Influence of Intravascular Laser Irradiation of Blood (ILIB) on inflammatory cytokines and nitric oxide in vivo: a systematic review.

The use of Intravascular Laser Irradiation of Blood (ILIB) as a treatment or adjunct tool has been used around the world since the 1980s. So that more professionals can deliver benefits to their patients in different areas of health, it is necessary to understand in depth the mechanisms of laser action at the molecular level, for correct indication and success in the treatment. To analyze works that evaluated the influence of ILIB on inflammatory cytokines and nitric oxide (NO) in animals and humans. The literature search was carried out between February and April 2023 in Pubmed, Medline, Web of Science, SciELO, Lilacs database. The risk of bias was assessed using the bias table where the authors performed the analyzes of all articles with the risk of bias domains. The methodology was defined following the PRISMA guidelines (Preferred Systematic Reviews and MetaAnalysis Report). The search retrieved 135 possibly relevant articles. After removing duplicates, according to the eligibility criteria, evaluation of titles and review of abstracts, in the end, 6 articles were included. An increase in anti-inflammatory cytokines, a decrease in pro-inflammatory cytokines and an increase in NO can be observed. The wavelengths used ranged from 660 to 808 nm when using a low intensity laser and when using a VIP light source 480-3400 nm, they also differed in terms of the light emission pattern. ILIB may be a complementary treatment option for patients who have comorbidities that lead to systemic inflammation.

Laser acupuncture to reduce temporomandibular disorder (TMD) symptoms: systematic review and meta-analysis.

The application of low-level laser therapy (LLLT) to acupuncture points may produce effects similar to that of needle stimulation in patients with temporomandibular disorders (TMD). This systematic review was conducted according to the Cochrane Collaboration guidelines and aimed to address clinical questions using the following strategy: Patient/Problem, Intervention, Comparison, and Outcome (PICO). A comprehensive literature search was performed upto April 26, 2023, across nine electronic databases (BVS, PubMed, Scopus, Embase, Web of Science, ScienceDirect, Cochrane Library, Latin American and Caribbean Health Sciences Literature (LILACS), and Google Scholar) supplemented with gray literature. The risk of bias in randomized and nonrandomized clinical trials was assessed using two tools: risk-of-bias (RoB) 2 and Risk Of Bias In Non-randomised Studies-of Interventions (ROBINS-I). Meta-analysis involved the extraction of mean and standard deviation values for spontaneous pain and mouth opening levels. Seven studies were included in this review, all of which used LLLT. The applied wavelengths ranged from 690 to 810 nm without significant variations in light emission patterns. LLLT demonstrated a significant reduction in instantaneous pain levels (standard mean difference [SMD] = 3.85; 95% confidence interval [CI] = 2.09, 5.62; p < 0.003) and an improvement in instantaneous mouth opening ability (mean difference [SMD] = -7.15; 95% CI = -11.73, -2.58; p < 0.002), with low certainty of evidence. LLLT may alleviate symptoms in patients with TMD; however, caution should be exercised when interpreting the results because of protocol variations among studies and the limited number of studies included in the meta-analysis.

Laser acupuncture in the treatment of neuropathies in dentistry: a systematic review.

Laser acupuncture can be used to treat neurosensory alterations and motor disorders caused by dental treatments. This study aimed to review the existing literature on the effects of laser acupuncture on neuropathies in the context of dentistry and to search for treatment modalities in which this technique is used. This systematic review was conducted in accordance with the Cochrane Collaboration guidelines and the PICOS strategy. Randomized clinical trials that evaluated laser acupuncture as a primary intervention for facial neuropathy were included. We searched the database for relevant studies and manually searched the gray literature until April 2022, and finally included four studies. The study was considered eligible if it included patients with paresthesia, facial paralysis, or neuralgia, neuropathies within dentistry, and referred to the application of laser acupuncture as a treatment method. The risk of bias was assessed using the RoB 2 tool. It was observed that the recommended wavelengths ranged from 790 nm to 810 nm, with a frequency of at least two applications per week, and to a greater or lesser degree, all evaluated studies obtained an improvement in sensory or motor recovery of the facial nerves. The use of laser acupuncture presented itself as a viable alternative in dentistry for the treatment of paresthesia and facial paralysis due to its therapeutic potential in neuropathic treatment (CRD42022344339).

