Influence of Er:YAG laser irradiation on surface properties of Ti-6Al-4V machined and hydroxyapatite coated.

Surface treatment by laser irradiation can change the topography of titanium; however, little is known about the changes it causes when applied to other coatings. This study aimed to evaluate the influence of Er:YAG laser irradiation on the surface properties of titanium-aluminum-vanadium (Ti-6Al-4V) discs. Four Ti-6Al-4V surfaces were evaluated (n = 10): CON-control, machined without surface treatment; LT-machined + laser treatment; HA-hydroxyapatite coating; and LT-HA-hydroxyapatite coating + laser treatment. For the laser treatment, an Er:YAG laser with a wavelength of 2940 nm, a frequency of 10 Hz, and an energy density of 12.8 J/cm2 was used. The morphology of the coating was investigated by scanning electron microscopy and the surface composition by energy-dispersive X-ray spectroscopy. The influence of laser irradiation treatment on roughness and wettability was also evaluated. The Er:YAG laser promoted a significant reduction in the roughness Sa (p < 0.05) and in the contact angle (p = 0.002) of the LT surface compared to the CON surface. On the LT-HA surface, a significant decrease in roughness was observed only for the Rz parameter (p = 0.015) and an increase in the contact angle (p < 0.001) compared to the HA surface. The use of the Er:YAG laser with the evaluated parameters decreased the surface roughness and improved the wetting capacity of machined without surface treatment. In the group with hydroxyapatite coating, the laser influenced the surface roughness only for the parameter Rz and reduced their wetting capacity.

Mechanical performance of 3-dimensionally printed resins compared with conventional and milled resins for the manufacture of occlusal devices: A systematic review.

STATEMENT OF PROBLEM: Digital methods for manufacturing occlusal devices provide advantages over conventional techniques, but information about the mechanical properties of 3-dimensionally (3D) printed resins is scarce. PURPOSE: The purpose of this systematic review was to evaluate the literature to determine whether 3D-printed resins for occlusal devices present satisfactory mechanical performance when compared with milled and conventional heat polymerized and autopolymerized resins. MATERIAL AND METHODS: This systematic review followed the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol and was registered in the Open Science Framework. The search strategy was applied without restriction of time and language to Embase, PubMed, Scopus, Science Direct, and Web of Science databases, and to the nonpeer-reviewed literature in ProQuest and Google Scholar. The selection process was conducted independently in 2 stages by 2 reviewers according to the eligibility criteria. The risk of bias was analyzed by using a checklist of important parameters to be considered. The systematic review considered the population, intervention, comparison, outcome, studies (PICOS) format, where population was resins for 3D printing of occlusal devices, intervention was inherent characteristics of the resin, comparison was conventional heat polymerized, autopolymerized, and milled resins, outcome was mechanical performance, and studies were in vitro experimental studies. RESULTS: A total of 1430 articles were found with the search strategy. After removing 182 duplicates found in Rayyan, the title and abstract of 1248 articles were evaluated, of which 37 articles were screened from the databases, 23 were selected for full reading, and 6 met the eligibility criteria and were included in this review; 1 had a low risk of bias and 5 had a moderate risk. An additional search of the reference list of included articles did not result in the inclusion of any articles. A quantitative meta-analysis could not be performed because of the heterogeneity of the included studies regarding the type of resin used and the method for evaluating mechanical performance. CONCLUSIONS: Resins for 3D printing had satisfactory mechanical performance for interocclusal devices when compared with conventional heat polymerized and autopolymerized resins, except for hardness. Milled resins were better than 3D-printed resins in hardness, wear resistance, flexural strength, flexural modulus, and fracture resistance when printing angle and thickness were not considered. Further development is needed in terms of printing techniques and chemical composition, as they are important for optimal mechanical properties and clinical performance.

Assessment of neuromuscular fatigue through frequency analysis of the electromyographic signal of control participants and those with temporomandibular dysfunction treated with resilient or hard occlusal devices.

