Consumer food environments change over a 5-year period.

OBJECTIVE: Evaluate the 5-year changes in the consumers' food environment in the area of a health promotion service in Brazilian primary health care. Our hypothesis is that the consumers' food environment in the areas with primary healthcare services has changes that may favour healthy eating habits over time. DESIGN: Longitudinal study. SETTING: The territory around the primary healthcare services in Belo Horizonte, Minas Gerais, Brazil. PARTICIPANTS: All food stores and open-air food markets that sell fruits and vegetables around the primary healthcare services in 2013 (n 272) and in 2018 (n 265). RESULTS: Fruit diversity increased by 13·4 % (P < 0·001) and vegetables variety and quality by 16·1 % (P = 0·003) and 12·5 % (P < 0·001), respectively. Corn snacks showed an increase in availability (13·5 %; P = 0·002). The increase in advertising was observed for fruits and vegetables (34·6 %; P < 0·001) and ultra-processed foods (47·6 %; P < 0·001). Supermarkets showed an increase in the Healthy Food Store Index (three points; P < 0·001), while fruits and vegetables stores showed a decrease of one point in the index (P < 0·001). CONCLUSIONS: The unequal changes in the consumers' food environment according to the food stores types demonstrate the importance of food supply policies that promote a healthy environment and favour the maintenance of traditional healthy food retailers.

Protocol of Randomized Controlled Community Trial (RCCT) for obesity management in Brazilian primary health care.

BACKGROUND: Obesity is a chronic disease characterized by excess body fat and is a risk factor for other chronic non-communicable diseases. Its multifactorial and complex nature makes its management a challenge for health services. This manuscript presents an investigation protocol that aims to analyze the effectiveness of collective nutritional interventions for obesity management applicable to primary health care. METHODS: Randomized Controlled Community Trial (RCCT) in a representative sample of users of the Programa Academia de Saúde (PAS), in Belo Horizonte, Minas Gerais, Brazil, with obesity. The research consists of four phases: (1) Screening to identify the participants eligible for the nutritional interventions (individuals with obesity, readiness for change to lose body weight, and willingness and interest to participate in a group activity for six months or more); (2) Baseline to characterize the participants; (3) Implementation of collective nutritional interventions; (4) Reassessment of the participants. Participants in the control group (CG) will receive the usual health service care, and participants in the intervention group (IG) will participate in collective nutritional interventions based on Therapeutic Group 1 (TG1) or Therapeutic Group 2 (TG2) of the "Instructive of Collective Approach for the obesity management in SUS". DISCUSSION: The strengths of the study include its robust RCCT design, which allows for longitudinal analyses and is suitable for investigating causal hypotheses and applying strategies to improve adherence to interventions. Furthermore, the study included a representative sample of a public health service and aims to evaluate therapeutic proposals from the Brazilian Ministry of Health, which can contribute to implementation and extension in the national territory. TRIAL REGISTRATION: RBR-3vzsyqq and RBR-6pg682m.

Smooth muscle tumours of the uterus: MR imaging malignant predictive features-a 12-year analysis in a referral hospital in Portugal.

PURPOSE: To evaluate the magnetic resonance imaging (MRI) features that may help distinguish leiomyosarcomas from atypical leiomyomas (those presenting hyperintensity on T2-W images equal or superior to 50% compared to the myometrium). MATERIALS AND METHODS: The authors conducted a retrospective single-centre study that included a total of 57 women diagnosed with smooth muscle tumour of the uterus, who were evaluated with pelvic MRI, between January 2009 and March 2020. All cases had a histologically proven diagnosis (31 Atypical Leiomyomas-ALM; 26 Leiomyosarcomas-LMS). The MRI features evaluated in this study included: age at presentation, dimension, contours, intra-tumoral haemorrhagic areas, T2-WI heterogeneity, T2-WI dark areas, flow voids, cyst areas, necrosis, restriction on diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) values, signal intensity and heterogeneity after contrast administration in T1-WI, presence and location of unenhanced areas. The association between the MRI characteristics and the histological subtype was evaluated using Chi-Square and ANOVA tests. RESULTS: The MRI parameters that showed a statistically significance correlation with malignant histology and thus most strongly associated with LMS were found to be: irregular contours (p < 0.001), intra-tumoral haemorrhagic areas (p = 0.028), T2-WI dark areas (p = 0.016), high signal intensity after contrast administration (p = 0.005), necrosis (p = 0.001), central location for unenhanced areas (p = 0.026), and ADC value lower than 0.88 × 10-3 mm2/s (p = 0.002). CONCLUSION: With our work, we demonstrate the presence of seven MRI features that are statistically significant in differentiating between LMS and ALM.