Effect of low-level laser stimulation of acupuncture points in pediatric dentistry: a systematic review.

The biomodulatory potential of low-level laser therapy (LLLT) has prompted investigations of different outcomes in health. One line of research is the stimulation of acupuncture points for the relief of different signs and symptoms related to the stomatognathic system. In dentistry, some studies in pediatric dentistry have demonstrated the benefit of LLLT therapies in the management of dental anxiety in children. This systematic review aimed to analyze previous clinical studies on the application of LLLT at acupoints among pediatric dental patients. This systematic review was conducted according to the Cochrane Collaboration guidelines and the population, intervention, comparison, and outcome strategy. A broad literature search up to June 17, 2022, was performed using four electronic databases (PubMed, Scopus, Embase, and Google Scholar). The risk of bias in randomized clinical trials was assessed using the RoB 2 tool. A total of four studies using LLLT for photobiomodulation were included (n = 4). The most common wavelengths used were in the infrared range (variation between 716 nm and 980 nm). There were little variations in the application time (14 s to 1 min) and exposure dose (1 to 5 joules). LLLT acted positively on different acupuncture points. LLLT provided various benefits and optimized dental practice by reducing the gag reflex during radiography and impression taking, preanesthetic pain, and symptoms of sleep bruxism in the pediatric dental population. Only one of the evaluated studies had a high risk of bias. The LLLT at acupuncture points is associated with positive results on sleep bruxism, preanesthetic pain, and gag reflex in pediatric dentistry. Future research studies should prioritize standardization of the study design and the methods of analysis.

Do erbium lasers promote changes in the tooth enamel during debonding of ceramic laminate veneers? A systematic review.

The longevity of ceramic laminate veneers can be influenced by several factors, which can result in the need for a removal process. Laser removal has emerged as a good alternative to facilitate the procedure, and its repercussions on tooth enamel have been investigated. We aimed to evaluate the efficacy of erbium lasers for debonding ceramic laminate veneers without damaging the tooth enamel. This systematic review based on the PICOS model adhered to the PRISMA statement. The PubMed/MEDLINE, Web of Science, Embase, and Scopus databases were systematically searched until December 1, 2022, and 2902 studies were retrieved. After screening, four in vitro studies that analyzed the dental morphology using scanning electron microscopy, optical analysis, stereomicroscopy, or x-ray dispersion spectroscopy were included. The risk of bias was assessed using the Cochrane Collaboration tool. Our findings suggest that erbium lasers are useful for ceramic laminate veneer removal without damaging the tooth enamel. However, the removal is influenced by the type and thickness of ceramic and type of cement used. It could be concluded that the application of Erbium laser did not promote superficial changes in the dental enamel. This effect was observed in all analysis performed.

Photobiomodulation impacts the levels of inflammatory mediators during orthodontic tooth movement? A systematic review with meta-analysis.

During orthodontic tooth movement (OTM), there is the release of cytokines in the gingival crevicular fluid (GCF) that are supposed to participate in the bone remodeling. This systematic review aimed at assessing the effects of photobiomodulation (PBM) on the levels of these cytokines during OTM. This systematic review according to Cochrane Collaboration guidelines aimed to answer the clinical question following the PICOS strategy. The broad search in the literature was performed before 05 April, 2021 in six electronic databases (Pubmed, Web of Science, Scopus, Embase, Cochrane, Biblioteca Virtual de Saúde) and supplemented by the grey literature. The risk of bias of randomized and non-randomized clinical trials was evaluated by two tools: RoB 2 and ROBINS-I. Mean and standard deviation of cytokine levels was extracted to meta-analysis, and the GRADE system was applied to assess the quality of the evidence. Nine studies were included in this review. Low-level laser therapy (LLLT) was the photobiomodulation type used in most of the studies (n = 8). The wavelengths used varied from 618 to 980 nm and also differed concerning the light emission pattern. LLLT increased the levels of IL-1ß, IL-8, OPN, and PGE2, but not TNF-α1, TGF-ß1. The levels of IL6, RANKL, and OPG presented conflicting results. LLLT was statistically associated with an increase of IL-1ß levels (standard mean difference [SMD] = 1.99; 95% confidence interval = 0.66 to 3.33; p < 0.001) with low certainty of evidence. LLLT may increase the levels of IL-1ß and other cytokines; however, the results should be interpreted with caution due to protocol variations between studies, and the few studies added in the meta-analysis.