STATEMENT OF PROBLEM: Muscle hyperactivity that leads to neuromuscular fatigue can be evaluated by electromyography. Whether treatment with occlusal devices can restore neuromuscular balance to patients with temporomandibular disorders (TMDs) is unclear. PURPOSE: The purpose of this clinical study was to evaluate neuromuscular fatigue by analyzing the frequency of the electromyographic signal of the masseter and anterior temporalis muscles on both sides in healthy participants and those with TMD treated with a resilient or hard occlusal device. MATERIAL AND METHODS: One hundred asymptomatic participants and 30 with TMD were divided into 2 groups: treated with a hard device or treated with a resilient device. All underwent electromyographic examination before and after treatment with the occlusal devices. RESULTS: In both groups, the results showed statistically significant differences (P<.01) when the fatigue rate before and after treatment with an occlusal device was compared. CONCLUSIONS: Treatment with both types of occlusal device was efficient in reducing the rate of neuromuscular fatigue in patients with TMDs.

Effect of nanomaterial incorporation on the mechanical and microbiological properties of dental porcelain.

STATEMENT OF PROBLEM: Dental porcelain restorations are subject to biological failures related to secondary caries and periodontal disease leading to prosthesis replacement. PURPOSE: The purpose of this in vitro study was to explore the microbiological and mechanical properties of dental porcelain incorporated with different percentages of silver vanadate (ß-AgVO3) through microbiological analysis, roughness tests, and the Vickers microhardness test. MATERIAL AND METHODS: IPS InLine porcelain specimens were made by using a cylindrical Teflon matrix in the dimensions of 8×2 mm. For the control group, the porcelain was manipulated according to the manufacturer's instructions. The groups incorporating the nanomaterial were prepared with 2.5%, 5%, and 10% of ß-AgVO3, which was added proportionally by mass to the porcelain powder. In vitro microbiologic analysis, roughness tests, and the Vickers microhardness test were performed. RESULTS: Against Streptococcus mutans, the control group showed no inhibition halo (0 mm). All groups with AgVO3 showed a zone of inhibition, the highest for the group with 10% (30 mm) and then the groups with 2.5% (9 mm) and 5% (17 mm). For Vickers microhardness, no statistically significant difference (P<.05) was observed between the evaluated groups. The group with 10% of AgVO3 had the highest mean roughness and was statistically different (P<.001) from the other groups. CONCLUSIONS: Adding ß-AgVO3 to dental porcelain demonstrated antimicrobial effectiveness at all concentrations (2.5%, 5%, and 10%), with no effect on Vickers microhardness. The 10% group had higher roughness than the other groups.

Efficacy of acupuncture on craniomandibular myofascial pain in temporomandibular disorder patients: A systematic review.

Background: This systematic review aimed to answer the question, "What is the efficacy of acupuncture treatment in patients with temporomandibular disorder (TMD) with myofascial pain?". Data sources and study selection: This study followed PRISMA guidelines and was registered in PROSPERO. The electronic search strategy was applied to the Scopus, PubMed, Embase, and Science Direct databases. As inclusion criteria, were selected randomized clinical articles that evaluated patients with myofascial pain symptoms treated by acupuncture without the restriction of time and language. Results: The search in the databases resulted in 286 articles, after removing the duplicates 251 were analyzed by title and abstract. Twenty were selected for full reading and 10 were included in the systematic review. The studies evaluated acupuncture treatments by puncture and laser, auriculotherapy by puncture and laser, and an occlusal device for treating myofascial TMD. Conclusions: Comparing acupuncture with placebo acupuncture, it was observed that it is effective for subjective pain relief and palpation of orofacial structures with immediate results; it should be noted that there is still no specific protocol and that the duration of treatment must be personalized. When comparing it with the occlusal device, the associated treatment has enhanced the results. Future studies are suggested by the current literature gap that prevents the determination of clinical guidelines for effective acupuncture treatment in TMD patients with myofascial pain. Practical implications: Laser and needle puncture acupuncture treatment and laser and needle puncture auriculotherapy have shown favorable results in short-term myofascial pain relief. The need for long-term studies to assess benefits and reduce possible biases is highlighted. Clinical trial registry name: PROSPERO (CRD42021271505).

Malaria as a disease and as a cultural perspective in Carlos Chagas' and Mário de Andrade's travels to the Amazon. / Malária como doença e perspectiva cultural nas viagens de Carlos Chagas e Mário de Andrade à Amazônia.

