cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.14287721
title: Knowledge about Coronavirus disease 19 (COVID-19) and its professional repercussions among Brazilian endodontists

description: Abstract The aim of this study was to assess Brazilian endodontists’ level of knowledge about the coronavirus disease (COVID-19) and examine its professional repercussions. The link to the online survey that was created for this study was shared with Brazilian endodontists through social networking applications. The questionnaire contained questions that pertained to COVID-19 and its impact on dental practice. The collected data were analyzed using t-test, chi-square analysis, and analysis of variance, and the level of significance was set at 0.05. A total of 2,135 participants responded to the questionnaire, and all five Brazilian regions were represented in the sample. A total of 98.50% of endodontists reported that dental procedures can transmit COVID-19. Complete social distancing was practiced by 96.68% of the participants, and approximately 25% knew someone who had COVID-19. Moreover, in their daily practice, 72.13% of them implemented biosecurity measures that are ineffective in preventing COVID-19. Furthermore, 91.7% of them reportedly suspended elective dental procedures. Only 55.69% of them reported that they performed only emergency procedures in their workplaces. Those who believed that COVID-19 cannot be transmitted during dental procedures were less knowledgeable about the symptoms of COVID-19 (p = 0.0095). Endodontists who believed that personal protective equipment cannot prevent contamination were more knowledgeable about the symptoms of COVID-19 than their counterparts (p = 0.0003). The participating Brazilian endodontists demonstrated adequate knowledge about the risk of contamination during dental procedures and the main symptoms of COVID-19. Only some professionals reported providing emergency dental care during the pandemic.
DOI: 10.6084/m9.figshare.14287719
title: Delay in head and neck cancer care during the COVID-19 pandemic and its impact on health outcomes

description: Abstract The coronavirus disease 2019 (COVID-19) outbreak has created unprecedent challenges for healthcare systems worldwide. Oncology services have been reorganized to decrease the risk of nosocomial acquisition of SARS-CoV-2, but changes in treatment pathways and follow-up cancer care can result in patients receiving suboptimal or delayed care. Herein, we describe a cross-sectional nested cohort study conducted to evaluate delays in care for patients with head and neck cancer (HNC) in post-treatment follow-up or palliative care during the COVID-19 pandemic in Northeast Brazil and its impact on health outcomes. Information was extracted from medical records and supplemented by telephone interviews. We compared the following health outcomes: self-perception of anxiety or sadness, fear of COVID-19 infection, cancer-related complications during social isolation, self-medication, diagnosis of COVID-19, and death between patients with and without delayed cancer care. The Mann-Whitney U test was used to compare distributions of continuous variables and the Fisher exact test was used for categorical variables. Thirty-one HNC patients were included in the study, and no case of confirmed SARS-CoV-2 was found. Delayed cancer care due to restriction in health services was reported in 58.1% of cases, and there was no report of telemedicine use during the COVID-19 outbreak. Cancer-related complications during the COVID-19 pandemic were described for most patients (67.7%) and included pain or discomfort, swelling, and dyspnea. Eight (25.8%) patients reported use of prescribed morphine or codeine to manage pain and six (19.4%) patients reported self-medication with over-the-counter (OTC) non-steroidal anti-inflammatory drugs (NSAIDs). We found an association between delayed HNC care and the use of self-medication (p = 0.028). This study indicated that patients with delayed HNC care during the COVID-19 outbreak are more likely to use self-medication with NSAIDs for pain management. Better strategies to follow HNC patients in socioeconomically disadvantaged communities need to be discussed and implemented.
DOI: 10.6084/m9.figshare.14287716
title: Color stability of a bulk-fill composite resin light-cured at different distances