Effect of Auricular Acupuncture on the Reduction of Symptoms Related to Sleep Disorders, Anxiety and Temporomandibular Disorder (TMD).

BACKGROUND: Auricular acupuncture (AA) is a complementary/integrative therapy, and can be used as adjuvant treatment in sleep disorders, anxiety and the painful symptomatology of temporomandibular disorders (TMDs). OBJECTIVE: The aim of this investigation was to evaluate the effectiveness of AA in reducing the symptoms of sleep disorders, anxiety and TMDs by applying the Fletcher and Luckett, Beck-BAI and RDC/TMD questionnaires: Axis II, respectively. DESIGN: This was a nonrandomized clinical trial in which AA was administered to patients between the ages of 20 and 45 years from the School of Dentistry at Ribeirão Preto, São Paolo, Brazil, who had at least one of the following: sleep disorder, anxiety or TMD. INTERVENTION: Mustard seeds were applied to predetermined auricular acupoints including: Shen Men, neurovegetative system (sympathetic), kidney, anxiety, stomach, maxilla and mandible, liver and stress, once a week for 8 weeks. OUTCOME MEASURES: To analyze the reduction in sleep disorder symptoms, we used the Fletcher and Luckett questionnaire; for anxiety symptoms, the Beck-BAI questionnaire, and for the degree of chronic TMD pain, the RDC/TMD (Axis II) questionnaire. RESULTS: Data on sleep, anxiety and TMD disorders were analyzed via Fisher's exact, Wilcoxon and Chi-Square non-parametric tests (α = 0.05), respectively. Reduction in sleep disorder symptoms after the proposed intervention was verified, showed a statistically significant difference (P = .014). There was a reduction in mean anxiety score and a decrease in painful TMD symptoms, but no significant difference (P = .50; P = .947, respectively) before and after AA. CONCLUSION: In our study, AA was effective in reducing sleep disorder symptoms and our data suggests some relief of symptoms of anxiety and TMD pain.

Photosensitizers attenuate LPS-induced inflammation: implications in dentistry and general health.

Antimicrobial photodynamic therapy (aPDT) is a complementary therapeutic modality for periodontal and endodontic diseases, in which Gram-negative bacteria are directly involved. Currently, there are few evidences regarding the effects of aPDT on bacterial components such as lipopolysaccharide (LPS) and it would represent a major step forward in the clinical use of this therapy. In this context, this study aimed to evaluate the efficacy of different photosensitizers (PSs) used in aPDT in LPS inhibition. Four PSs were used in this study: methylene blue (MB), toluidine blue (TBO), new methylene blue (NMB), and curcumin (CUR). Different approaches to evaluate LPS interaction with PSs were used, such as spectrophotometry, Limulus amebocyte lysate (LAL) test, functional assays using mouse macrophages, and an in vivo model of LPS injection. Spectrophotometry showed that LPS decreased the absorbance of all PSs used, indicating interactions between the two species. LAL assay revealed significant differences in LPS concentrations upon pre-incubation with the different PSs. Interestingly, the inflammatory potential of LPS decreased after previous treatment with the four PSs, resulting in decreased secretion of inflammatory cytokines by macrophages. In vivo, pre-incubating curcumin with LPS prevented animals from undergoing septic shock within the established time. Using relevant models to study the inflammatory activity of LPS, we found that all PSs used in this work decreased LPS-induced inflammation, with a more striking effect observed for NMB and curcumin. These data advance the understanding of the mechanisms of LPS inhibition by PSs.

Efficacy of CO lasers in preventing dental caries in partially erupted first permanent molars: a randomized 18-month clinical trial.

