Brazilian dentist's knowledge of minimum intervention dentistry for caries management: application of a developed knowledge scale (MIDDeC-KS) and evaluation of its psychometric properties.

AIM: To assess the knowledge of Brazilian dentists about Minimum Intervention (MI) using a Minimum Intervention Dentistry to Dental Caries-Knowledge Scale (MIDDeC-KS) and evaluate its psychometric properties. MATERIALS AND METHODS: An online scale was developed to evaluate dentists' knowledge about MI. The higher the score, the greater the knowledge and vice versa. A preliminary study was carried out with 143 dentists to validate the MIDDeC-KS. For psychometric properties analysis, convergent and discriminant validity, test-retest reliability, and internal consistency of the instrument were assessed. After validation, MIDDeC-KS was applied to a representative sample of Brazilian dentists. T test for independent samples, Chi-square, and/or ANOVA one-way tests were applied. RESULTS: The MIDDeC-KS convergent (Spearman's = 0.48) and discriminant (P = 0.001) validity and reliability (ICC = 0.85, α = 0.72 and ω = 0.74) were proved. The participants (n = 637) obtained an overall mean score of 7.4 ± 2.5. The sample was mainly composed of females (P < 0.01), who graduated over 10 years prior (P = 0.02), from public colleges (P < 0.01), and most were pediatric dentists (38.2%). The highest and lowest scores were reached by pediatric dentists (9.2 ± 1.6) and bucomaxillofacial professionals (3.1 ± 2.1), respectively. Brazilian dentists demonstrated more knowledge about diet, biofilm, and topical fluoride control (84.3%), while the Hall technique (31.9%), resin infiltrant (47.6%), and chemical mechanical caries removal (48.4%) were the least known MI techniques. CONCLUSION: Brazilian dentists demonstrated more knowledge about preventive measures and less about more recent protocols, such as the Hall technique, resin infiltrant, and chemical mechanical caries tissue removal. Sufficient psychometric evidence of the MIDDeC-KS was found. CLINICAL RELEVANCE: Identify dentist's knowledge about MI.

Occurrence of bisphosphonate-associated osteonecrosis of the jaws in individuals with rheumatoid arthritis - a systematic review.

BACKGROUND: To access the occurrence of bisphosphonate-associated osteonecrosis of the jaw (BAONJ) in individuals with rheumatoid arthritis (RA). MATERIAL AND METHODS: Observational studies that evaluated the occurrence of BAONJ in individuals with RA (BAONJ-RA) were considered for inclusion. Electronic searches were performed up to December 2022 in six databases and in the grey literature. The study selection, data extraction, and quality assessment of the included studies according to the Joanna Briggs Institute Critical Appraisal Checklists was performed. The certainty of evidence was evaluated using the GRADE approach. RESULTS: Five studies were included three cohort and two cross-sectional. The sample size of subjects with RA ranged from 16 to 3201. Together, the studies presented 36 cases of BAONJ-RA. Prevalence of BAONJ-RA ranged from 0.094% to 56.25%. The incidence ranged from 0.4% to 2.21. Women between the 6th and 8th decade of life were the most affected. Alendronate (n=5) and zoledronic acid (n=9), orally and intravenously, respectively, were the most used bisphosphonates. The duration of bisphosphonates use ranged from 2.7 to 8 years. The certainty of evidence was very low. CONCLUSIONS: The occurrence of BAONJ-RA is low. However, the certainty of the evidence was very low for this outcome.

Assessment of the reliability of YouTube™ videos about zirconia crowns in pediatric dentistry.

