Histological effects of photobiomodulation on delayed tooth replantation: a systematic review.

This systematic review evaluated preclinical studies to assess whether PBM has a more favorable histological response than other treatments used before delayed replantation of avulsed teeth. This review followed the PRISMA checklist and was registered in PROSPERO. MEDLINE (PubMed), Embase, Scopus and Web of Science were searched from their inception to July 14, 2022. Data were independently extracted by two reviewers. Data were collected about species, number of animals, number and type of teeth, groups evaluated, extra-alveolar time, parameters for PBM and other study groups, presence and characteristics of containment, observation time points, evaluation methods, characteristics evaluated, and significant results. The ARRIVE and SYRCLE tools were used to assess the methodological quality and risk of bias (RoB) of the studies. After screening, six studies were included in the review synthesis. Three of the four studies that evaluated root resorption as an outcome found that PBM decreases its occurrence after delayed tooth replantation. A meta-analysis was not conducted because some data were missing in the included studies. Half of the studies evaluating ankylosis found an increase in its occurrence after PBM. Two studies evaluated inflammatory responses and found a reduction of inflammation after PBM. In general, studies had high methodological heterogeneity, intermediate reporting quality and high RoB. Despite the methodological quality and RoB limitations of the studies, the histological responses after delayed tooth replantation were more favourable in the PBM groups. Preclinical studies supported by guidelines should define laser parameters for future clinical studies.

Efficacy of photobiomodulation in the treatment of avulsed teeth: A systematic review of animal studies.

The objective of this systematic review was to evaluate the effectiveness of photobiomodulation therapy (PBM) in managing avulsed teeth. This systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (i.e., "PRISMA") statement 2020 and was registered in the International Prospective Register of Systematic Reviews (i.e., PROSPERO) with number CRD42022362198. The participants, intervention, comparison, outcomes, and study design (i.e., PICOS) for the present study considered the following question: "Does the use of laser PBM in the treatment of teeth with avulsion influence tissue repair performance?" A literature search was performed in PubMed/MEDLINE, Embase, Web of Science, Cochrane Library, and ProQuest databases until January 2023. The SYRCLE's RoB tool (Systematic Review Center for Laboratory Animal Experimentation) for animal studies were used for quality assessment. A total of 7 in vivo studies published between 2011 and 2018 were included in this systematic review for qualitative analysis. All studies used Wistar rats, totaling 368 specimens that simulated tooth avulsion trauma. The effect of photodynamic therapy in the treatment of avulsed teeth was positive in 5 studies (significant increase in tissue repair) and negative in 2 studies, in which both studies with negative results kept teeth in saline solution before reimplantation and showed the longest time and power of laser application. PBM appears to be effective for tissue repair in the treatment of avulsed teeth, depending on the means of conservation of the avulsed tooth and the laser application protocol.

Effect of low-level laser therapy (λ780 nm) on the mechanically damaged dentin-pulp complex in a model of extrusive luxation in rat incisors.

In order to regenerate the dental pulp, many strategies have been developed as phototherapy. In the pulp repair, we do not know if gallium-aluminum-arsenide (GaAlAs) laser preserves the primary odontoblasts or stimulates the formation of more dentin matrix when dental pulp is damaged. The aim of the present study was to examine the effect of laser phototherapy (λ780 nm) on vascularization, inflammation, density of the primary odontoblast layer, and formation of reactionary and reparative dentin in the dental pulp by provoking extrusion of the rat incisor. The upper incisors were extruded 3 mm and then repositioned into their original sockets followed by a laser irradiation of the palatal mucosa (λ = 780 nm; p = 70 mW; CW; 4.2 J/cm2; 60 s) every 48 h. Non-traumatized and/or non-irradiated incisors were used as the controls. At 8 and 30 days after surgery, incisors were processed for histological and histomorphometric analysis. Morphological analysis revealed no differences in vascularization between groups, but showed discrete inflammation in some non-irradiated and injured specimens, which correlated with a more irregular reparative dentin. The density of primary odontoblasts in the groups treated with lasers was higher when compared to non-irradiated groups, but no statistically significant difference between groups (p > 0.05). The thickness of the tertiary dentin was increased in both traumatized groups with no statistically significant difference between non-irradiated and irradiated groups (p > 0.05).The present findings revealed that the GaAlAs laser induced small changes on dentin-pulp complex, with more regular dentin matrix in the irradiated dental pulps.

Low-level laser therapy effects in traumatized permanent teeth with extrusive luxation in an orthodontic patient.

The aim of this case report was to present and evaluate the effect of low-level laser therapy on traumatized permanent teeth with extrusive luxation in an orthodontic patient. The treatment and follow-up evaluation of two orally luxated maxillary permanent central incisors in a 19-year-old man is described. Detailed anamnesis was taken, and extraoral, intraoral, radiographic examinations and electrical and thermal pulpal tests were performed to determine the type of the luxation and the further treatment protocol. Teeth were splinted with composite resin, and antibiotic therapy was prescribed. Low-level laser therapy was applied for 25 sessions. No root canal treatment was applied to the teeth. Continuation of the orthodontic treatment was restarted after 6 months. No sign of clinical or radiographic pathology was detected after 2 years from the end of the treatment. Teeth were identified healthy and sound without any root canal intervention. Treatments with low-level laser applications may be evaluated as noninvasive alternative treatment options in comparison with endodontic treatment for teeth with extrusive luxation more than 2 mm, especially for those who have orthodontic treatment needs.

Lasers and pediatric dental care.

There are several types of lasers that will allow pediatric dentists to remove soft tissue (such as diode or Neodynium:Yttrium-Aluminum-Garnet (Nd:YAG) lasers) or remove both hard and soft tissue (such as the Erbium:YAG laser), in addition to photobiostimulation or therapeutic lasers that produce their healing benefits without producing heat. Lasers allow pediatric dentists to provide optimal care without many of the fear factors that result from conventional dental techniques. Lasers are extremely safe and effective when the user has a proper understanding of laser physics. Using lasers for caries removal, bone removal, and soft tissue treatment can reduce postoperative discomfort and infection and make it possible for dentists to provide safe, simple treatments.