Genomic Signatures of Divergent Ecological Strategies in a Recent Radiation of Neotropical Wild Cats.

Ecological differentiation among diverging species is an important component of the evolutionary process and can be investigated in rapid and recent radiations. Here, we use whole genome sequences of five species from the genus Leopardus, a recently diversified Neotropical lineage with species bearing distinctive morphological, ecological, and behavioral features, to investigate genome-wide diversity, comparative demographic history and signatures of positive selection. Our results show that divergent ecological strategies are reflected in genomic features, for example a generalist species shows historically larger effective population size and higher heterozygosity than habitat specialists. The demographic history of these cats seems to have been jointly driven by climate fluctuations and habitat specialization, with different ecological adaptations leading to distinct trajectories. Finally, a gene involved in vertebrate retinal neurogenesis (POU4F2) was found to be under positive selection in the margay, a cat with notoriously large eyes that are likely associated with its nocturnal and arboreal specializations.

Environmental opportunities facilitating cognitive development in preschoolers: development of a multicriteria index.

Access to environmental opportunities can favor children's learning and cognitive development. The objectives is to construct an index that synthesizes environmental learning opportunities for preschoolers considering the home environment and verify whether the index can predict preschoolers' cognitive development. A quantitative, cross-sectional, exploratory study was conducted with 51 preschoolers using a multi-attribute utility theory (MAUT). The criteria used for drawing up the index were supported by the literature and subdivided in Group A "Resources from the house" extracted from HOME Inventory including: (1) to have three or more puzzles; (2) have at least ten children's books; (3) be encouraged to learn the alphabet; (4) take the family out at least every 2 weeks. Group B "Screens" (5) caution with using television; (6) total screen time in day/minutes. Group C "Parental Schooling" (7) maternal and paternal education. Pearson correlation analyses and univariate linear regression were performed to verify the relationship between the established index with cognitive test results. The index correlated with the total score of the mini-mental state exam (MMC) and verbal fluency test (VF) in the category of total word production and word production without errors. Multicriteria index explained 18% of the VF (total word production), 19% of the VF (total production of words without errors) and 17% of the MMC. The present multicriteria index has potential application as it synthesizes the preschooler's environmental learning opportunities and predicts domains of child cognitive development.

Evolution of fruit and vegetable intake among health promotion service participants in a Brazilian metropolis: 48-month follow-up of a randomized controlled community trial.

OBJECTIVE: To assess longitudinal effects of a nutrition intervention on fruit and vegetable (F&V) intake among Primary Health Care (PHC) service participants in Belo Horizonte, Brazil. METHODS: Demographics and health data on 3414 PHC service participants were collected at baseline in 2013-2014. F&V intake was assessed at baseline, 12, 36, and 48 months until 2017-2018. Services were randomized to control (CG, usual care) or intervention (IG, usual care and a Transtheoretical Model-based intervention to increase F&V intake). We performed difference-in-differences (DiD) analysis to identify intervention effects on F&V intake, and sensitivity analyses of participants observed at all timepoints. RESULTS: Participants were mostly middle-aged, low-income women. Mean baseline intakes were 168.7 g of fruit, 202.0 g of vegetables, and 370.7 g of F&V, with lower fruit in the IG (164.1 g) than the CG (172.3 g). At 12 months, the intervention increased fruit intake in the IG and fruit and F&V intake among individuals with low baseline F&V intake. Fruit intake remained higher at 36 months in the IG. No effect on vegetable intake was identified. According to sensitivity analyses, effects on fruit intake among the complete sample did not remain significant at 36 months, and an effect on fruit intake at 36 months was identified among those with adequate baseline F&V intake. Reductions in F&V intake did not remain significant. CONCLUSIONS: At 12 months, a TTM-based intervention increased fruit intake in the overall sample, and fruit and F&V intake among individuals with low baseline intakes. Repeated interventions may be needed over time. TRIAL REGISTRATION NUMBER: RBR-9h7ckx.