Two journeys have had an important bearing on social thought regarding the Amazon: Carlos Chagas', from 1912 to 1913, and Mário de Andrade's, in 1927. The article examines how their travel experiences influenced these two men's views and interpretations of the relation between malaria and the project to bring civilization to the tropics. In Chagas' texts, wonderment is the category that organizes his perception of the Amazon region, evinced in the idea that the pathology of the tropics challenges established knowledge of the disease. Empathy, on the other hand, is the explanatory key to understanding Mário de Andrade's critical outlook, which entails the valorization of forms of sociability, beliefs, and popular manifestations in the region, including those related to malaria.

Reasons for the fatigue of ball attachments and their O-rings: A systematic review.

The ball attachments and their O-rings used for the retention and stabilization of overdentures showed a decrease in retention as the number of cycles increased. This fact resulted in a decrease in the retention of the prosthesis. The purpose of this study was to evaluate the fatigue resistance of ball attachments through a systematic review. An electronic search was performed using the Cochrane Library, LILACS, PubMed, ScienceDirect, and Web of Science databases. The search was conducted based on the PICOS framework. The inclusion criteria involved in the search comprised research articles written in English and published between the years 2000 and 2020. In the final selection, 18 articles were included in the review. Most of these studies performed the fatigue retention tests using parallel implants without angles. However, some studies used different angles to analyze the fatigue retention values. With the passage of time, the wear results in deformation and, as a consequence, a decrease in the retention of most attachments, leading to treatment failure. The main factor to be considered is the loss of retention of these components and their low durability. The loss of retention is due to large extent to the materials used to manufacture the attachments and O-rings, the size and angulation of the implants, and the length of the prosthesis. Future research is needed to further elucidate the reasons for the failure of the attachments.

Effects of photobiomodulation on auriculotherapy points for sleep disorders, anxiety, and temporomandibular dysfunctions.

OBJECTIVE: The purpose of this study was to evaluatephotobiomodulation applied at auriculotherapy points forsleep disorder (SD) and anxiety related to temporomandibulardysfunction (TMD). METHODS: The study consisted of two groups of 20 participants: Auriculotherapy group (A) and Control Group(C). The participants responded to the RDC/TMD, Fletcher & Luckett questionnaires, and the Beck Anxiety Inventory to analyze TMD, SD, and anxiety before and after the treatment. RESULTS: The participants presented scores corresponding to mild to moderateanxiety (MDN = 17; CI = [13.16;22.31]) and after treatment, normalor non-existent anxiety (MDN = 9; CI = [8.76; 17.12]) (p = 0.005). There was no significant difference (p > 0.05) between the controland 20 auriculotherapy groups for TMD and SD. DISCUSSION: The results suggest that auriculotherapy was effective in the treatment of anxiety. However, it did not prove effective with the results of the SD and symptoms of TMD.

Association between depression and temporomandibular dysfunction in adults - a systematic review.

OBJECTIVE: To critically evaluate the literature and answer the question: "Is there an association between depression and temporomandibular disorder (TMD) in adults?" METHODS: The personalized search strategy was applied to PubMed, Embase, Web of Science, and Scopus databases. Articles were selected in two stages according to the eligibility criteria. The Joanna Briggs Institute (JBI) tool was used to analyze the risk of bias according to the type of study. RESULTS: The included articles presented a moderate risk of bias. Based on the studies, individuals with TMD have higher levels of depression compared to the control group. There is also a direct association in that individuals with depression are more susceptible to developing TMD. CONCLUSION: There is a probable association between depression and TMD in adults. However, more studies with high methodological quality are needed to confirm this finding.

Sleep parameters in patients with chronic hypersensitivity pneumonitis: a case-control study.