PURPOSE: To evaluate the reliability of YouTube™ videos on zirconia crowns in pediatric dentistry. METHODS: On January 4, 2022, a search was performed using the term "pediatric zirconia crown". The first 100 videos on the subject were included. Non-English videos, duplicates, and off-topic videos were excluded. For each video, an examiner recorded the number of views, likes, comments, channel followers, upload date, duration, and category rating. Two examiners assessed the reliability of the information presented in the videos using DISCERN, a brief questionnaire and scale score used to assess in a valid and reliable way the quality of information on treatment choices for health problems. Descriptive and inferential analyses were performed (p < 0.05). RESULTS: Of the initial 100 videos, 72 were excluded because of language, duplication, and subject matter. The 28 remaining videos had an average of 3.5 comments, 8,896.18 channel followers, 5,614.00 views, 19.14 likes, and a duration of 840.32 s. The average view rate was 7.54 per day ± 10,206.81. There was a statistically significant difference between the number of views and comments (p < 0.001), likes and comments (p < 0.001), and likes and views (p = 0.006). According to the DISCERN, none of the videos received the maximum grade to be considered very good. Two were considered good, nine fair, fourteen poor, and three very poor. CONCLUSION: Given that the majority of YouTube™ videos currently available on zirconia crowns in pediatric dentistry were deemed unreliable according to the DISCERN questionnaire, caution should be exercised when using the information presented.

Worldwide research trends on the use of chemical-mechanical caries removal products over the years: a critical review.

BACKGROUND: Chemical-mechanical caries removal (CMCR) products are in constant evolution and were recommended during the COVID-19 pandemic as substitutes for conventional caries removal. AIM: Characterize the worldwide scientific literature about CMCR products, over the years, by means of a critical review. DESIGN: Electronic search was performed on Medline/PubMed, Scopus, Web of Science, Cochrane Library, Lilacs, and Embase up to November 2020. Year, journal, country of authors, and type of study were the data extracted from the retrieved studies. Additional data of the clinical studies and systematic reviews were investigated. RESULTS: 2221 records were identified, 397 selected. 2011-2020 period concentrates higher number of publications (n = 169), in the Journal of Dental Research (n = 51), developed in Brazil (n = 45) and India (n = 44). Most studies were in vitro (n = 211) and clinical trials (n = 101). Carisolv™ (n = 48) and Papacarie Duo Gel™ (n = 33) were the most used products, prescript in isolated usage (n = 101), and compared with drills (n = 77). CMCR were more studied in primary teeth (n = 78), receiving glass ionomer cement (GIC) (n = 51) as restorative material. The most evaluated outcomes were time spent (n = 48) and pain (n = 41). Clinical application of CMCR takes more time than other techniques, but can also reduce patient anxiety, pain, and need for anesthesia. CONCLUSION: In vitro and clinical studies with CMCR products have been increasing, mostly carried out in developing countries, evaluating Carisolv™ and Papacarie Duo Gel™. Clinical studies tend to evaluate the time spent and pain compared to drills for removing caries in primary teeth, posteriorly restored with GIC. CMCR clinical application reduces anxiety, pain, and need for anesthesia, despite increase treatments' time.

Does the addition of chlorhexidine to glass ionomer cements influence its antimicrobial effect and survival rate? A systematic review.

PURPOSE: To evaluate the influence of the addition of chlorhexidine on the antimicrobial effect and on the survival of restorations performed with glass ionomer cement. METHODS: Nine databases were used to search for randomized clinical trials that compared the survival rate and the antimicrobial effect of glass ionomer cement (GIC) restorations with and without the incorporation of chlorhexidine (CHX), without restrictions on year or language. Cochrane Collaboration's Risk of Bias 2 was used to assess the risk of bias. The GRADE approach was used to assess the certainty of evidence. RESULTS: From 593 studies found, seven met the inclusion criteria. The concentration of CHX varied between 0.5 and 2%. In general, the addition of CHX to GIC promoted reductions in Streptococcus mutans and Lactobacillus acidophilus burdens when compared to those without CHX. No study showed a difference in the survival of restorations between GIC with CHX and conventional GIC. Individual risk of bias varied from low to high and the certainty of evidence was classified as very low. CONCLUSIONS: Based on a very low level of certainty, the evidence suggests that the incorporation of CHX in GIC might improve the antimicrobial effects for a short time, in addition to having little influence on the survival of the restoration.

Worldwide trends on molar incisor and deciduous molar hypomineralisation research: a bibliometric analysis over a 19-year period.