Association between illness perception and clinical control, quality of life, physical activity, and psychosocial status in subjects with moderate to severe asthma: a cluster analysis.

Background: Illness perception (IP) is a psychosocial factor involved in several chronic diseases and is associated with relevant clinical outcomes. However, the relationship between IP and health-related quality of life (HRQoL), psychosocial status, and physical activity in daily life (PADL) in subjects with asthma is poorly understood.Objective: To identify groups of subjects with asthma based on their IPs and to assess their association with clinical control, HRQoL, psychosocial disturbances, and PADL.Methods: This cross-sectional study included 149 subjects with moderate to severe asthma. IP, anthropometric data, Asthma Control Questionnaire-7, Asthma Quality of Life Questionnaire, Hospital Anxiety and Depression Scale, PADL (accelerometry), and general self-efficacy (GSE) were assessed. Cluster analysis was performed to identify clusters with similar profiles and investigate their characteristics and differences. Pearson's correlation coefficient was used to test the associations between IP and other variables.Results: Statistical analyses identified two clusters of subjects with asthma based on IP. Cluster 1 presented worse IP in seven out of eight domains than Cluster 2. Cluster 1 had more negative consequences of the disease, worse understanding, and a high emotional representation of the disease than Cluster 2. Cluster 1 also had a greater extent of asthma symptoms, poor clinical control, worse HRQoL, and more symptoms of anxiety and depression. No difference between clusters was found for PADL or self-efficacy.Conclusion: Subjects with asthma who have worse IP have more negative symptoms, worse clinical control, HRQoL, and symptoms of anxiety and depression.

Increased physical activity reduces sleep disturbances in asthma: A randomized controlled trial.

BACKGROUND AND OBJECTIVE: Individuals with asthma are more likely to develop sleep-disordered breathing. Exercise training improves sleep; however, the effect of physical activity (PA) on improving sleep quality remains unknown. This study had two objectives: (i) to evaluate the effect of a behavioural intervention to increase physical activity in daily living (PADL) on sleep quality in adults with asthma; (ii) to verify the association between a change in sleep quality, quality of life, anxiety, depression and asthma symptoms. METHODS: This randomized controlled clinical trial included adults physically inactive with asthma. Participants were randomized into the control (CG; n = 25) and intervention groups (IG; n = 24). IG was submitted to a behavioural intervention to increase PADL, and CG received the usual care. Pre- and post-intervention assessments of sleep quality (by actigraphy and questionnaire), PADL level (by accelerometry), asthma control, health-related quality of life and anxiety and depression levels were conducted. RESULTS: Both groups were similar at baseline. After the intervention, IG increased daily steps and moderate to vigorous PA levels. IG also improved sleep efficiency and latency as well as increased asthma-symptom-free days compared to CG. In addition, a greater proportion of participants in the IG had improved sleep quality after the intervention. Lastly, IG presented clinical improvement in the asthma-related quality of life questionnaire and a reduction in anxiety symptoms. CONCLUSION: Our results demonstrate that a behavioural intervention can increase PA, enhance behavioural sleep quality, efficiency and quality of life and reduce asthma and anxiety symptoms.

A longitudinal analysis of the fluctuation of food stores in Belo Horizonte, Minas Gerais, Brazil.

BACKGROUND: Changes in food environments have the potential to affect consumption, nutritional status, and health, and understanding these changes is of utmost importance. This study, therefore, aimed to examine the fluctuation of food stores that sell fruits and vegetables over five years in the health promotion service area of Primary Health Care (PHC) in Belo Horizonte, Minas Gerais, Brazil. METHODS: This was an ecological study that used data from a food environment audit conducted in the realm of Brazilian PHC. Buffers of 1 mile (equivalent to 1600 m) were created around health promotion services to define food environments. All food stores and open-air food markets that sold fruits and vegetables (FV) within this buffer area were considered eligible. The data collection was performed during two periods: the baseline, in 2013, and after five years, in 2018. This study compares the fluctuation by the type of stores and according to the health vulnerability index (HVI). RESULTS: After 5 years, 35.2% of the stores were stable; 154 stores were closed, and 155 were opened. The stability was greater in low-vulnerability areas, and the fluctuation differed by type of store only for areas with high vulnerability. The number of supermarket decreased in high HVI territories; and local stores, showed greater stability when compared to specialized FV markets. CONCLUSIONS: The differences in store fluctuations according to the vulnerability of areas demonstrate the importance of food supply policies considering the local characteristics to reduce inequities of access to healthy foods.