OBJECTIVE: To compare patients with chronic hypersensitivity pneumonitis (cHP) and controls with normal spirometry in terms of their sleep characteristics, as well as to establish the prevalence of obstructive sleep apnea (OSA) and nocturnal hypoxemia. Secondary objectives were to identify factors associated with OSA and nocturnal hypoxemia; to correlate nocturnal hypoxemia with the apnea-hypopnea index (AHI) and lung function, as well as with resting SpO2, awake SpO2, and SpO2 during exercise; and to evaluate the discriminatory power of sleep questionnaires to predict OSA. METHODS: A total of 40 patients with cHP (cases) were matched for sex, age, and BMI with 80 controls, the ratio of controls to cases therefore being = 2:1. The STOP-Bang questionnaire, the Epworth Sleepiness Scale (ESS), the Pittsburgh Sleep Quality Index, the Berlin questionnaire and the Neck circumference, obesity, Snoring, Age, and Sex (NoSAS) score were applied to all cases, and both groups underwent full-night polysomnography. RESULTS: The patients with cHP had longer sleep latency, lower sleep efficiency, a lower AHI, a lower respiratory disturbance index, fewer central apneas, fewer mixed apneas, and fewer hypopneas than did the controls. The patients with cHP had significantly lower nocturnal SpO2 values, the percentage of total sleep time spent below an SpO2 of 90% being higher than in controls (median = 4.2; IQR, 0.4-32.1 vs. median = 1.0; IQR, 0.1-5.8; p = 0.01). There were no significant differences between cases with and without OSA regarding the STOP-Bang questionnaire, NoSAS, and ESS scores. CONCLUSIONS: The prevalence of OSA in cHP patients (cases) was high, although not higher than that in controls with normal spirometry. In addition, cases had more hypoxemia during sleep than did controls. Our results suggest that sleep questionnaires do not have sufficient discriminatory power to identify OSA in cHP patients.

Epidemiological and clinical characteristics of COVID-19 in a Brazilian public hospital.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has become a major health concern worldwide. In that context, the understanding of epidemiological and clinical features associated with the disease and its severity is crucial for the establishment of strategies aimed at disease control and remedy. AIM: To describe epidemiological features, signs, symptoms, and laboratory findings among severely ill COVID-19 patients from an intensive care unit in northeastern Brazil as well as to evaluate predictor factors for disease outcomes. METHODS: This is a prospective single-center study that evaluated 115 patients admitted to the intensive care unit in a northeastern Brazilian hospital. RESULTS: The patients had a median age of 65.60 ± 15.78 years. Dyspnea was the most frequent symptom, affecting 73.9% of the patients, followed by cough (54.7%). Fever was reported in approximately one-third of patients and myalgia in 20.8% of the patients. At least two comorbidities were found in 41.7% of the patients, and hypertension was the most prevalent (57.3%). In addition, having two or more comorbidities was a predictor of mortality, and lower platelet count was positively associated with death. Nausea and vomiting were two symptoms that were predictors of death, and the presence of a cough was a protective factor. CONCLUSION: This is the first report of a negative correlation between cough and death in severely ill severe acute respiratory syndrome coronavirus 2-infected individuals. The associations between comorbidities, advanced age, and low platelet count and the outcomes of the infection were similar to the results of previous studies, highlighting the relevance of these features.

Evaluation of Vickers hardness of different types of acrylic denture base resins with and without glass fibre reinforcement.

OBJECTIVE: To evaluate the Vickers hardness of different acrylic resins for denture bases with and without the addition of glass fibres. BACKGROUND: It has been suggested that different polymerisation methods, as well as the addition of glass fibre (FV) might improve the hardness of acrylic. MATERIALS AND METHODS: Five types of acrylic resin were tested: Vipi Wave (VW), microwave polymerisation; Vipi Flash (VF), auto-polymerisation; Lucitone (LT), QC20 (QC) and Vipi Cril (VC), conventional heat-polymerisation, all with or without glass fibre reinforcement (GFR) and distributed into 10 groups (n = 12). Specimens were then submitted to Vickers hardness testing with a 25-g load for 30 s. All data were submitted to anova and Tukey's HSD test. RESULTS: A significant statistical difference was observed with regard to the polymerisation method and the GFR (p < 0.05). Without the GFR, the acrylic resin VC presented the highest hardness values, and VF and LT presented the lowest. In the presence of GFR, VC resin still presented the highest Vickers hardness values, and VF and QC presented the lowest. CONCLUSIONS: The acrylic resin VC and VW presented higher hardness values than VF and QC resins. Moreover, GFR increased the Vickers hardness of resins VW, VC and LT.

Low level laser therapy as an adjunctive technique in the management of temporomandibular disorders.