description: Abstract The aim of this in vitro study was to evaluate the color stability of a bulk-fill (Filtek One Bulk Fill, 3M ESPE) and a conventional (Filtek Z350 XT, 3M ESPE) composite resin light-cured at different distances, before and after being submitted to staining with a coffee solution. Sixty specimens of each composite resin were prepared and light-cured at distances of 0, 2 and 4 mm, using a LED light-curing unit (Valo, Ultradent). The specimens were separated (n = 10) for immersion in either distilled water or coffee solution (10 minutes a day for 8 days) to stimulate staining. Color evaluations were performed before and after immersion in the solutions, according to CIELab (△Eab), CIEDE2000 (△E00) and the Whiteness Index for Dentistry (△WID). Kruskal Wallis and Dunn tests, Mann-Whitney tests and Wilcoxon test were applied (α = 5 %). The a* value for conventional composite resin showed a significant increase after immersion in coffee and distilled water (p &lt; 0.05). Both composite resins showed greater b* values when immersed in coffee than in distilled water, with no significant difference among the light-activation distances (p &gt; 0.05). There was no significant difference for L* among the light-activation distances; both resins showed significant decrease in L* after immersion in coffee (p &lt; 0.05). Color change (△Eab, △E00) and difference in whiteness (△WID) were higher for conventional resin when immersed in the coffee solution at all the light-activation distances. Conventional composite resin presented a higher staining value than bulk-fill composite resin, regardless of the light-activation distance.
DOI: 10.6084/m9.figshare.14287713
title: The effect of amoxicillin on dental enamel development in vivo

description: Abstract The exposure to amoxicillin has been associated with molar incisor hypomineralization. This study aimed to determine if amoxicillin disturbs the enamel mineralization in in vivo experiments. Fifteen pregnant rats were randomly assigned into three groups to received daily phosphatase-buffered saline or amoxicillin as either 100 or 500 mg/kg. Mice received treatment from day 13 of pregnancy to day 40 postnatal. After birth, the offsprings from each litter continued to receive the same treatment according to their respective group. Calcium (Ca) and phosphorus (P) content in the dental hard tissues were analyzed from 60 upper first molars and 60 upper incisors by the complexometric titration method and colorimetric analysis using a spectrophotometer at 680 nm, respectively. Lower incisors were analyzed by X-ray microtomography, it was measured the electron density of lingual and buccal enamel, and the enamel and dentin thickness. Differences in Ca and P content and electron density among the groups were analyzed by one-way ANOVA. There was no significant difference on enamel electron density and thickness among the groups (p &gt; 0.05). However, in incisors, the higher dose of amoxicillin decreased markedly the electron density in some rats. There were no statistically significant differences in Ca (p = 0.180) or P content (p = 0.054), although the higher dose of amoxicillin could affect the enamel in some animals. The amoxicillin did not significantly alter the enamel mineralization and thickness in rats.
DOI: 10.6084/m9.figshare.14287712
title: Self-reported dental treatment needs during the COVID-19 outbreak in Brazil: an infodemiological study

description: Abstract The aim of the present infodemiological study was to evaluate whether the COVID-19 outbreak has influenced the volume of content related to the dental treatment needs of Brazilian Twitter users to summarize the trends, and to identify the perceptions of the treatment needed. We collected tweets related to dental care needs of individuals exposed to the COVID-19 outbreak scenario between March 23 to May 4, 2020 and of those not exposed to the COVID-19 pandemic (unexposed group) on the same reported days of 2019 using the terms “dentista (dentist), dente (tooth), siso (third molar), and aparelho (orthodontic appliance).” Descriptive analysis was performed to provide summary statistics of the frequencies of tweets related to different dental treatment needs and also the differences in volume content between the years 2019 and 2020. Moreover, the data were analyzed by qualitative analysis using an inductive approach. A total of 1,763 tweets from 2020 and 1,339 tweets from 2019 were screened. Those tweets posted by non-Brazilian users, duplicates, and those unrelated to dental treatment needs were removed and, therefore 1,197 tweets from 2020 and 719 tweets from 2019 were selected. Content volume related to dental treatment needs greatly increased during the COVID-19 outbreak. Findings from the word cloud and content analysis suggest that dental pain, related or not to the third molar, and problems with orthodontic appliances were the topics most commonly related to dental treatment needs discussed during the COVID-19 outbreak, mainly conveying anxiety and distress. The volume of tweets related to dental treatment needs posted by Brazilian users increased during the COVID-19 outbreak and self-reported pain and urgencies were the most popular topics.
DOI: 10.6084/m9.figshare.14287711
title: Salivary profile of children with erosive tooth wear: a transversal study

