cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.14304809
title: Effect of Prior Application of Desensitizing Agent on the Teeth Submitted to In-Office Bleaching

description: Abstract This study aimed to quantify the penetration of hydrogen peroxide, color change evaluation, surface morphology, and composition after application of desensitizing agents before in-office bleaching. Fifty premolars were sectioned, an acetate buffer was placed in the pulp chamber and divided into five groups (n=10). In the positive control group, only the in-office bleaching gel was used, and in the negative control group, no treatment was used. Three different desensitizing agents were applied: Desensibilize KF2%® group; Mi Paste® group, and Desensibilize Nano-P® group. The bleaching procedure was carried out with 35% HP. The absorbance of the resulting solution was determined in a spectrophotometer. Color change was assessed by using a digital spectrophotometer. Four additional premolars were assigned to the same groups above for analysis under scanning electron microscope, as well as to evaluate the elemental composition with X-ray dispersive energy spectrometry. Data were subjected to ANOVA and Tukey's test (α=0.05). All products reduced the penetration of HP in the pulp chamber. Mi Paste and Nano P were the products that yielded the lowest HP penetration, which was similar to the negative control group (p&lt;0.001). No significant difference was detected in color change (p&lt;0.001). Concerning enamel morphology, the groups that were analyzed after bleaching were observed a greater deposition of desensitizing agents on the surface. The use of desensitizing agents before tooth bleaching seems to be an alternative to reduce adverse effects of the tooth.
DOI: 10.6084/m9.figshare.14304804
title: Overexpression of HIF-1α and Morphological Alterations in the Tongue of Rats Exposed To Secondhand Smoke

description: Abstract Smoking is a risk factor for serious health problems and is associated with several changes in the tissues of the oral cavity. The aim of this study was to evaluate the collagen percentage, mast cells density, intensity of immunolabeled cells by anti-HIF-1α in the musculature lingual of rats exposed to secondhand smoke. Twenty-seven female Wistar albino rats were divided into three groups: rats not exposed to tobacco smoke inhalation (Control group) (n=7); rats exposed to smoke inhalation for 30 days (TAB 30) (n=10); and rats exposed to smoke inhalation for 45 days (TAB 45) (n=10). Subsequently, the animals were submitted to euthanasia and removal of the tongue for histological and immunohistochemistry processing and analysis. In the groups TAB 30 and TAB 45 there were a lower percentage of collagen, a higher density of mast cells and a greater intensity of anti-HIF-1α immunolabeled cells compared to Control group. There was also a positive and significant correlation between the percentage of collagen and mast cell density. There was not significative difference between TAB 30 e TAB 45 in any of the parameters evaluated. Therefore, the exposure of rats to secondhand smoke for 45 days causes decrease in perimysial collagen fibers, increase in the number of mast cells and increase in the immunolabeling for HIF-1α in lingual muscle cells. The present study was the first to evaluate the percentage of collagen, mast cell density and immunostaining for HIF-1α in rat tongues exposed to tobacco smoke.
DOI: 10.6084/m9.figshare.14304803
title: Physical-Mechanical Properties of a Resin-Modified Calcium Silicate Material for Pulp Capping

description: Abstract The purpose of this study was to investigate and to compare the physical-mechanical properties of a resin-modified calcium silicate material (TheraCal LC), used for pulp-capping, to MTA (Angelus) and a calcium hydroxide cement (Dycal). Specimens of each material (n=12) were prepared in Teflon molds (3.58 mm x 3 mm) and measured before and after immersion in distilled water for 24 h and 30 days to evaluate the dimensional change. The same specimens were submitted to compressive strength test on a Universal Testing Machine (Instron) (1 mm/min). Root canals were filled with the cements (n=8), and after 24 h, the bond strength (push-out test) to dentin was also assessed on a Universal Testing Machine (1 mm/min). Eight additional specimens of TheraCal LC were prepared to evaluate the bond strength immediately after light curing. Data were analyzed using One-Way ANOVA, and Tukey or Bonferroni post hoc tests (p&lt;0.05). Percentage expansion of TheraCal LC was above the Specification No. 57 of ANSI/ADA, in both periods. The dimensional change for TheraCal LC was higher than MTA in 24 h and 30 days; and Dycal in 30 days (p&lt;0.05). TheraCal LC had higher compressive and bond strength to dentin in comparison with MTA and Dycal (p&lt;0.05). Although TheraCal LC expanded more than the ANSI/ADA recommendation, its compressive and push-out bond strength to dentin were satisfactory and superior to MTA and Dycal.
DOI: 10.6084/m9.figshare.14304800
title: Influence of Root Canal Preparation on Formation of Dentinal Microcracks: A Systematic Review