Photobiomodulation, Transmucosal Laser Irradiation of Blood, or B complex as alternatives to treat Covid-19 Related Long-Term Taste Impairment: double-blind randomized clinical trial.

COVID-19 Related Long-Term Taste Impairment (CRLTTI) is a condition that can be expressed after COVID-19 contagion, lasting for months or even years, affecting the routine and quality of life of individuals. Participants expressing CRLTTI, with a minimum of 2 months, attested by PCR-RT test were assessed for taste and smell, and underwent experimental treatments in 6 distinct groups: Photobiomodulation (PBM) in tongue dorsum and lateral (660 nm, 808 nm, association of 660 and 808 nm), Transmucosal Laser Irradiation of Blood (TLIB)-ventral surface of tongue (660 nm), B complex supplementation, and Sham laser. No intergroup statistical differences were observed at the final evaluation, despite the tendencies of better results with PBM and TLIB observed. PBM, TLIB, and B complex might be treatment options in the management of CRLTTI, despite the lack of total remission of taste and smell perception after 8 sessions (PBM and TLIB) or 30 days of B complex supplementation.

Genetic population structure of Pseudoplatystoma corruscans (Siluriformes: Pimelodidae) and evidence of temporal variation in structure.

Surubim (Pseudoplatystoma corruscans, Pimelodidae) are migratory catfish native to the rivers in the La Plata and São Francisco basins. They are piscivores that attain considerable body sizes and are a valuable economic resource. Surubim exhibits extensive migrations during its life cycle that may affect the population structure at vast geographic scales. The authors examined the genetic diversity and population genetic structure of P. corruscans using microsatellite markers from a comprehensive sampling of 260 individuals from the Upper and Lower Paraná River. They identified two well-differentiated genetic clusters corresponding to a natural geographic barrier historically separating Upper and Lower Paraná regions. They also demonstrated temporal variation in population genetic structure at a site in Lower Paraná close to the confluence with the Paraguay River, most likely explained by the influx of migrant fishes at certain times of the year.

Association between executive functions and gross motor skills in overweight/obese and eutrophic preschoolers: cross-sectional study.

BACKGROUND: Preschool age (3-5 years old) is a crucial period for children to acquire gross motor skills and develop executive functions (EFs). However, the association between the qualitative gross motor skills and EFs remains unknown in preschoolers, especially among overweight and obese children. METHODS: This was a cross-sectional, exploratory, and quantitative study carried out on 49 preschool children, divided into two subgroups according to their body mass index (overweight/obese: 24; eutrophic [normal weight]: 25). The mean age was 4.59 years. More than half of the sample were boys (55%) and most of the mothers had completed high school (67%) and were class C socioeconomic level (63%). Gross motor skills were assessed using the Test of Gross Motor Development-2, while EFs were evaluated using Semantic verbal fluency (SVF), Tower of Hanoi (TH), Day/Night Stroop, and Delayed Gratification tests. Multiple linear regression models adjusted for sex, age, maternal education, socioeconomic status, quality of the home environment, and quality of the school environment using the stepwise method were executed, considering the cognitive tasks as independent variables and gross motor skills as dependent variable. RESULTS: The overweight/obese preschoolers showed worse locomotor skills than their eutrophic peers and below average gross motor quotient (GMQ). Overweight/obese girls performed worse in OC skills than boys with excess weight. SVF (number of errors) and TH (rule breaks) explained 57.8% of the variance in object control (OC) skills and 40.5% of the variance in GMQ (p < .05) in the overweight/obese children. Surprisingly, there was no significant association between any of the EF tasks and gross motor skills in the eutrophic children. CONCLUSION: A relationship between EF tasks (number of errors in SVF and rule breaks in TH) and gross motor skills (OC and GMQ) was demonstrated in the overweight/obese preschoolers, indicating that worse cognitive flexibility, working memory, planning, and problem solving are associated with worse gross motor skills in this population when compared to eutrophic children.