The aim of this controlled randomized double-blinded clinical trial was to evaluate the use of a CO2 laser with or without topical application of acidulated fluorides in the prevention of dental caries in partially erupted first permanent molars. We selected 61 healthy children at high risk of caries, all between 6 and 8 (7.1 ± 0.8) years of age and with 4 partially erupted first permanent molars. A CO2 laser device emitting at 10.6 µm was used (0.5 W, 0.05 mJ per pulse, 10 kHz). Each first molar in an individual was randomly assigned to one treatment: (L) CO2 laser (0.066 J/cm2); (FL) 1.23% acidulated fluoride gel and CO2 laser (0.066 J/cm2); (V) 5% fluoride varnish, or (S) sealant (control). Patients were followed-up at 3, 6, 12, and 18 months after treatment, through direct visual examination and by an operator blinded to the treatments (kappa ≥ 0.70). The International Caries Detection and Assessment System (ICDAS-II) index was used to assess the soundness of tooth structure or the presence of white spot lesions, cavitated enamel, and/or dentin lesions. The Yildiz Visual Index was used to evaluate sealant retention. Results were evaluated using Kaplan-Meier survival analysis, and the hazard ratio of the treatments was estimated using shared frailty models with a gamma distribution, which considered the patient as a cluster. There were no significant differences among treatments compared to sealants. After 18 months, the use of a CO2 laser with or without acidulated fluorides was shown to be effective in preventing caries on the occlusal surface of partially erupted permanent first molars in children at high risk for caries.

Four-year clinical prospective follow-up of resin composite restoration after selective caries removal using Er:YAG laser.

OBJECTIVES: The aim of this study was to longitudinally evaluate, after a 4-year period, the clinical longevity of composite resin restoration compared to the baseline, after selective caries removal in permanent molars using Er:YAG laser or bur preparation with biomodification of dentin with the use of chlorhexidine. METHODS: Selective caries removal was performed on 80 teeth of 20 individuals who each had at least four active carious lesions. These lesions, located on occlusal surfaces of permanent molar counterparts, were removed using (i) Er:YAG laser biomodified with chlorhexidine, (ii) Er:YAG laser and application of deionized water, (iii) bur preparation biomodified with chlorhexidine, and (iv) bur preparation and application of deionized water. At the end of 4 years, 64 of the 80 restorations were evaluated in 16 individuals (n = 16). The restorations were evaluated, both clinically and photographically, using scanning electron microscopy (SEM) and pulp vitality analysis. The experimental data were statistically evaluated by kappa, Fisher's, and chi-square tests, with a significance level of 5%. The Kaplan-Meier test and the Cox regression analysis were used to evaluate the survival of the restorations. RESULTS: After 4 years of follow-up, there was a statistically significant difference in marginal discoloration criteria for all of the groups evaluated. For marginal adaptation criteria, there was a statistically significant difference for the Er:YAG laser group biomodified with chlorhexine (p = 0.050). For clinical and radiographic evaluation of pulp vitality, there were no statistically significant differences among the groups (p = 0.806). CONCLUSION: Er:YAG laser can be used for selective caries removal, regardless of dentin biomodification with chlorhexidine or application of deionized water, once it produced promising results in composite resin restorations after 4 years of follow-up, according to the criteria evaluated. The selective caries removal using Er:YAG laser or bur and the biomodification of dentin with the use of chlorhexidine did not influence the survival of composite resin restorations after the 4-year follow-up period. CLINICAL RELEVANCE: Composite resin restorations applied after selective caries removal using Er:YAG laser or burs, regardless of dentin biomodification with the use of chlorhexidine or application of deionized water, showed adequate clinical behavior after 4 years of follow-up.

Influence of pre-irradiation time employed in antimicrobial photodynamic therapy with diode laser.