description: Abstract The effect of root canal preparation technique on microcrack initiation is a controversial issue. This systematic review aimed to assess the role of root canal preparation techniques with different kinematics (manual, rotary, reciprocating, adaptive, self-adjusting file) on microcrack initiation. In vitro and in situ studies comparing the influence of at least two different root canal preparation techniques on the initiation of dentin microcracks were searched in PubMed/MEDLINE and SCOPUS up to June 5, 2018 without language and period restriction. Two authors independently reviewed all identified titles and abstracts for eligibility. Tables were generated to summarize the included studies, and the included studies were assessed for bias. Fifty-four (n=54) articles met the eligibility criteria. The results were classified according to the method used for microcrack evaluation, and most studies that used micro-computed tomography showed no formation of new cracks after root canal preparation. In general, the instrumentation techniques induced microcrack formation when the methods were destructive, irrespective of kinematics. In relation to the apex region, when the preparation working length was set as the root canal length subtracted of 1 mm, the risk of microcrack initiation reduces. The majority of the included studies had low risk of bias for all assessed domains. Our results seem to indicate that the various root canal preparation techniques considered in this study will not cause damage to the dental structure when adequately employed and the proper methodology is applied.
DOI: 10.6084/m9.figshare.14304797
title: In Vitro Homeostasis of Rat Oral Epithelial Cell Cultures Following Withdrawal of Periodontal Pathogens

description: Abstract Inflammation of periodontal tissues is the consequence of interaction between periodontal pathogens and immune system. This is associated with increased expression of inflammatory cytokines, which may exert destructive effect to the periodontal tissues when released over long period. The aim of this study was to chronologically track the homeostasis of oral keratinocytes following removal of periodontal pathogens. This was done by investigating expression of selected inflammatory markers and integrity of epithelial monolayers in vitro. Rat oral keratinocytes were stimulated with heat-killed Fusobacterium nucleatum and Porphyromonas gingivalis over 7-days then bacteria were washed away and epithelial cells re-cultured for 3-days. Expression of IL-1β, IL-6, and IL-8 was measured by ELISA while transcription of tissue inhibitor of metalloproteinase-1 (TIMP-1) and matrix metalloproteinase -8 (MMP-8) was measured by polymerase chain reaction before and after removal of bacteria. Integrity of epithelial sheet was investigated by using transepithelial electrical resistance. Data showed general downregulation of IL-1b, IL-6, and IL-8 associated with restoring transcription of TIMP-1 and MMP-8 to normal level following removal of bacteria from epithelial cultures. However, expression of IL-8 and MMP-8 remained significantly higher than unstimulated epithelial cells despite withdrawal of F. nucleatum and P. gingivalis respectively from oral keratinocytes cultures. In addition, integrity of epithelial barrier function remained compromised even after removal of P. gingivalis. Results suggest that even after three days following removal of periodontal pathogens, oral keratinocytes sustained persistent upregulation of certain inflammatory markers that could compromise integrity of epithelial barrier function.
DOI: 10.6084/m9.figshare.14304796
title: The Ostensive Role in the Representation of Qualitative Statistics Variables

description: Abstract The essence of statistics is the possibility of extracting relevant information from data collected on aspects of reality. For this, the data are transformed into tables, graphs, and abstract measures. The student's understanding of these transformations is crucial for learning. In this article, we make theoretical reflections on the actions of students and the role of concrete material manipulated as ostensible in the management and display of qualitative statistics that undergo transformations in different semiotic records. For that, it uses the Theory of Semiotic Representation Records and the Anthropological Theory of Didactics, the latter limited to its perspective of ostensive and non-ostensive objects. The weightings indicate that the use of ostensive is motivating in the context of teaching and learning. Thus, it is expected that the reflections made here will contribute to a better understanding and teaching of statistical concepts, as well as to conducting new research.
DOI: 10.6084/m9.figshare.14304795
title: Enamel Subsurface Caries-Like Lesions Induced in Human Teeth By Different Solutions: A TMR Analysis