The Influence of Different Bleaching Protocols on Dentinal Enzymatic Activity: An In Vitro Study.

This study aimed to investigate matrix metalloproteinase (MMP) activity in human dentin using in-situ and gelatin zymography, after at-home and in-office bleaching, related to their clinical exposure times. Dentin specimens (n = 5) were treated with 35% hydrogen peroxide (50 min per session/4 sessions), 10% carbamide peroxide (180 min/21 sessions), or no treatment. All were subjected to in-situ zymography. Dentin slices were, subsequently, obtained, covered with fluorescein-conjugated gelatin, and examined with confocal laser-scanning microscopy. The fluorescence intensity was quantified and statistically analyzed using one-way ANOVA and Bonferroni tests (α = 0.05). Furthermore, gelatin zymography was performed on protein extracts obtained from dentin powder (N = 8 teeth), treated with hydrogen peroxide or carbamide peroxide, with different exposure times (10/50 min for hydrogen peroxide; 252/1260 min for carbamide peroxide). The results of the in-situ zymography showed no statistical differences between the bleached specimens and the control group, with a medium level of gelatinolytic activity expressed in the dentin tubules. The results of gelatin zymography showed an increased expression of pro-MMP-9 in carbamide peroxide groups. The expression of pro-MMP-2 decreased in all the experimental groups. The bleaching treatments performed on the enamel of sound teeth do not influence dentinal enzymatic activity. However, when unprotected dentin tissue is bleached, matrix metalloproteinases are more expressed, particularly when carbamide peroxide is used, proportional to the exposure time.

Identification of asthma phenotypes based on extrapulmonary treatable traits.

Asthma is a heterogeneous and complex disease, and a description of asthma phenotypes based on extrapulmonary treatable traits has not been previously reported.The objective of this study was to identify and characterise clusters based on clinical, functional, anthropometrical and psychological characteristics in participants with moderate-to-severe asthma.This was a cross-sectional multicentre study involving centres from Brazil and Australia. Participants (n=296) with moderate-to-severe asthma were consecutively recruited. Physical activity and sedentary time, clinical asthma control, anthropometric data, pulmonary function and psychological and health status were evaluated. Participants were classified by hierarchical cluster analysis and the clusters compared using ANOVA, Kruskal--Wallis and Chi-squared tests. Multiple logistic and linear regression models were performed to evaluate the association between variables.We identified four clusters: 1) participants with controlled asthma who were physically active; 2) participants with uncontrolled asthma who were physically inactive and more sedentary; 3) participants with uncontrolled asthma and low physical activity, who were also obese and experienced anxiety and/or depression symptoms; and 4) participants with very uncontrolled asthma who were physically inactive, more sedentary, obese and experienced anxiety and/or depression symptoms. Higher levels of sedentary time, female sex and anxiety symptoms were associated with increased odds of exacerbation risk, while being more active showed a protective factor for hospitalisation. Asthma control was associated with sex, the occurrence of exacerbation, physical activity and health status.Physical inactivity, obesity and symptoms of anxiety and/or depression were associated with worse asthma outcomes, and closely and inextricably associated with asthma control. This cluster analysis highlights the importance of assessing extrapulmonary traits to improve personalised management and outcomes for people with moderate and severe asthma.

Challenges for obesity management in a unified health system: the view of health professionals.

BACKGROUND: Obesity is an increasingly prevalent chronic condition. Its multiple causes and the complexity of its treatment pose challenges for health professionals. OBJECTIVE: To explore and describe the challenges for obesity management in the Brazilian Unified Health System according to health professionals. METHODS: An exploratory quantitative web-based study, carried out in 2018 with health professionals, developed from the first stage of a national project that aims to examine the management of obesity in Brazil. The questionnaire was self-applied. Invitations to participate in the research were sent by the Ministry of Health, Health Department of Minas Gerais and members of the research group. We collected data on sex, age, professional category, region and level of care. The challenges were investigated using a Likert scale and categorized into structure and work process. RESULTS: We evaluated 1323 professionals, of which about 45% were dietitians, 90.2% were women, and 83.1% self-reported working in primary health care. The main barriers cited included a high demand for curative and individual assistance, the presence of comorbidities, and the absence or insufficient access to instructional materials, professional qualification and lack of support. CONCLUSION: Obesity management is a critical challenge for all professionals. Barriers were related to the work process and structural aspects and reinforce the need to empower health teams. We propose that permanent education activities should be established, as well as the development of instructional materials that are applicable to routine work. Finally, the results may be used to develop policies and strategies to improve obesity management.