The aim of the present study was to evaluate, in vitro, the effect of different pre-irradiation times of the photosensitizer in photodynamic therapy in biofilms formed by Streptococcus mutans and Candida albicans, through the evaluation of the microbial load. The factors under study were as follows: times of pre-irradiation of the photosensitizer in three levels (1, 2, or 5 min). For the control of the cariogenic dental biofilm with antimicrobial photodynamic therapy (aPDT), methylene blue (0.01%) was used in association with the diode laser (InGaAlP) with a wavelength of 660 nm. Chlorhexidine digluconate (0.12% CHX) and saline were used as positive and negative controls, respectively. The study design was carried out in complete and randomized blocks. The sample consisted of 15 S. mutans biofilms cultures, randomly divided into five groups and 15 C. albicans cultures, also divided into five groups. The experiment was performed in triplicate (n = 3) and the response variables were obtained through quantitative analysis of bacterial viability, expressed in colony-forming units (CFU) per square millimeter of the specimen area. The data were analyzed with the aid of the ANOVA one-way test and Tukey's post-test. All analyses were performed using the Graph Pad Prism 4.0 program, with a significance level of 5%. For the S. mutans group, only the saline solution presented a statistically significant difference when compared to the other treatments (p < 0.05), that is, the treatment with aPDT, irrespective of the irradiation time applied, was similar to the treatment with CHX and both were more effective in reducing cariogenic biofilm compared to saline. For the group of C. albicans, there was no statistical difference between the groups (p > 0.05). Therefore, it can be concluded that the treatment with aPDT reduced the number of CFUs of S. mutans in a similar way to CHX, independently of the pre-irradiation time applied. No effect of this therapy or of the different pre-irradiation times on the C. albicans biofilm could be observed. In this way, the pre-irradiation time of 1 min can be used to reduce the microbial load of S. mutans.

Mechanical, chemical and antimicrobial properties of a bisphenol A-free pit-and-fissure sealant.

PURPOSE: To evaluate, in vitro, mechanical, chemical and antimicrobial properties of Embrace Wetbond bisphenol A (BPA)-free pit-and-fissure sealant. METHODS: For the shear bond strength and microleakage tests, 135 healthy third molars were randomly divided into six groups, according to sealant [Fluroshield (FS) and Embrace Wetbond (EWB)] and contamination conditions (no contamination, contamination with saliva and contamination with water). In addition, EWB sealant was subjected to the following analyses: fluoride release using direct potentiometry, antimicrobial activity using the agar well diffusion method and quantification of BPA using gas chromatography and mass spectrometry. Data were analyzed statistically by ANOVA, Kruskal-Wallis test, Tukey's post-test, Dunn's post-test and Bonferroni post-test (α= 0.05). RESULTS: For shear bond strength, there was a statistically significant difference among the groups (P< 0.05), and FS presented the best results. Analysis of the microleakage results showed statistically significant differences among the groups (P< 0.05), except for EWB non-contaminated, contaminated with saliva, and contaminated with water (P> 0.05). FS without contamination presented the lowest microleakage of all groups (P< 0.05), followed by FS contaminated with saliva, and three groups in which EWB was used under different conditions. FS contaminated with water presented the highest microleakage (P< 0.05). EWB showed higher fluoride release in water and artificial saliva on the first day (P< 0.05). EWB had greater antimicrobial activity than FS. BPA and Bis-GMA were not detected in EWB. When used according to the manufacturer's instructions (i.e., under conditions of moisture contamination), EWB showed high fluoride release, high antimicrobial activity, no release of BPA or Bis-GMA and shear bond strength close to the minimum acceptable value. However, this sealant presented statistically significantly more microleakage than the other tested materials. CLINICAL SIGNIFICANCE: Knowing the adverse effects of BPA in the body, the present study has clinical relevance since it demonstrates some mechanical, chemical and antimicrobial properties of a BPA-free pit-and-fissure sealant.

Clinical evaluation of composite restorations in Er:YAG laser-prepared cavities re-wetting with chlorhexidine.