description: Abstract This study assessed the effectiveness of models for developing subsurface caries lesions in vitro and verified mineral changes by transverse microradiography (TMR). Enamel blocks from permanent (n=5) and deciduous teeth (n=5) were submitted to lesion induction by immersion in demineralizing solutions during 96 h, followed by pH cycles of demineralization (de) and remineralization (re) for 10 days. Two de-/re solutions were tested. Demineralizing solution “A” was composed by 2.2 mM CaCl2, 2.2 mM KH2PO4, 0.05 M acetic acid, with pH 4.4 adjusted by 1 M KOH. Demineralizing solution “B” was composed by 2.2 mM CaCl2, 2.2 mM NaH2PO4, 0.05 M acetic acid and 0.25 ppmF, with pH 4.5 adjusted by 1M KOH. Solution “A” produced cavitated lesions in permanent teeth, whereas solution “B” led to subsurface lesions in deciduous teeth. Solution “B” was then tested in enamel blocks from permanent teeth (n=5) and subsurface lesions were obtained, so that solution “B” was employed for both substrates, and the blocks were treated with slurries of a fluoride dentifrice (1450 ppm F, as NaF, n=5) or a fluoride-free dentifrice (n=5). Solution “B” produced subsurface lesions in permanent and primary teeth of an average (±SD) depth of 88.4µm (±14.3) and 89.3µm (±15.8), respectively. TMR analysis demonstrated that lesions treated with fluoride-free dentifrice had significantly greater mineral loss. This study concluded that solution “B” developed subsurface lesions after pH cycling, and that mineral changes were successfully assessed by TMR.
DOI: 10.6084/m9.figshare.14304793
title: Prevalence, Severity and Factors Associated with Dental Caries Among School Adolescents in Uganda: A Cross-Sectional Study

description: Abstract Dental caries is one of the most prevalent diseases in developing countries. However, there is limited data on the prevalence and factors associated with dental caries in Ugandan adolescents. The purpose of the present study was to describe the prevalence, severity of dental caries and to determine the factors associated with the disease among school adolescents in Uganda. A cross sectional study was conducted at two secondary schools from Kampala (n=197) and Mukono (n=209) districts, Uganda. At both schools, random sampling was used to select the participating classes and the 406 adolescents (11-19 years) eligible to participate in the research. Dental caries was examined using the Decayed, Missing and Filled Teeth (DMFT) index, and a questionnaire was used to collect other relevant data in form of an oral interview. The data were analyzed using STATA version 12. The data was declared as survey data and all analyses were done with svy command. The prevalence of caries was determined as a percentage of individuals with DMFT score ≥1. Modified Poisson regression models were utilized to assess the association between prevalence, severity of dental caries and independent variables. The overall prevalence of dental caries was 66.0% and mean DMFT score of 2.18±2.67. Dental caries prevalence and severity were significantly (p&lt;0.05) associated with tooth cleaning device, age and history of previous dental visit. There was a high prevalence and severity of dental caries among adolescents, which emphasizes the urgent need to develop and design appropriate interventions to reduce the disease burden.
DOI: 10.6084/m9.figshare.14304791
title: Comparative Effect of Calcium Mesoporous Silica Versus Calcium and/or Fluoride Products Against Dental Erosion

description: Abstract The aim of this study was to compare the effects of a single application of a new calcium mesoporous silica nanoparticle (Ca2+-MSN) versus other calcium and/or fluoride products against dental erosion. Enamel blocks were half-covered and assigned to six groups (n = 10): Ca2+-MSNs; casein phosphopeptide-amorphous calcium phosphate mousse (CPP-ACP); CPP-ACP/F− (900 ppm F−); titanium tetrafluoride (TiF4 1%); sodium fluoride (NaF 1.36%); and Milli-Q® water (negative control). A single application for each product was completed on the exposed areas of the blocks and were submitted to an erosive challenge. Differences in volumetric roughness (Sa), and tooth structure loss (TSL) by use of three-dimensional noncontact optical profilometry were evaluate. Scanning electron microscopy (SEM) was performed. Analysis of variance and Tukey’s test for Sa and the Kruskal-Wallis and Mann-Whitney U tests (p&lt; 0.05) for TSL, respectively. Results: When evaluating Sa, all products presented differences in roughness when compared with the control group (p&lt; 0.05) but not with each other (p &gt; 0.05). However, when analyzing the TSL, it was observed that Ca2+-MSNs, TiF4, and NaF were more effective in preventing dental erosion versus CPP-ACP, CPP-ACP/F−, and Milli-Q® water (p&lt; 0.05). In the SEM images, the negative control presented the worst loss of dental structure, with more porous enamel. Ca2+-MSNs were as effective as TiF4 and NaF to reduce the tooth structure loss.
DOI: 10.6084/m9.figshare.14304790
title: Association Between -1607 1G/2G Polymorphism of MMP1 and Temporomandibular Joint Anterior Disc Displacement with Reduction