The purpose of this study was to assess the effect of low level laser therapy on subjects with intra-articular temporomandibular disorders (IA-TMD), and to quantify and compare severity of signs and symptoms before, during, and after the laser applications. The sample consisted of 45 subjects randomly divided into three groups (G) of 15 subjects each: G-I: 15 individuals with IA-TMD submitted to an energy dose of 52.5 J/cm2; G-II: dose of 105.0 J/cm2; and G-III: placebo group (0 J/cm2). In all groups, the applications were performed on condylar points on the masseter and anterior temporalis muscles. Two weekly sessions were held for five weeks, totaling 10 applications. The assessed variables were: mandibular movements and painful symptoms evoked by muscle palpation. These variables were measured before starting the study, then immediately after the first, fifth, and tenth laser application, and finally, 32 days after completing the applications. The results showed that there were statistically significant differences for G-I and G-II at the level of 1% between the doses, as well as between assessments. Therefore, it was concluded that the use of low level laser increased the mean mandibular range of motion and reduced painful symptoms in the groups that received effective treatment, which did not occur in the placebo group.

Effect of photobiomodulation treatment on pain control in patients with temporomandibular dysfunction disorder: systematic review.

OBJECTIVE: To critically evaluate the literature and answer the question, "How effective is photobiomodulation treatment on pain control in patients with TMJ disorder?". METHODS: PRISMA, PubMed, Web of Science, Scopus, and Embase databases were used for the personalized search strategy. For risk of bias, Rob 2.0 for randomized clinical trials and ROBINS-I for non-randomized clinical trials were used. RESULTS: Eighty-four articles were found and, after removing duplicates, seventy one studies were included for titles and abstracts. For a full reading, 30 articles were selected and, according to the eligibility criteria, 24 remained for qualitative analysis. The studies showed a low risk of bias. Due to the heterogeneity of the studies, it was not possible to perform a meta-analysis. CONCLUSION: Photobiomodulation is an effective adjunct for the treatment of temporomandibular disorders, being a less invasive approach, safe, low-cost, and without side effects.

Is there any association between sleep disorder and temporomandibular joint dysfunction in adults? - A systematic review.

OBJECTIVE: To answer the question, "Is there any association between sleep disorder and temporomandibular joint dysfunction (TMD) in adults?" METHODS: This study followed PRISMA guidelines and was registered in PROSPERO. As eligibility criteria, observational studies that evaluated the association between sleep disorder and TMD were included. Exclusion criteria included a) studies that evaluated sleep quality and not the association of sleep disorders with TMD, b) experimental studies, book chapters, conference proceedings, and systematic reviews. The Joanna Briggs Institute tool was used to assess the risk of bias. RESULTS: In the literature search, 3425 articles were found. After the exclusion of duplicates, 2752 were selected for reading the title and abstract, of which 26 were read in full, and 18 met eligibility criteria. CONCLUSION: The association of sleep bruxism with TMD is controversial. While, for obstructive sleep apnea, insomnia, snoring, and gastroesophageal reflux, the analyzed studies showed a positive association.

Relationship between temporomandibular dysfunctions, sleep disorders, and anxiety among dentistry students.

Introduction: This study aimed to evaluate the relationship between temporomandibular dysfunction (TMD), anxiety, and sleep disorder (DS) among dentistry students, relating the periods in which they are enrolled.Methods: The study consisted of 90 students: Group 1: 30 first-period students; Group 2: 30 fifth-period students; Group 3: 30 students from the ninth period. The participants responded to the RDC/TMD, Fletcher & Luckett questionnaires, and the Beck Anxiety Inventory to analyze symptoms of TMD, DS, and anxiety.Results: There was an association between TMD, DS, and the period studied. When related to moderate and severe anxiety, the group that had the highest incidence was Group 1 (first period students).Conclusion: The apprehension for what is new can influence the TMD and DS indices, while the greater concern for academic/professional performance can generate higher levels of anxiety.

Influence of ß-AgVO3 nanomaterial incorporation on mechanical and microbiological properties of dental porcelain.