AIM: To identify the worldwide trends in scientific evidence and gaps in knowledge regarding molar incisor hypomineralisation (MIH) and deciduous molar hypomineralisation/hypomineralised second primary molars (DMH/HSPM), exploring the contribution of authors and countries, possible etiological factors and proposed treatments, in order to guide future research in the area. METHODS: Searches were conducted in MEDLINE, Scopus, Web of Science, Cochrane Library, Lilacs/BBO, Embase and Google Scholar. Studies employing the terms MIH, DMH/HSPM and their linguistic variations were included. The following data were extracted: title, authors, year and journal of publication and first author's affiliation country. Studies were categorized according to topic, dentition, study design, etiological factors and types of treatments. Categories were analysed in relation to their distribution, co-occurrence, cross-correlation and/or autocorrelation. RESULTS: Five hundred and three studies were included. The most published authors were Manton D (n = 47), de Souza JF (n = 22) and Ghanim A (n = 22) and four main collaboration clusters have been identified. Most of the studies were conducted on permanent dentition (MIH) (87.4%); with observational design (57.2%). The "European Archives of Paediatric Dentistry" was the most published journal (13.3%) and a significant increase in the number of publications was observed in the last decade. MIH was most studied in relation to prevalence/incidence, systemic factors involved in its aetiology and treatment with composite restorations, while a gap in knowledge was observed for extraction and sealants. Less studies were published on DMH/HSPM and most of them evaluated risk factors or prevalence/incidence. The gap of knowledge was observed in relation to treatments and patient's quality of life. CONCLUSIONS: This bibliometric review provided a comprehensive overview of research in MIH and DMH/HSPM over the past 19 years. Within the limitations of the present study, the following conclusions can be drawn: global trends point to an increasing peak of scientific publication, especially in the last decade, while there is a shortage of clinical studies on treatments, mainly evaluating tooth extractions. Finally the multifactorial nature should be further explored, considering environmental and systemic factors together.

Treatment time, pain experience and acceptability of the technique for caries removal in primary teeth using the ART approach with or without Brix3000™ papain gel: a preliminary randomised controlled clinical trial.

PURPOSE: To compare the Atraumatic Restorative Treatment (ART) associated with Brix3000™ to ART considering treatment time, pain experienced, and acceptability to children. METHODS: This study was accepted in Research Ethics Committee in July 2019 (number 3469402). Healthy patients (n = 20) aged 3-9 years, with at least one primary molar with occlusal dentine caries without cusp involvement were randomly allocated to either the ART + Brix3000™ group or the ART-only group. The sample was characterised by sex, age, tooth location and caries experience. Time spent and pain experience scores were recorded at prophylaxis, caries removal and restoration. The pain experience (intense, moderate, or mild) was evaluated by the Face, Legs, Activity, Cry, Consolability-revised scale (FLACC-r). Acceptability was assessed by a five-point hedonic facial scale (dichotomised into 'like' and 'indifferent/dislike' bins) and by an open-question interview. Mann-Whitney, Chi-square, and Fisher's exact tests were applied to discern differences in time, pain/sample characterisation and acceptability, respectively. RESULTS: The ART + Brix3000™ group required 8.6 ± 3.1 min to remove caries tissue, whereas the ART group required only 4.8 ± 2.0 min (p = 0.03). The total time spent with treatments was 13.1 ± 4.0 min for ART + Brix3000™, and 9.8 ± 2.7 min for ART (p = 0.03). There was no difference in pain experience and acceptability found among the groups (p > 0.05). CONCLUSION: Although the ART + Brix3000™ technique demanded more treatment time than the ART alone, there were no differences in either pain experience or acceptability.

Does Addition of 10-MDP Monomer in Self-etch Adhesive Systems Improve the Clinical Performance of Noncarious Cervical Lesion Restorations? A Systematic Review and Meta-analysis.