description: Abstract The aim of the present transversal study was to evaluate the clinical and biochemical salivary parameters of children with and without erosive tooth wear (ETW). The study population was children aged 4 to 9 years. A trained and calibrated examiner (kappa value for intraexaminer reliability = 0.89) classified the children into ETW (n = 24) and control groups (n = 24), and applied the O’Brien index. The salivary flow rate was initially evaluated by stimulated sialometry (paraffin chewing). Afterwards, the collected saliva was submitted to biochemical analyses of pH, uric acid, total buffering capacity, ferric-reducing antioxidant power, reduced glutathione, calcium, and phosphorus. Among the ETW children, 20 (83%) had dental lesions restricted to enamel, and 4 (17%) presented lesions affecting both enamel and dentin. A statistically significant difference between the groups was obtained only for the pH values (t-test; p = 0.004), with averages of 7.31 and 7.56 for the control and the ETW groups, respectively. Considering the parameters evaluated in general, it is suggested that the salivary profile of children with ETW does not differ considerably from that of children without ETW. However, the pH mean value seems to be slightly higher in ETW children, but is still within the normal physiological range.
DOI: 10.6084/m9.figshare.14287709
title: Fracture resistance of extensive bulk-fill composite restorations after selective caries removal

description: Abstract This study evaluated the effect of selective carious tissue removal on the fracture strength and failure mode of composite restorations in molars presenting only the buccal cusps. Deep cavities were prepared on the occlusal surface, and the lingual cusps were removed. Carious lesions in the middle of the pulpal wall were artificially induced with acetic acid (pH = 4.5) for 35 days. The demineralized dentin was left intact or was completely removed prior to restoration with a bulk-fill composite (n = 10). Images of the specimens were obtained by optical coherence tomography (OCT) before and after the caries induction/removal. The mechanical resistance to fracture by axial compressive loading and the failure type and extension were determined. The pulpal wall/composite interface of the fractured specimens was analyzed by OCT. The data were analyzed for significance with t-tests (α = 0.05). The deepest cavities and a more frequent occurrence of pulpal exposure were observed more often for non-selective carious tissue removal. The protocol of carious tissue removal did not affect the fracture strength (p = 0.554). An increased occurrence of catastrophic failures involving the roots was observed for non-selective carious tissue removal. Some occurrences of restoration displacement or cracks throughout the resin-dentin were observed only for the selective carious tissue approach. Selective carious tissue removal is a feasible approach to extensively damaged teeth since it reduced the occurrence of pulpal exposure and root fractures, without compromising the fracture strength.
DOI: 10.6084/m9.figshare.14287707
title: Effect of dental caries and socioeconomic status on social capital throughout adolescence: a 6-year follow-up

description: Abstract The aim of the study was to investigate the influence of clinical and socioeconomic factors on social capital throughout adolescence. A cohort study was performed in 2012 (T1) with a random sample of 1,134 12-year-old adolescents from Santa Maria, Brazil. Questions on socioeconomic factors (maternal education, household income, household crowding) were answered by the parents. Clinicians evaluated their dental caries (decayed, missing, and filled status of permanent teeth) and gingival bleeding (using the Community Periodontal Index). Contextual variables including the mean income of the neighborhood in which the school was located were used (T1). The adolescents were revaluated in 2018 (T2) and answered questions regarding social capital (social trust, social control, empowerment, neighborhood security, and political effectiveness). A path analysis was used to test the relationship between the predictor variables (T1) and social capital (T2). A total of 768 adolescents were reevaluated at a 6-year follow-up (cohort retention rate of 67.7%). Most of the adolescents were girls, with a low household income, about 40% had caries experience (T1), and about 64% had high social capital (T2). The highest neighborhood’s mean income was related to a lower household income in T1 (p &lt; 0.01), and this was directly related to a low social capital in T2 (p = 0.04). Furthermore, caries experience at T1 was directly associated with low social capital at T2 (p = 0.03). Socioeconomic factors were also related to caries experience. Individuals who lived in neighborhoods with greater inequality such as families with a low household income and those with untreated dental caries in early adolescence, had a low social capital after follow-up.
DOI: 10.6084/m9.figshare.14287704
title: Effect of Silicon dioxide coating of acrylic resin surfaces on Candida albicans adhesion

