drlantran
- Aug 2, 2022
- 8 min read

August Literature Review

Compiled by Dr Igor Cernavin, Prosthodontist, Honorary Senior Fellow University of Melbourne School of Medicine, Dentistry and Health Sciences, and Australian representative of World Federation of Laser Dentistry (WFLD)

Chery, Jerry et al1 compared pediatric dental resident’s comfort levels and cavity preparation time using an Er, Cr:YSGG laser versus a conventional high-speed handpiece. They concluded that the total preparation time required for restorative treatment with a laser was significantly higher than the total time with a high-speed handpiece. Additionally, the comfort level was also lower using a laser compared to a high-speed preparation.

AlBalkhi, Mohand and Hamadah, Omar2 published a study to determine the effectiveness of different pulse durations (PD) and the water/air (W/A) cooling ratio of the Er:YAG 2940nm laser that are required for debonding porcelain laminate veneers (PLV), by investigation of the time needed for PLV debonding and the changes in dental pulp temperature (DT). They concluded that using the 50 or 100s PD of the Er:YAG laser was more efficient than 300s in reducing debonding time of PLVs with minimal change in pulp temperature. W/A cooling ratio had minimal influence on the DT of PLV.

Alkan, Ismet Ilke et al3 published the results of a clinical trial evaluating the efficiency of combined air polishing and Nd:YAG laser application in addition to scaling and root planning in treatment of periodontal pockets of stage III grade C periodontitis patients which may be of interest to the readers.

Lopes, Camila de Carvalho Almanca and coworkers4 published a systematic review of the effectiveness of photobiomodulation therapy on human bone healing in dentistry. The abstract is reproduced in full.

Background: Despite the association, possible causality, and contradictory results, numerous studies evaluate photobiomodulation (PBM) therapy on the process of human bone healing. It is of paramount importance to review the available literature to elucidate the effect of laser on the bone healing process in dentistry. Objective: This systematic review analyzes the effectiveness of PBM therapy to improve bone healing in dentistry. Methods: A systematic search of studies published up to September 2021 and listed in PubMed, Cochrane Library, and Embase databases and registered on PROSPERO (CRD42020212790). Twenty-five studies were selected. Results: The most used device was diode laser. PBM therapy parameters varied greatly. From the 25 selected studies, 17 had the primary outcome bone healing. Of these, 11 studies revealed improvement in bone healing with PBM therapy and six studies suggested no effect. The other eight studies evaluated secondary parameters. In seven studies, some of the clinical parameters were improved with the PBM therapy. Conclusions: Within the limitations of this systematic review, bone healing in dentistry was improved with the use of PBM. PBM therapy can promote anti-inflammatory and analgesic effects, improve healing, as well as enhance quality of life related to oral health. Within the areas analyzed in dentistry, laser parameters varied greatly, becoming difficult to consider a definite protocol as a proper one.

Kermanshah, Hamid et al5 evaluated the effect of photobiomodulation therapy (PBMT) with 915 nm wavelength diode laser on pain reduction during maxillary incisor local infiltration in a randomized clinical trial study. They found that it reduced pain during infiltration on maxillary incisors and that anxiety experience of the dental injection had no significant effect on the pain perception scale.

Mocuta Boioga and coworkers6 compared the influence of the Nd:YAG Laser (1064 nm) and the Diode Laser (980 nm) on the effect on enamel around orthodontic brackets and concluded that the that the best improvement of enamel chemical composition was obtained with Nd:YAG irradiation.

Torkzaban, Parviz et al7 compared the efficacy of the Er,Cr:YAGG laser and the conventional method of periodontal flapsurgery and concluded that the Er,Cr:YSGG laser assisted periodontal flap surgery resulted in similar treatment outcomes to the conventional method and may be considered as a safe and effective treatment modality.

Lima and coworkers8 evaluated the pre-irradiation time using PDT (diode laser associated with 0.01% methylene blue) to decrease the number of microorganisms in the visible plaque in permanent teeth. They found that it reduced the number of colony-forming units of mature bacterial biofilms in vivo.

Chen et al9 published an article about the effect of low-level blue LED light on dental pulp stem cells. The abstract is reproduced in full.

Human dental pulp stem cells (hDPSCs) have attracted tremendous attention in tissue regeneration engineering due to their excellent multidirectional differentiation potential. Photobiomodulation (PBM) using low-level light-emitting diodes (LEDs) or lasers has been proved to promote the osteogenesis of mesenchymal stem cells. However, the effect of LEDs on osteogenic differentiation of hDPSCs has little published data. In this work, the effect of blue LEDs with different energy densities of 2, 4, 6, 8, 10J/cm2 on osteogenic differentiation of hDPSCs was examined by using in vitro ALP staining, ALP activity, mineralization, and real-time PCR. The results showed that compared with the control group, osteogenic differentiation was significantly enhanced in blue LEDs treated groups. As the energy density increased, the level of osteogenesis initially increased and then decreased reaching the highest level at 6J/cm2. Transient receptor potential vanilloid 1 (TRPV1), a Ca2+ ion channel, was believed to be a potential player in osteogenesis by photobiomodulation. By immunofluorescence assay, calcium influx assay, PCR, and ALP staining, it was shown that blue LEDs irradiation can increase the activity of TRPV1 and intracellular calcium levels similarly to the agonist of TRPV1 capsaicin. Additionally, pretreatment with capsazepine, a selective TRPV1 inhibitor, was able to abrogate the osteogenic effect of blue LEDs. In conclusion, these findings proposed that blue LEDs can promote the osteogenesis of hDPSCs within the appropriate range (4-8J/cm2) during culture of osteogenic medium, and TRPV1/Ca2+ may be an essential signaling pathway involved in blue LEDs-induced osteogenesis, providing new insights for the use of hDPSCs in tissue regeneration engineering.