BACKGROUND: Functional acidic monomers are able to chemically interact with hydroxyapatite, and this bond appears to be very stable. Therefore, this aspect of the 10-MDP molecule made it attractive and added to self-etch adhesives. OBJECTIVES: The objective of this Systematic Review (SR) and Meta-analysis (MA) was to determine whether systems with the 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) functional monomer in their formula showed better clinical performance in restorations placed in noncarious cervical lesions (NCCL) when compared to systems without it. The PROSPERO registration number of the MA is CRD42016050538. DATA AND SOURCES: An e-search was conducted through MEDLINE via PubMed, Cochrane Library, Scopus, Web of Science, OpenGrey, Clinical Trials, Current Controlled Trials, and EU Clinical Trials Register, and a search through the references of included studies was also performed. Randomized Controlled Clinical Trials, in which the effectiveness of self-etch adhesive systems, with or without the 10-MDP functional monomer for NCCL, was discussed, were included. Risk of bias was performed according to the Cochrane Collaboration tool, and the certainty of evidence was evaluated through GRADE. STUDY SELECTION: The data were grouped, heterogeneity (I2) was tested, and after duplicate removal, 4208 manuscripts were retrieved. From these, 11 studies were included in the qualitative analysis (risk of bias), with nine classified as low risk and two unclear. GRADE analysis detected moderate-to-high certainty of evidence, so the quantitative synthesis [Meta-analysis (MA)] was performed including the 11 studies. RESULTS AND CONCLUSION: There were no statistical differences in the clinical performance of restorations conducted using "with or without 10-MDP" adhesive types, for all evaluated criteria (p=0.05), with heterogeneity ranging from 0% to 53%. Thus, the presence of 10-MDP functional monomer did not influence the clinical performance of restorations placed in NCCL.

MTT versus other cell viability assays to evaluate the biocompatibility of root canal filling materials: a systematic review.

OBJECTIVES: This systematic review aimed to compare the cytotoxicity of root canal filling materials (RCFMs) assessed using tetrazolium salt-based tests (TSBT), including the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, with those obtained using other cell viability assays. METHODS: A search was performed on PubMed, Scopus, Web of Science and OpenGrey up to March 2019, followed by a manual search. According to the Participants, Exposure, Comparator and Outcomes (PECO) criteria, in vitro studies that evaluated the cytotoxic effect of RCFMss on animal and/or human cells through TSBT and at least one other viability assay were compared. The methodological quality of selected papers was assessed using ToxRTool® and SciRAP® . Data were analysed using Wilcoxon's signed-rank test for paired samples and linear weighting kappa. RESULTS: A total of 230 non-duplicated records were identified. After applying the eligibility criteria, 55 studies were selected for methodological evaluation, seven were selected by manual searching, 22 were excluded for methodological reasons, and 40 were included. A total of 410 comparisons were performed between TSBT and distinct cell viability tests (DCVT). MTT had moderate concordance with DCVT using human cells (n = 138 samples) (P = 0.507; k = 0.4225) and animal cells (n = 122 samples) (P = 0.124; k = 0.5775). XTT had good concordance using human (n = 110 samples) (P = 0.507; k = 0.6336) and animal cells (n = 12 samples) (P = 0.564; k = 0.6604). MTT, XTT, WST and MTS assays showed moderate concordance with DCVT (n = 410 samples) (P = 0.375; k = 0.5138) and complete agreement in 226 samples. DISCUSSION: The included studies had methodological heterogeneity that was minimized by the systematic review methodology. CONCLUSIONS: MTT and XTT do not cause over- or underestimation of cell viability during cytotoxicity screening of root canal filling materials, implying that these assays can be considered reliable for this purpose. Nonetheless, the development of protocols for the cytotoxic screening of these materials on 3D tissue-like cultures aiming to improve their predictability in the clinical scenario is suggested.

Does the Type of Solvent in Dental Adhesives Influence the Clinical Performance of Composite Restorations Placed in Noncarious Cervical Lesions? A Systematic Review and Meta-analysis.