description: Abstract Acrylic resin has been used in the manufacture of prostheses, however, in the oral cavity, this material starts to retain microorganisms capable of causing gingival inflammation due its porosities. The aim of this study was to evaluate the influence of the use of silicon dioxide as a coating layer applied onto acrylic resin, on the adhesion of Candida albicans (Ca). After the incubation period in Sabouraud Dextrose Broth, a total of 1 ml of the Ca suspension was added to plate wells, each well containing a specimen of acrylic resin. The adhesion ability of Ca on acrylic resin was determined by counting colonies. Three groups (n = 6) of acrylic resin were assessed: with polishing (RP); without polishing (RW); with polishing and coating layer of silicon dioxide (RPC). Ca deposited on the surface of the acrylic resin was also observed using Scanning Electron Microscopy (SEM). Statistical assessment by Kruskal-Wallis and Student-Newman-Keuls Method were done (α = 2%). There was significant difference among the groups. The RPC group showed the lowest growth, with an average of 5.59 Log CFU/cm 2 ; there was a statistically significant difference in relation to group RW, which presented a growth of 6.07 Log CFU/cm 2 and to group RP with 5.91 Log CFU/cm 2 (p &lt; 000.1). SEM images demonstrated that in the RP and RPC group, the surface of the resin had greater regularity, and smaller number of microorganisms. The application of silicon dioxide coating on acrylic resin appears to be a promising alternative, and its use can help in reducing the adhesion of Ca in prostheses.
DOI: 10.6084/m9.figshare.14287703
title: Immunohistochemical expression of DNA repair proteins in oral tongue and lower lip squamous cell carcinoma

description: Abstract The DNA repair system involves genes and proteins that are essential for the maintenance of genome integrity and the consequent control of various cellular processes. Alterations in these genes and proteins play a role in tumor development and progression and might be associated with prognosis. The aims of this study were to analyze the immunoexpression of two DNA repair proteins, XPF and XRCC1, in lower lip squamous cell carcinoma (LLSCC) and oral tongue squamous cell carcinoma (OTSCC), and to investigate possible associations with clinical and histopathological parameters. The immunohistochemical expression of XPF and XRCC1 was analyzed semi-quantitatively in 40 cases each of LLSCC and OTSCC. The chi-squared test or Fisher’s exact test, when appropriate, was used to investigate the association between expression of the proteins and clinicopathological characteristics. The cytoplasmic immunoexpression of XPF was high in OTSCC (95% of the cases analyzed) but low in LLSCC (52.5%). Among the clinicopathological parameters evaluated, a statistically significant association was observed between high nuclear expression of XRCC1 and the absence of regional lymph node metastasis in patients diagnosed with OTSCC (p=0.006). The high protein expression of XPF and XRCC1 in OTSCC and LLSCC suggests an important role in the development and progression of these tumors. Our study found an association between high nuclear expression of XRCC1 and the absence of loco-regional metastasis in cases diagnosed as OTSCC, suggesting a role of this protein in tumor progression.
DOI: 10.6084/m9.figshare.14287702
title: Mechanical properties and surface roughness of polymer-based materials containing DCPD particles

