrated significant reduction in the bacterial load in periodontal pocket and dental implant surface with the use of PDT.

Hakimiha and coworkers11 assessed the efficacy of photobiomodulation (PBM) therapy on neurosensory recovery of patients with inferior alveolar nerve injury following third molar surgery or dental implant placement. Thea abstract is reproduced in full.

OBJECTIVE: The present systematic review aimed to assess the efficacy of photobiomodulation (PBM) therapy on neurosensory recovery of patients with inferior alveolar nerve injury following third molar surgery or dental implant placement.

METHOD AND MATERIALS: An electronic search was carried out in Scopus, Embase, Medline, PubMed, Web of Science, Cochrane Library, and Google Scholar databases. Among 1,122 identified papers, seven articles (three RCTs, one observational study, and three case series) met the inclusion criteria. <br />Results: Time lapse from nerve injury to the onset of PBM therapy varied widely from 2days to 4years. The number of patients in each study ranged between 4 and 74. In the majority of the studies, PBM was done using a diode laser at wavelengths ?in the range of 808 to 830nm with power of 5 to 500mW and radiation dose of 3 to 244 J/cm2. Two out of three RCTs found significant neurosensory recovery in the patients who received PBM therapy compared to the controls. The observational study and all case series reported significant improvement in the neurosensory status following PBM therapy. The degree of neurosensory recovery was found to be greater in younger patients and those who received the treatment within 6months following the injury. <br />Conclusions: Due to the limited number of well-designed RCTs and small number of patients in each study, it is not possible to make a clear conclusion about the efficacy of PBM therapy on neurosensory recovery in patients with inferior alveolar nerve injury following third molar or implant procedures. Considering the possibility of spontaneous inferior alveolar nerve recovery during this period, the conclusion based on the studies with no control group should be interpreted with caution.

Peixoto et al12 evaluated current studies to establish and compare the efficacy of traditional and laser acupuncture in reducing the signs and symptoms of temporomandibular disorders and concluded that both were effective when used with a splint.

Abdelkarim-Elafifi, Haitham and coworkers13 published a study comparing aerosol generation when using rotary instruments and the Er,Cr:YSGG laser which is very topical given the current COVID problems. They concluded that the laser generates 70% less in aerosols than rotary instruments.


1. Park, So-Hyun; Kim, Ok-Joon; Chung, Hyun-Ju; et al. Effect of a Er, Cr:YSGG laser and a Er:YAG laser treatment on oral biofilm-contaminated titanium. Journal of applied oral science : revista FOB Volume: ‏ 28 Pages: ‏ e20200528 Published: ‏ 2020.

2. Baser Keklikci, Hasibe; Yagci, Ahmet; Yay, Arzu Hanim; et al. Effects of 405-, 532-, 650-, and 940-nm wavelengths of low-level laser therapies on orthodontic tooth movement in rats. Progress in orthodontics Volume: ‏ 21 Issue: ‏ 1 Pages: ‏ 43 Published: ‏ 2020 Dec 01.

3. Fraga, Renato Silva; Antunes, Livia Azeredo Alves; Fialho, Walter Luis Soares; et al. Do Antimicrobial Photodynamic Therapy and Low-Level Laser Therapy Minimize Postoperative Pain and Edema After Molar Extraction? Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons Volume: ‏ 78 Issue: ‏ 12 Pages: ‏ 2155.e1-2155.e10 Published: ‏ 2020-Dec (Epub 2020 Aug 07)

4. Fahlstedt, Peter; Bunaes, Dagmar F; Lie, Stein Atle; et al. Dental implant surface temperatures following double wavelength (2780/940nm) laser irradiation in vitro. Clinical and experimental dental research Published: ‏ 2020-Dec-04 (Epub 2020 Dec 04).