OBJECTIVES: The objective of this study was to evaluate longitudinally the composite restorations, performed in cavities prepared by Er:YAG or conventional bur, and dentin re-wetting with water or chlorhexidine. MATERIALS AND METHODS: Twenty individuals with four active caries with cavitation reaching the dentin located on the occlusal surface of molars counterparts are selected. The teeth of each individual were randomly assigned into four groups: (I) Er:YAG laser (260 mJ/4 Hz) re-wetting with chlorhexidine, (II) Er:YAG laser (260 mJ/4 Hz) re-wetting with deionized water, (III) conventional method re-wetting with chlorhexidine, and (IV) conventional method re-wetting with deionized water. The teeth were isolated, prepared cavities, phosphoric acid etching, and re-wetting according to previously assigned method. Restoration was performed employing the Single Bond 2 and Z350XT resin. Clinical follow-up was held after the polishing of the restoration (baseline) and 6 and 12 months of the making of the restoration using the modified USPHS criteria. The restorations were qualitatively analyzed by means of photographs. In the evaluation period, replicas of the restorations were analyzed by SEM. Data were analyzed by statistics using chi-square test (p < 0.05). RESULTS: After 12 months of clinical evaluation, groups prepared with laser and re-wetting with chlorhexidine and water showed the lowest marginal staining value. There was no statistical difference between the groups for other factors. SEM analysis revealed that a non-expressive amount of restorations showed gaps and irregularities of tooth-restoration interface after 6 and 12 months compared to the baseline. CONCLUSION: The restorations performed in laser-prepared cavities, regardless of the re-wetting, presented the best clinical performance over the evaluated period. CLINICAL RELEVANCE: Laser-prepared teeth, regardless of re-wetting, showed greater resistance to marginal discoloration.

Microleakage of Sealants after Phosphoric Acid, Er: YAG Laser and Air Abrasion Enamel Conditioning: Systematic Review and Meta-Analysis.

PURPOSE: The aim of this systematic review and meta-analysis is to answer the focused question: Does the application of phosphoric acid, Er:YAG laser and air abrasion enamel conditioning methods previous to the oclusal sealant application in human permanent molars influence the microleakage? STUDY DESIGN: A literature research was carried out in the Pubmed Medline, Web of Science, Scopus and Cochrane databases using with the MeSH terms and keyword search strategy. A supplemental hand search of the references of retrieved articles was also performed. Inclusion criteria comprised ex vivo studies (extracted teeth) with permanent human teeth that used chemical (phosphoric acid) or mechanical (Er:YAG laser and air abrasion) conditioning methods previous the sealant application. The studies should evaluate microleakage as an outcome. Meta-analysis pooled plot were obtained comparing the microleakage after pre-treatment with phosphoric acid, Er:YAG and air abrasion enamel conditioning for sealant application using RevMan software. RESULTS: The search resulted in 164 articles, 55 records were excluded because they were duplicated. The analysis of titles and abstracts resulted in the exclusion of 105 studies. Four studies were included in the systematic review and the meta-analysis. According to the risk of bias evaluation, the four studies were considered low risk of bias. The meta-analysis showed that phosphoric acid had lower microleakage than Er:YAG laser (p < 0.001) and air abrasion (p < 0.001), with heterogeinity of I2 = 0% and I2 = 71%, respectively. It was not found statistical difference when compared phosphoric acid and phosphoric acid combined with Er:YAG laser and air abrasion (p > 0.05). CONCLUSION: The evidence supports that the pretreatment with phosphoric acid leads lower microleakage in oclusal sealants than Er:YAG laser and air abrasion.

Caries removal in deciduous teeth using an Er:YAG laser: a randomized split-mouth clinical trial.