Dietary and nutrient intake among participants of a Brazilian health promotion programme: a cross-sectional study.

OBJECTIVE: Developing health promotion activities, aimed at healthy food intake, is essential for improving quality of life and reducing the prevalence of chronic diseases. Thus, the objective of this study is to describe both dietary and nutrient intake, according to length of participation in a health promotion service (Programa Academia da Saúde - PAS). DESIGN: A cross-sectional study was carried out with a representative sample of PAS units in vulnerable areas of the city. Dietary and nutrient intake were assessed, using the average of two 24-h recalls. Food was categorised according to the NOVA (a systematic grouping of all foods according to the nature, extent and purpose of the industrial processes they undergo) classification. The length of participation in PAS is presented in months and is then examined in tertiles for analysis. SETTING: Belo Horizonte - Brazil. PARTICIPANTS: 3372 adults (≥20 years). RESULTS: Users in the third tertile of PAS (24·4-61·6 months) experienced less energy intake, lipids and ultra-processed foods, and more culinary preparations, compared to others. Users in the second (10·1-24·3 months) and third tertiles of PAS had higher carbohydrate intake, Ca and vitamin C v those in the first tertile (0-10 months). CONCLUSIONS: Results suggest that greater participation in PAS can improve dietary and nutrient intake, showing its potential to promote healthy lifestyles, prevent chronic diseases and offer longitudinal health care.

Consumption of ultra-processed foods and nutritional profile in a health promotion service of primary care.

OBJECTIVE: Describing the consumption of ultra-processed foods (UPF) and their association with the nutritional profiles among users of a health promotion service in a Brazilian city. DESIGN: Cross-sectional study. SETTING: Public health promotion service of Primary Health Care in Belo Horizonte, Minas Gerais, Brazil. PARTICIPANTS: Totally, 3372 participants. RESULTS: UPF were found to contribute to 27·7 % of the diet's total energy. The highest consumption was associated with higher values for energy intake (1561·8 v. 1331·8 kcal/d; P < 0·01), energy density (1·7 v. 1·4 kcal/g; P < 0·01), total (32·5 v. 27·3 %; P < 0·01) and trans-fats (2·1 v. 1·2 %; P < 0·01) and Na (1001·6 v. 758·9 mg/1000 kcal; P < 0·01) and with lower values for proteins (14·9 v. 19·6 %; P < 0·01), mono-unsaturated fats (16·1 v. 20·1 %; P = 0·02), n-3 (0·9 v. 1·1 %; P < 0·01) and some vitamins and minerals when comparing individuals in the last quintile of energy contribution from UPF in relation to the first one. The prevalence rate of nutrient inadequacy aimed at preventing non-communicable diseases increased between 30 % and 100 % when compared with the values of the fifth to the first quintile of UPF consumption (P < 0·001). However, the participants had lower energy intake, energy density and Na and higher fibre consumption when compared to Brazilian population. CONCLUSIONS: Participants showed a high consumption of UPF, but also positive diet characteristics when compared with the national data. The results suggest the importance of health promotion services to promote healthy food and the need to include approaches to reduce UPF consumption.

In situ Effect of CO2 Laser (9.3 µm) Irradiation Combined with AmF/NaF/SnCl2 Solution in Prevention and Control of Erosive Tooth Wear in Human Enamel.