description: Abstract The purpose of this study was to synthesize dicalcium phosphate dihydrate (DCPD) particles functionalized with triethylene glycol dimethacrylate (TEGDMA) through different routes by varying the receptor solution: ammonium phosphate (AP groups) or calcium nitrate (CN groups) and the moment in which TEGDMA was incorporated: ab initio (ab) or at the end of dripping the solution (ap). Two syntheses were performed without adding TEGDMA (nf). The particles were characterized by X-ray diffractometry, true density (using a helium pycnometer), surface area, and scanning electron microscopy. A 20 vol% of DCPD particles from the D, E, and F groups was added to the resin matrix to determine the degree of conversion (DC), biaxial flexural strength (BFS), the flexural modulus (FM), and surface roughness after an abrasive challenge (RA). A group with silanized barium glass particles was tested as a control. The data were submitted to ANOVA/Tukey’s test (DC, BFS, and RA), and the Kruskal–Wallis test (FM) (alpha = 0.05). BFS values varied between 83 and 142 MPa, and the CN_ab group presented a similar value (123 MPa) to the control group. FM values varied between 3.6 and 8.7 GPa (CN_ab and CN_nf groups, respectively), with a significant difference found only between these groups. RA did not result in significant differences. The use of calcium nitrate solution as a receptor, together with ab initio functionalization formed particles with larger surface areas. Higher BFS values were observed for the material containing DCPD particles with a higher surface area. In general, the DC, FM, and RA values were not affected by the variables studied.
DOI: 10.6084/m9.figshare.14287700
title: Assessment of dentists’ awareness and knowledge levels on the Novel Coronavirus (COVID-19)

description: Abstract Coronavirus disease-2019 (COVID-19) is the most recent infectious disease that is spreading rapidly throughout the world. This study aimed to evaluate the knowledge and awareness levels of dentists on COVID-19. This survey study, consisting of 37 questions, was sent to dentists via an online link in the first two weeks of April 2020. The questionnaire consisted of questions related to the knowledge level of dentists on COVID-19 during the pandemic period. The knowledge level of dentists was assessed with a 24-point scoring, consisting of correct answers. A Chi-square test was used to compare qualitative data (p &lt; 0.05). A total of 267 dentists participated in this study, of which 51.7% were aged under 30 years, and 67% were women. The participants’ knowledge level means score was 19.03 ± 3.15. According to these results, 231 were determined (86.5%) as high knowledgeable. Positive associations between increased knowledge level and factors such as being a woman, working in a university hospital, and being informed outside the institution were determined. The knowledge level of the dentists working in Istanbul about the COVID-19 pandemic is quite high.
DOI: 10.6084/m9.figshare.14287697
title: Influence of acidic monomer concentration and application mode on the bond strength of experimental adhesives

description: Abstract The aim of this research was to evaluate the influence of MDP (10-methacryloyloxydecyl dihydrogen phosphate) concentration and application mode of experimental adhesives on microshear bond strength (μSBS) to dentin after storage in distilled water at 37°C for 24h and 6 months. Five experimental adhesives were prepared with: CQ, DABE, BHT, ethanol, HEMA, TEGDMA, Bis-EMA, UDMA, and Bis-GMA. Concentrations of 0 wt%, 3 wt%, 9 wt%, 12 wt% or 15 wt% of MDP were added to their composition. The adhesives were applied to flat dentin surfaces in etch-and-rinse or self-etching modes. Cylindrical molds filled with light-cured composite resin were placed above the dentin. The specimens were stored in distilled water at 37oC for 24h or 6 months and submitted to μSBS testing. The adhesives were also submitted to pH analysis. The data were analyzed by one-way ANOVA, three-way ANOVA and Tukey’s test (α = 5%). All the adhesives used in the etch-and-rinse mode showed significantly higher bond strength than the adhesives applied in the self-etching approach. The 9 wt% adhesive showed the highest bond strength values, and 3 wt% was most stable after storage. A strong negative correlation between MDP concentration and pH was observed. It was concluded that the formulations with low concentrations of MDP (up to 9 wt%) showed better results for bond strength and bond strength degradation over time.