OBJECTIVES: The aim of the present clinical randomized split-mouth study was to evaluate the effectiveness and efficiency of an Er:YAG laser for caries removal in primary molars, microbiological dentin analysis, and clinical restorations after 1 year in 29 children. MATERIALS AND METHODS: The children's teeth were randomized into two groups: (I) an Er:YAG laser group and (II) a bur preparation group. The efficiency of the treatments (the time necessary for the removal of carious tissue) was evaluated based on the time spent on caries removal in the deciduous molars. The effectiveness (caries removal capacity) of the caries removal was determined by means of a blind test in which the examiner performed a tactile and visual examination of the dentin. Microbiological analysis was performed by counting the Streptococcus mutans and Lactobacillus sp in the remaining dentin. Clinical analysis of restorations was performed using the USPHS method in combination with photographs of restored teeth, 7 days after the restorative procedure and again after 1 year. All cavities were restored with the Adper Single Bond 2/Filtek Z350 system. The obtained data were analyzed with a significance level of 5 %. RESULTS: The Er:YAG laser was less effective and had the same efficacy as bur preparation during caries removal at the pulpal wall of deciduous molars. In the surrounding walls, bur preparation was the more effective method. Regardless of the method employed, the affected dentin in the pulpal wall had similar amounts of S. mutans and Lactobacillus sp. The restorations were clinically accepted by the USPHS method over a 1-year period. CONCLUSION: It can be concluded that caries removal with an Er:YAG laser has no influence on the clinical behavior of restorations. CLINICAL RELEVANCE: Irradiation with an Er:YAG laser is appropriate for caries removal in primary teeth.

Loss of structural water and carbonate of Nd:YAG laser-irradiated human enamel.

The objective of this study was to use Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM) to assess whether Nd:YAG laser irradiation associated with a dye or not alters the chemical constitution of the enamel. Fourteen enamel sections were randomly divided into two groups: (1) Nd:YAG and (2) dye + Nd:YAG. First, the untreated enamel surfaces were analyzed by FTIR to acquire the control absorption spectrum. Next, Group 2 received a layer of inactivated coal diluted in deionized water before laser treatment. Enamel samples belonging to groups 1 and 2 were then irradiated with a 1,064-nm Nd:YAG laser (80 mJ, 10 Hz) in the contact mode; the carbonate absorption band and the water absorption band were measured in each sample after irradiation. The water band was measured again 24 h, 48 h, and 7 days after irradiation. Group 1 had statistically similar water and carbonate contents before and after irradiation. Group 2 displayed significantly lower (p < 0.05) water content after irradiation, which remained constant along time at 24 and 48 h. After 7 days, the water content increased slightly, being statistically higher than in the other experimental periods, except for the control. The carbonate/phosphate ratio was measured only at the beginning, and after irradiation, it decreased only in Group 2 indicating carbonate loss (p < 0.05). Irradiation with 1,064-nm Nd:YAG laser associated with a dye reduces the carbonate and structural water content in the enamel.

CO2 laser as auxiliary in the debonding of ceramic brackets.

This study evaluated the temperature in the bonding composite and in the pulp chamber, the shear bond strength after the irradiation of CO2 lasers, and the Adhesive Remnant Index (ARI) after debonding of ceramic bracket. A hundred and five premolars were used: 30 to evaluate the temperature and 75 to test the resistance to shear and the ARI. To assess the temperature, different irradiation times (3 and 5 s), pulse duration (0.001 and 0.003 s), and output power (5, 8, and 10 W) were tested (total of 12 groups). During all the irradiation, specimens were immersed in thermal bath water at 37 °C. In the test and ARI evaluation, premolars were divided into five groups (n = 15) and were submitted to the following regimens of CO2 laser irradiation: I (5 W, pulse duration = 0.01 s, application time = 3 s), II (5 W, 0.03 s, 3 s), III (8 W, 0.01 s, 3 s), and IV (1 0 W, 0.01 s, 3 s). Group C (control) was not subjected to irradiation. ARI was measured after debonding of the bracket. Following irradiation of the lasers, the pulpal temperature was not higher than 5.5 °C in four of the study groups. Results were submitted to the ANOVA and Duncan's test. CO2 laser irradiation regimen IV was one in which the strength of debonding is 7.33 MPa. Therefore, CO2 laser may aid removal of ceramic brackets; it decreased the bond strength without increasing the excessive temperature excessively.

Auriculotherapy in a patient with Arnold Chiari malformation type II: Case report.