OBJECTIVES: This single-blind, controlled crossover in situ study aimed to evaluate the effect of CO2 laser (9.3 µm) irradiation combined with AmF/NaF/SnCl2 solution on prevention and control of erosive tooth wear (ETW) in human enamel. MATERIALS AND METHODS: Two trial conditions were analyzed, condition 1 as ETW prevention (sound tooth surface) and condition 2 as ETW control (in vitro initial erosive lesion). The experiment was conducted in 2 phases, one with and one without exposure to AmF/NaF/SnCl2 solution. Hundred and ninety-two samples of human enamel (3 × 3 × 1 mm) were randomly divided into 4 experimental groups for each condition: C, without treatment (negative control); F, AmF/NaF/SnCl2 solution (positive control); L, CO2 laser irradiation; and L + F, CO2 laser + AmF/NaF/SnCl2 solution. Twelve volunteers used a removable device, each containing 8 samples per phase. Ex vivo erosive challenges (4 × 5 min/day) and rinsing protocol (1 × 30 s/day) were performed. The surface loss was determined using optical profilometer (n = 12 per group), and the surface morphology was observed with scanning electron microscopy (n = 3). RESULTS: In condition 1, data were analyzed by one-way ANOVA and condition 2 by two-way repeated-measures ANOVA, both with Tukey post hoc tests (α = 5%). In condition 1, groups L (4.59 ± 2.95 µm) and L + F (1.58 ± 1.24 µm) showed significantly less surface loss in preventing ETW than groups C and F. In condition 2, in controlling the progression of ETW, L + F was the only group with no significant surface loss between initial erosive lesion (3.65 ± 0.16 µm) and after erosive challenge (4.99 ± 1.17 µm). CONCLUSIONS: CO2 9.3-µm laser application prevented and controlled ETW progression in human enamel, with greater efficiency when combined with AmF/NaF/SnCl2 solution application.

Influence of Er:YAG laser surface treatment on flexural and bond strengths to glass-infiltrated zirconia-reinforced ceramic.

To evaluate the effect of Er:YAG laser conditioning of a glass-infiltrated alumina-based zirconia-reinforced ceramic on its flexural strength and on bonding to a resin cement. Sixteen blocks (5 × 5 × 4 mm) and 50 discs (Ø 12 mm, 1 mm thickness) of In-Ceram Zirconia (ICZ) obtained from CAD-CAM blocks were infiltrated with glass. For the microtensile bond strength (µTBS) test, all blocks were treated with aluminum oxide (AOX) and divided into 4 groups (n = 4): G1 (AOX), no combined surface treatment; G2 (ROC), tribochemical silica-coating; G3 (EY200), Er:YAG laser 200 mJ/15 Hz; and G4 (EY250), Er:YAG laser 250 mJ/10 Hz. The ceramic blocks were silanated and cemented with a resin cement (Panavia F2.0/Kuraray) to composite resin blocks and subjected to the µTBS test. For the flexural strength evaluation, the discs were divided into 5 groups (n = 10) as described above, in addition to a control group (G5 - CTRL, mirror-polished without further treatment). Each surface treatment was submitted to qualitative evaluation under SEM. One-way ANOVA (α = 5%) revealed the highest bond strength value for EY200 with no significant difference from ROC. The groups AOX and EY250 showed similar µTBS values that were statistically lower than those of EY200. For flexural strength, ROC was the only group with significantly lower values when compared with the CTRL. The use of Er:YAG laser at 200 mJ/15 Hz can be considered an innovative and effective alternative for surface conditioning of ICZ since it did not reduce the flexural strength of the ceramic and improved the resin cement bond to this substrate.

Influence of biosafety materials of the laser output power.

Biosafety materials used in the correct handling of low power laser equipment may interfere on the power delivered at the target tissue and, possibly, on the effects on biological tissues. The aim of this study was to evaluate the interference of the use of polyvinyl chloride (PVC) and polyethylene (PEAD) protection materials on the output power of low power lasers. Two low power diode laser devices with different wavelengths (red and infrared) were used. For each wavelength, two protection materials and two evaluation times (before and after protection) were considered. The output power (mW) was measured with the tip positioned in close contact with the power meter receiver. Parametric statistical test, two-way ANOVA for repeated measures (protection material and time), was performed considering the level of significance of 5%. In respect to "time", all groups had the output power reduced after placing the protective material (p < 0.05). Comparing the protection materials, the PEAD showed a greater reduction in output power than the PVC for both red and infrared wavelengths. It was concluded that, among the biosafety materials tested, PVC is the most suitable for the protection of the tip of the low power lasers.