CLINICAL RELEVANCE: According to the clinical and scientific evidence presented in this systematic review and meta-analysis, dental adhesives containing either organic solvent (acetone or alcohol) can be used to achieve similar clinical performance and longevity of composite restorations. SUMMARY: Objectives: This systematic review and meta-analysis compared the clinical performance and survival rates of composite restorations placed in noncarious cervical lesions (NCCLs) using dental adhesives containing acetone or alcohol-based solvents.Methods and Materials: PubMed, Scopus, Web of Science, Virtual Health Library (VHL) LILACS, Cochrane Library, OpenGrey, Clinical Trials, and Rebec were searched. MeSH terms, supplementary concepts, synonyms, and free keywords were used in the search strategy. All references were crosschecked by two independent investigators following the PICOS strategy (population, NCCLs; intervention, acetone-based bonding agent; comparison, alcohol-based bonding agent; outcome, clinical evaluation parameters and survival rates; study design, randomized controlled clinical trials). Cochrane Collaboration's tool was used to assess risk of bias, and two distinct meta-analyses were performed using the RevMan software. The prevalence of success and the total number of restorations for each group (acetone- or alcohol-based) were used to calculate the risk difference at a confidence interval of 95%. Random-effects models were applied, and heterogeneity was assessed using the I2 index in the pooled and subgrouped meta-analyses. The certainty of evidence was evaluated through the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.Results: A total of 7876 studies were retrieved, from which 27 studies were selected for the systematic review. Ten studies were classified as "low risk of bias" and included in the meta-analyses. Overall heterogeneity was not significant (I2 = 0.00%). The clinical performance of restorations placed with bonding agents based on both solvents for each of the available parameters presented no statistical significance for any of the meta-analyses (p>0.05).Conclusion: Scientific evidence suggests composite restorations placed with acetone or alcohol-based dental adhesives present similar clinical performance and survival rates in NCCLs.

Does tobacco smoking predispose to apical periodontitis and endodontic treatment need? A systematic review and meta-analysis.

BACKGROUND: Controversial findings exist in the literature regarding the association between tobacco smoking and development of apical periodontitis or need for root canal treatment, with some studies reporting an increase in the prevalence of these outcomes in smokers, whilst others reporting no association. AIM: To evaluate if there is scientific evidence to support an association between tobacco smoking and a greater prevalence of apical periodontitis and/or root canal treatments. DATA SOURCES: A systematic search was performed using MeSH terms and free terms in the PubMed, Scopus, Virtual Health Library (VHL), Cochrane library and Open Gray databases. STUDY ELIGIBILITY CRITERIA, PARTICIPANTS AND INTERVENTIONS: Observational studies that evaluated the association between smoking and the development or healing of periapical lesion and/or the prevalence of root canal treatment in humans were included. STUDY APPRAISAL AND SYNTHESIS METHODS: A quality assessment of included studies was performed, and the relevant information and findings were evaluated. A meta-analysis using nine included studies was performed through RevMan software, and the certainty of evidence was evaluated through GRADE. RESULTS: Fifteen studies were included, of which 10 were classified as low risk of bias, 4 were considered as moderate risk of bias and 1 as high risk of bias. Ten studies reported that smoking was associated with a greater prevalence of periapical periodontitis and/or root canal treatment. Five studies reported no association. Nine studies were included in the pooled meta-analysis, comprising two subgroups: apical periodontitis and root canal treatment. From these nine studies, eight studies were included in the apical periodontitis subgroup meta-analysis and demonstrated that this condition was significantly more prevalent in smokers when compared to the nonsmokers (odds ratio = 2.78[CI: 1.60, 4.85], P < 0.001; I2  = 79%; no adjusted odds ratio). Three studies were included in the root canal treatment subgroup meta-analysis and demonstrated an increased prevalence in smokers when compared to the nonsmokers (odds ratio = 2.73 [CI: 1.06, 2.83], P < 0.001; I2  = 72%; no adjusted odds ratio). The pooled meta-analysis demonstrated that smokers had twice the chance of having apical periodontitis and/or root canal treatment when compared to nonsmokers (odds ratio of 2.42 [CI: 1.59, 3.68], P < 0.01; I2  = 85%). The GRADE analysis demonstrated moderate certainty of evidence. LIMITATIONS: Several confounding factors were identified such as misinformation regarding the period of time subjects had smoked, as well as the frequency of smoking and the number of cigarettes consumed. No adjustment in odds ratio data for confounding was performed. CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS: This systematic review and meta-analysis indicate that tobacco smokers have an increased prevalence of periapical periodontitis and root canal treatments with moderate certainty of evidence.