AIMS: Auriculotherapy is a therapeutic method of traditional Chinese Medicine in which a stimulus is exerted on the ear and activates energy channels throughout the body, helping to control anxiety, stress, pain, inflammation, illnesses chronic, and possibly can be used in patient with Arnold Chiari Malformation type II who have painful symptoms that are difficult to resolve. Thus, the aim of this article is to present a case in a patient with Chiari Malformation II where auriculotherapy and effect of laser therapy were performed, to relieve symptoms of agitation, anxiety and healing of self-mutilation injuries. CASE REPORT: Data from medical records were used to collect medical and dental history, complaints and treatments performed. Eight sessions of auriculotherapy and one of laser therapy were carried out in order to heal the lesions. The patient presented lower levels of anxiety, agitation and ceased the habit of self-mutilation and, consequently, the pain. CONCLUSIONS: The use of auriculotherapy led to a considerable improvement in the patient's painful condition and reduced anxiety, also benefiting the interaction with her family members and laser therapy promoted wound healing.

Temperature rise during Er:YAG cavity preparation of primary enamel.

This study aimed to assess in vitro thermal alterations taking place during the Er:YAG laser cavity preparation of primary tooth enamel at different energies and pulse repetition rates. Forty healthy human primary molars were bisected in a mesio-distal direction, thus providing 80 fragments. Two small orifices were made on the dentin surface to which type K thermocouples were attached. The fragments were individually fixed with wax in a cylindrical Plexiglass® abutment and randomly assigned to eight groups, according to the laser parameters (n = 10): G1 - 250 mJ/ 3 Hz, G2 - 250 mJ/ 4 Hz, G3 - 250 mJ/ 6 Hz, G4 - 250 mJ/10 Hz, G5 - 250 mJ/ 15 Hz, G6 - 300 mJ/ 3 Hz, G7 - 300 mJ/ 4 Hz and G8 - 300 mJ/ 6 Hz. An area of 4 mm(2) was delimited. Cavities were done (2 mm long × 2 mm wide × 1 mm thick) using non-contact (12 mm) and focused mode. Temperature values were registered from the start of laser irradiation until the end of cavity preparation. Data were analyzed by one-way ANOVA and Tukey test (p ≤ 0.05). Groups G1, G2, G6, and G7 were statistically similar and furnished the lowest mean values of temperature rise. The set 250 mJ/10 and 15 Hz yielded the highest temperature values. The sets 250 and 300 mJ and 6 Hz provided temperatures with mean values below the acceptable critical value, suggesting that these parameters ablate the primary tooth enamel. Moreover, the temperature elevation was directly related to the increase in the employed pulse repetition rates. In addition, there was no direct correlation between temperature rise and energy density. Therefore, it is important to use a lower pulse frequency, such as 300 mJ and 6 Hz, during cavity preparation in pediatric patients.

Photobiomodulation (PBMT) and antimicrobial photodynamic therapy (aPDT) in oral manifestations of patients infected by Sars-CoV-2: systematic review and meta-analysis.

Background: In 2019, a viral and respiratory pathology called COVID-19 emerged in Wuhan, China, and spread to other continents. Its main symptoms include fever, cough, dyspnea, myalgia, anorexia and respiratory distress in the most severe cases, which can lead to death. Furthermore, manifestations in the oral cavity such as ageusia and dysgeusia, as well as lesions in other regions of the oral cavity, can be observed. Main body: This systematic review and meta-analysis aimed to critically assess the clinical evidence on the use of photobiomodulation (PBMT) and antimicrobial photodynamic therapy (aPDT) for the treatment of oral lesions in patients infected with Sars-Cov-2. The literature extracted from electronic databases such as PubMed, Medline, CINAHL, and Google Scholar was screened for eligibility, and relevant articles were included. The review is limited to manuscripts published in English, Spanish and Portuguese language between December 2019 and October 2021. A total of 5 articles with 11 cases retracting PBMT and aPDT as therapeutic strategies for the regression of oral lesions and painful symptoms. The results show favoring the associated use of PBMT with aPDT (P = 0.004), and the isolated use of PBMT with the result of significant "P = 0.005" and good confidence interval (7.18, 39.20) in ulcerative lesions, herpetic, aphthous, erythematous, petechiae and necrotic areas. Conclusions: PBMT and aPDT could be effective in the treatment of oral lesions of patients infected with Sars-Cov-2 in a short period of time; however, more long-term randomized clinical trials studies are needed to define the therapeutic strategy.