OBJECTIVE: To explore the effect of adding different percentages of nanostructured silver vanadate decorated with silver nanoparticles (ß-AgVO3) to dental porcelains, evaluating the antimicrobial activity and the influence on the mechanical properties. METHODS: Thirty-six specimens were made, for each concentration, control group, 0.5%, 1%, 2.5% and 5%, using two commercial brands: IPS InLine and Noritake Cerabien ZR. For the analysis of mechanical properties, the Vickers microhardness test and the roughness test were performed. For the antimicrobial analysis, the XTT and CFU assays were performed. RESULTS: There was a statistically significant difference between groups for mechanical and microbiological analyses. SIGNIFICANCE: The modification of dental porcelains, with the incorporation of ß-AgVO3, influenced the mechanical properties of the material and demonstrated antimicrobial activity at certain concentrations.

Incorporation of a ß-AgVO3 Semiconductor in Resin Cement: Evaluation of Mechanical Properties and Antibacterial Efficacy.

PURPOSE: This in vitro study aimed to investigate the effect of incorporating the semiconductor nanostructured silver vanadate decorated with silver nanoparticles (ß-AgVO3) in a dual-cure resin cement on the degree of conversion (DC), microhardness, roughness, color, adhesion properties before and after artificial aging, and antimicrobial efficacy. MATERIAL AND METHODS: Three test groups were established: control (without ß-AgVO3), with the incorporation of 2.5% and 5% (by weight) of ß-AgVO3 in dual-cure resin cement (Allcem, FGM). The degree of conversion was measured using Fourier transform infrared spectroscopy (FTIR). To evaluate roughness (n = 10), microhardness (n = 10), color (n = 10), and to perform agar disk diffusion (n = 8), disks of 6-mm diameter and 2-mm height were manufactured using the same concentrations. For the color and shear bond strength test (n = 6), orthodontic brackets (Morelli) were used, which were cemented to natural human enamel and evaluated before and after artificial aging via thermocycling at 5°C and 55°C for 1000 cycles. For color measurements, a portable spectrocolorimeter and the CIE-Lab method were used. Data were analyzed using Student's t-test, ANOVA, and Tukey's multiple comparisons with significance set at α = 0.05. RESULTS: Semiconductor incorporation did not influence the cements's DC. The incorporation of 2.5% and 5% of ß-AgVO3 resulted in a significant increase in Knoop microhardness and surface roughness. Significant changes were observed in the color of the specimens when the semiconductor was incorporated. Adhesion after aging remained within the clinically recommended values in all groups, and antimicrobial activity was observed against Staphylococcus aureus, Streptococcus mutans, and Enterococcus faecalis at both concentrations tested. CONCLUSION: It is suggested to incorporate the semiconductor ß-AgVO3 in the dual-cure resin cement at both concentrations. Moreover, the physical-mechanical properties remained satisfactory for the proposed application.

Standardization of the electromyographic signal through the maximum isometric voluntary contraction.

The objective of this study was to analyze the electromyographic (EMG) data, before and after normalization. One hundred (100) normal subjects (with no signs and symptoms of temporomandibular disorders) participated in this study. A surface EMG of the masticatory muscles was performed. Two different tests were performed: maximum voluntary clench (MVC) on cotton rolls and MVC in intercuspal position. The normalization was done using the mean value of the EMG signal of the first examination. The coefficient of variation CV showed lower values for the standardized data. The standardization was effective in reducing the differences between records from the same subject and in different subjects.

Nanostructured silver vanadate decorated with silver particles and their applicability in dental materials: A scope review.

OBJECTIVES: The present study aims to evaluate which studies evaluated the effectiveness of incorporating silver vanadate into dental materials and to analyze the influence of this incorporation on antimicrobial activity and material properties. DATA: This review was led by the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) Checklist and the JBI Briggs Reviewers Manual to answer the following question:Does the nanostructured silver vanadate decorate with silver particles present anti-microbial activity when incorporated into dental materials without altering its mechanical properties? SOURCE: An electronic search without restriction on the dates or languages was performed in PubMed/MEDLINE, Web of Science, Lilacs, Scopus, and Embase up until 2020. The search was specified and limited to the use of the words "nanostructured silver vanadate" in double quotation marks. STUDY SELECTION: The initial search resulted in 55 articles. After an initial assessment and careful reading, 15 studies published between 2014 and 2020 were included in this review. CONCLUSIONS: With the present scope review, it was possible to observe the good interaction between AgVO3 and dental materials and have a clarity that it is possible to use them in different types of materials in order to reduce the probability of infections resulting from the biofilm that is installed in them.