Do Tooth- and Cavity-related Aspects of Noncarious Cervical Lesions Affect the Retention of Resin Composite Restorations in Adults? A Systematic Review and Meta-analysis.

PURPOSE: The purpose was to perform a systematic review and meta-analysis based on the following research question: do tooth- and cavity-related aspects of noncarious cervical lesions (NCCLs) affect the retention of composite restorations? METHODS: Randomized clinical trials (RCTs) that evaluated the retention rate of resin restorations in NCCLs were included for the identification and comparison of their characteristics. The search was conducted in PubMed and adapted for Scopus, Web of Science, Latin American and Caribbean Health Sciences Literature database (LILACS), Brazilian Library in Dentistry (BBO), Cochrane Library, and System for Information on Grey Literature in Europe (SIGLE) without restrictions until July 2018. Unpublished and ongoing trial registries were also searched. The Cochrane Collaboration tool was used for assessing risk of bias. The quality of the evidence was graded using the Grading of Recommendations: Assessment, Development and Evaluation. Using the random effects model, a meta-analysis was conducted for each aspect (arch distribution, tooth location, wear facets, dentin sclerosis, shape, size, depth, occluso-gingival distance, and margin location). RESULTS: We retrieved 6738 articles. After removal of duplicates and nonrelevant articles, 24 RCTs remained. The anterior tooth location favored the retention rates of restoration of NCCLs (relative risk [RR], 1.08; 95% confidence interval [CI], 1.00-1.16). The presence of wear facets is a risk factor for the retention of restorations (RR, 0.91; 95% CI, 0.83-0.99). The evidence was moderate for arch distribution and low or very low for all other factors because of heterogeneity, imprecision, and inconsistency. CONCLUSION: The tooth location and the presence of wear facets can affect the retention of composite resins in NCCLs.

Soft tissue assessment before and after mandibular advancement or setback surgery using three-dimensional images: systematic review and meta-analysis.

The aim of this systematic review was to evaluate the effects of mandibular advancement or setback surgery on the facial soft tissue assessed using three-dimensional images. An electronic search was performed in the MEDLINE, Cochrane Library, Scopus, Virtual Health Library (VHL), Web of Science, and OpenGrey databases. Inclusion criteria comprised studies that evaluated the soft tissues of adult patients before and after mandibular advancement or setback surgery using computed tomography or magnetic resonance imaging. The risk of bias was analyzed. A total of 3501 studies were retrieved. The titles and abstracts of 2071 studies were read and 2040 of them were excluded. Thirty-one articles were read in full and six fulfilled the eligibility criteria and were included. A meta-analysis was performed using three of these articles. The correlation was significant and strong in the chin area (r=0.876 and r=0.868) and moderate for the lower lip/lower incisor (r=0.690). The ratio for lower lip/infradentale was 78% and for Pog'/Pog was 98%. Due to the limited number of articles included, there is weak evidence to infer that changes in the facial soft tissue due to mandibular advancement or setback are significant, but changes in the lower lip tend to be smaller than changes in the chin area.

Three-dimensional changes to the upper airway after maxillomandibular advancement with counterclockwise rotation: a systematic review and meta-analysis.

The aim of this study was to evaluate the effect of counterclockwise (CCW) rotation and maxillomandibular advancement (MMA) on the upper airway space using three-dimensional images. An electronic search was performed in the PubMed, Cochrane Library, Scopus, Virtual Health Library, Web of Science, and OpenGrey databases (end date July 2016); a hand-search of primary study reference lists was also conducted. The inclusion criteria encompassed computed tomography evaluations of the upper airway spaces of adult patients undergoing orthognathic surgery with CCW rotation and MMA. The articles were evaluated for risk of bias with a tool for before-and-after studies. A meta-analysis was performed with the mean differences using a random-effects model. Heterogeneity was assessed with the Q-test and the I2 index. The meta-analysis revealed significant (P<0.001) increases in both the total airway volume (effect size of 6832mm3 and confidence interval of 5554-8109mm3) and the minimum axial area (effect size of 92mm2 and confidence interval of 70-113mm2). The heterogeneity was low in both comparisons (I2=38% and 7%, respectively). The technique of mandibular advancement with CCW rotation produced significant increases in the volumes and areas of the upper airway spaces.