Li, Zhongqiang and coworkers10 published a study describing the use of indocyanine green delivery for dental imaging.

The abstract is reproduced in full.

SIGNIFICANCE: X-ray imaging serves as the mainstream imaging in dentistry, but it involves risk of ionizing radiation.

AIM: This study presents the feasibility of indocyanine green-assisted near-infrared fluorescence (ICG-NIRF) dental imaging with 785-nm NIR laser in the first (ICG-NIRF-I: 700 to 1000nm) and second (ICG-NIRF-II: 1000 to 1700nm) NIR wavelengths.

APPROACH: Sprague Dawley rats with different postnatal days were used as animal models. ICG, as a fluorescence agent, was delivered to dental structures by subcutaneous injection (SC) and oral administration (OA).

RESULTS: For SC method, erupted and unerupted molars could be observed from ICG-NIRF images at a short imaging time (<1min). ICG-NIRF-II could achieve a better image contrast in unerupted molars at 24h after ICG injection. The OA could serve as a non-invasive method for ICG delivery; it could also cause the glow-in-dark effect in unerupted molars. For erupted molars, OA can be considered as mouthwash and exhibits outstanding performance for delivery of ICG dye; erupted molar structures could be observed at a short imaging time (<1min) and low ICG dose (0.05mg/kg).

CONCLUSIONS: Overall, ICG-NIRF with mouthwash could perform in-vivo dental imaging in two NIR wavelengths at a short time and low ICG dose.

Vande et al11 published a systematic review and meta-analysis on the effectiveness of photobiomodulation therapy using low level laser therapy around dental implants. They concluded that it had a positive effect on implant stability during the early stages of healing and can be considered for patients with dental implants.

Al-Shamiri and coworkers12 published a systematic review on the efficacy of laser therapy for alveolar osteitis and concluded that it was effective.

Ghaffar et al13 assessed the effect of low-level laser therapy (LLLT) on overall leveling and alignment time of mandibular anterior crowding and associated pain after initial archwire placement. They concluded that it was effective.

Qu, Changxing and coworkers14 systemically analysed the effects of photobiomodulation therapy (PBMT) on implant stability and postoperative recovery and found that the effects of PBMT on implant stability and postoperative recovery may be limited.

Xu, Dan; Wang, et al15 compared the efficacy of three surgically assisted permanent anterior tooth eruption methods (laser surgery, electrosurgery and routine surgery) in children. They found that laser surgery and high-frequency electrosurgery have good efficacy, little pain and high operability, which can be considered as a better method to aid teeth eruption.

Yaneva and coworkers16 examined the clinical effectiveness of fibreless Er:YAG laser used for scaling and root planning and compared it with a conventional treatment with Gracey curettes.

They concluded that it can be used as a single treatment modality for subgingival scaling and root planning resulting in greater improvements in all recorded data in contrast to conventional treatment.

Rahman et al17 published a review of the use of photodynamic therapy for peri-implant diseases which readers may find of interest.

References:

1. Chery, Jerry; Freitas, Vanessa; (...); Gupta, Apeksha. Comparison of Cavity Preparation Times Using Conventional High-Speed Handpiece Versus Er, Cr:YSGG Laser: A Pilot Study with Pediatric Dental Residents. 2022-Mar-15 | Pediatric dentistry 44 (2) , pp.90-94

2. .AlBalkhi, Mohand and Hamadah, Omar. Influence of pulse duration and water/air cooling ratio on the efficiency of Er:YAG 2940nm laser in debonding of porcelain laminate veneers: An in vitro study. 2022-Apr-29 | Clinical and experimental dental research.

3. Alkan, Ismet Ilke; Akkaya, Hazal Ustunel and Saglam, Mehmet. The effectiveness of scaling and root planing with combined application of air polishing and Nd:YAG laser in periodontal pockets of stage III grade C periodontitis patients: a single-blinded randomized clinical trial. 2022-May-03 | Clinical oral investiga

4. Lopes, Camila de Carvalho Almanca; Limirio, Joao Pedro Justino Oliveira; (...); Limirio, Pedro Henrique Justino Oliveira. Effectiveness of Photobiomodulation Therapy on Human Bone Healing in Dentistry: A Systematic Review. 2022-May-06 | Photobiomodulation, photomedicine, and laser surgery.

5. Kermanshah, Hamid; Chiniforush, Nasim; Kolahdouz Mohammadi, Mahsa; Motevasselian, Fariba. Effect of Photobiomodulation Therapy with 915 nm Diode Laser on Pain Perception During Local Anesthesia of Maxillary Incisors: A Randomized Controlled Trial. Photochemistry and photobiology. Published 2022-May-12. DOI. 10.1111/php.13644