Antibacterial properties and compressive strength of new one-step preparation silver nanoparticles in glass ionomer cements (NanoAg-GIC).

OBJECTIVES: This work aimed (1) to develop polyacid formulations by the one-step photoreduction of silver nanoparticles (AgNP) in a polyacrylate solution of conventional glass ionomer cement (GIC), imparting antibacterial activity; and (2) to evaluate handling and mechanical properties of experimental ionomers in comparison to a commercially available conventional GIC. METHODS: Formulations with increasing sub-stoichiometric amounts of AgNO3 were monitored during continuous UV light exposure by UV-vis spectroscopy and analyzed by transmission electron microscopy. The resulted synthesis of formulations containing small and disperse spherical nanoparticles (∼6 nm) were used to design the experimental nano-silver glass ionomer cements (NanoAg-GIC). The cements were characterized as to net setting time and compressive strength according to ISO 9917-1:2007 specifications. The antibacterial activity of these cements was assessed by Ag+ diffusion tests on nutritive agar plates (E. coli) and by MTT assay (S. mutans). RESULTS: The higher concentration of silver (0.50% by mass) in the matrix of NanoAg-GIC allowed viable net setting time and increased in 32% compressive strength of the experimental cement. All groups containing AgNP induced statistically significant E. coli growth inhibition zones (p-value <.05), indicating diffusion of Ag+ ions on the material surroundings. Metabolic activity of S. mutans grown on NanoAg-GIG with higher concentration of silver was significantly affected compared to control (p-value <.01). CONCLUSIONS: Silver nanoparticles one-step preparation in polyacrylate solution allowed the production of highly bioactive water-based cements within suitable parameters for clinical use and with large potential of dental and biomedical application.

Diallel and prediction (REML/BLUP) for yield components in intervarietal maize hybrids.

Genetic improvement is essential to achieve increments in maize (Zea mays L.) grain yield components. It may be obtained through crosses, which enable to exploit the effects of intervarietal heterosis, allelic complementarity, as well as gene actions and effects. This study estimated the components of variance and genetic parameters (REML/BLUP) of an intervarietal diallel to select and predict the best genotypes for maize yield components. The experimental design was randomized blocks containing 60 intervarietal maize hybrids arranged in three repetitions. They were obtained through intervarietal crosses and evaluated in a diallel scheme, where 14 open-pollinated varieties were designated as parentals. Thus, 10 crosses were performed for each hybrid combination to obtain the number of seeds necessary for the competition test. The measured traits were: grain volume relative index, the mass of one hundred grains, and grain yield. The male parents and the additive genetic fraction were determinants for grain volume relative index. Mass of one hundred grains and grain yield were defined by the specific combining ability, and female parents revealed low narrow sense heritability. The female parent Taquarão and male parent Argentino Amarelo presented the best general combining abilities for the measured traits. The specific combining abilities were expressed for crosses AL 25 x Dente de Ouro Roxo, AL 25 x BRS Pampeano, and Taquarão x Argentino Branco. Genetic estimates and predictions were consistent and applicable to breeding programs and could be applied in future quantitative genetic studies of maize.

How do geometry-related parameters influence the clinical performance of orthodontic mini-implants? A systematic review and meta-analysis.

The aim of this systematic review and meta-analysis was to investigate how parameters related to geometry influence the clinical performance of orthodontic mini-implants (MIs). Systematic searches were performed in electronic databases including MEDLINE, Scopus, Web of Science, Virtual Health Library, and Cochrane Library and reference lists up to March 2016. Eligibility criteria comprised clinical studies involving patients who received MIs for orthodontic anchorage, with data for categories of MI dimension, shape, and thread design and insertion site, and evaluated by assessment of primary and secondary stability. Study selection, data extraction, quality assessment, and a meta-analysis were carried out. Twenty-seven studies were included in the qualitative synthesis: five randomized, eight prospective, and 14 retrospective clinical studies. One study with a serious risk of bias was later excluded. Medium and short MIs (1.4-1.9mm diameter and 5-8mm length) presented the highest success rates (0.87, 95% CI 0.80-0.92). A maximum insertion torque of 13.28Ncm (standard error 0.34) was observed for tapered self-drilling MIs in the mandible, whereas cylindrical MIs in the maxilla presented a maximum removal torque of 10.01Ncm (standard error 0.17). Moderate evidence indicates that the clinical performance of MIs is influenced by implant geometry parameters and is also related to properties of the insertion site. However, further research is necessary to support these associations.

Selection of candidate reference genes and validation for real-time PCR studies in rice plants exposed to low temperatures.

Rice is a cereal that presents a great ability to adapt to different soil and climate conditions. However, as it is a tropical crop with C3 metabolism, it performs better in warm temperatures with high solar radiation. Tolerance to stress caused by low temperatures is a highly complex process that involves various metabolic pathways and cellular compartments, resulting in general or specific effects on plant growth and development. In order to observe the true effect of a particular stress on genetic expression, reference genes need to be chosen for real-time PCRs, the expression levels of which should remain stable independent of the situation imposed. In this paper, the expression stability was evaluated of the actin 11 (ACT11), ubiquitin-conjugating enzyme 2 (UBC-E2), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), beta tubilin (ß-Tubulin), eukaryotic initiation factor 4α (eIF-4-α), eukaryotic initiation factor 1α (eIF-1-α), ubiquitin 10 (UBQ10), ubiquitin 5 (UBQ5), aquaporin (TIP41), and cyclophilin genes, in two rice genotypes cultivated in low temperature (13°C) conditions in vegetative stage (V4). The analysis material (leaves) was collected after 0, 6, 24, 48, and 72 h of exposure to the stress. In this study, the geNorm, BestKeeper, ΔCt, NormFinder, and RefFinder methods were used to evaluate the expression stability of the candidate reference genes. The results revealed that the most indicated genes for all the analysis methods were UBQ10 and UBQ5 for BRS Bojuru and BRS Pampa, respectively. On the other hand, the eIF-1-α gene presents the least expression stability and is not indicated for studies of rice plants subjected to low temperatures. The validation with the antioxidant system genes SODCc1-Cu/Zn, CATC, APX2, and GR2 confirmed the importance of using previously tested normalizing genes for adequate real-time PCR results.

Estimates of genetic parameters and genotypic values prediction in maize landrace populations by REML/BLUP procedure.

The REML/BLUP statistics are analyses that can be used as selective criteria in the routine of maize breeding programs. The present study aims to determine the genetic potential in crosses of landrace populations applying the REML/BLUP methodology, and to identify populations for the synthesis of new populations and intrapopulation selection for family farming systems, as well as genetic constitutions for use in maize breeding programs. Nine top cross hybrids obtained in the 2012/2013 harvest were evaluated along with their testator, the landraces used as parents, and four commercial hybrids, in a randomized block design, with information taken from the average of each plot. The evaluated traits were: leaf angle, number of ramifications of the tassel, spike insertion height, plant height, spike diameter, number of grains per spike, mass of grains per spike, spike mass, spike length, prolificity, mass of one hundred grains, and grain yield per plot. The data were analyzed using the Selegen-REML/BLUP software. The top cross hybrids Cateto Branco x Planalto, Amarelão x Planalto and the population Cateto Branco are ranked among the ten best crosses, simultaneously, for the traits: leaf angle, number of ramifications of the tassel, spike insertion height, and plant height (Cateto Branco x Planalto), and leaf angle, spike insertion height, and plant height (Amarelão x Planalto and Cateto Branco). The top cross hybrids Criolão x Planalto, Branco 8 Carreiras x Planalto, Caiano Rajado x Planalto, Amarelão x Planalto, Branco Roxo Índio x Planalto stand out for their high genotypic value of the individual BLUP mean components among the ten best genotypes for grain yield, and by combining three or more traits of interest together, being, for effects of selection, the most indicated.