description: Abstract Anterior disc displacement with reduction (DDWR) is considered one of the most common disorders within the temporomandibular joint (TMJ), with a prevalence of 41% in adults. Matrix metalloproteinases play an important role in the degradation of the TMJ and the matrix metalloproteinase 1 (MMP1) 1607 1G/2G polymorphism increases the local expression of MMP1 thus leading to accelerated degradation of the extracellular matrix. The objective of this study was to evaluate the association between the 1607 1G/2G polymorphism of MMP1 gene and DDWR in a group of Mexican individuals from western Mexico. A total of 67 unrelated individuals, between the ages of 18 and 36 years, of both genders, were included in this study. Study participants with DDWR were required to meet the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), while a second control group of 90 individuals without DDWR were also included. Both groups were required to have paternal and maternal ancestry (grandparents) of the same geographic and ethnic region. Genotypes were determined using the nested PCR technique. The 1G/2G polymorphism was found in 68.7%, followed by 2G/2G in 25.4% and 1G/1G in 6.0% of the cases group. While the prevalence in the control group was 55.5% for the 1G/2G polymorphism, 26.6% for 1G/1G and 17.7% for 2G/2G. An association was found between the 2G allele of the 1607 1G/2G polymorphism of MMP1 gene and the presence of DDWR in the patients of western Mexico.
DOI: 10.6084/m9.figshare.14304788
title: Dentinal Tubule Penetration of a Calcium Silicate-Based Root Canal Sealer Using a Specific Calcium Fluorophore

description: Abstract This study aimed to evaluate penetrability on dentinal tubule of a new bioceramic sealer through confocal laser scanning microscopy (CLSM). A specific fluorophore (Fluo-3) was mixed with the sealer. Forty distobuccal roots from maxillary molars were selected, and root canal preparation was carried out with Wave One Gold # 35.06 instruments. Roots were randomly assigned to 4 groups according to the filling procedures: Bioceramic/Lentulo (Sealer Plus BC); Bioceramic/EasyClean group, three activation of the sealer (3x20 s) with Easy Clean instrument; Bioceramic/Irrisonic: ultrasonic activation for 30 s; and AHplus/Lentulo: epoxy resin based sealer (AH Plus) was utilized with the same protocol as the BC/LE group. After 72 h, specimens were transversally sectioned at 2 and 7 mm from root apex and then analyzed through CLSM. Sealer penetration area on dentinal tubule was measured by Adobe Photoshop CC2018. Kruskal Wallis and Wilcoxon T tests were carried out. Penetrability results were similar for both sealers regardless of which technique was performed to activate them inside the root canal (p&gt;0.05). It is reasonable to conclude that penetration of bioceramic and epoxy resin based sealers occurred unimpressively. The type of instrument used to activate bioceramic sealer did not affect penetrability. Fluo 3 should be recommended as the fluorophore to evaluate dentinal tubule penetration of bioceramic sealers.
DOI: 10.6084/m9.figshare.14304786
title: Clinical Study of Sodium Hypochlorite, Polymyxin B And Limewater Effect on MMP-3,-8,-9 In Apical Periodontitis

description: Abstract This study aimed to evaluate sodium hypochlorite (NaOCl), limewater (LW), and Polymyxin B (PMB) as irrigants over MMP-3, MMP-8 and MMP-9. Thirty-three patients with apical periodontitis of single-rooted teeth were treated according to three-experimental groups (n=11): group-1: 2.5% NaOCl was used as irrigant; group-2: 2.5% NaOCl for the first two files and LW: [0.14% Ca(OH)2] for the last two files; group-3: 2.5% NaOCl for the first two files and PMB for the last two files. The association of Ca(OH)2 and CHX was used as an intracanal medication in all groups. Four root canal samplings (S) were collected: S1) immediately after access cavity; S2) after biomechanical preparation; S3) after EDTA application; and S4) after removal of the intracanal medication. After quantification of MMP-3, MMP-8, and MMP-9, the data were analyzed by Friedman and Kruskal-Wallis tests and completed by Dunn test (5%). Regardless the used irrigant, there was no difference in reducing MMP-3 or MMP-8 (P=0,5273, P=0,7048 respectively). However, in reducing MMP-9 (P=0,0246) the NaOCl group was the most effective followed by NaOCl+LW group and NaOCl+PMB group respectively. The intracanal medication [Ca(OH)2 + CHX] with the NaOCl and NaOCl+LW was effective in reducing MMP-8 (P&lt;0,0001, P=0,0025) and MMP-9 (P=0,0007, P=0,0047) respectively, but not for the group of NaOCl+PMB which was not effective in reducing MMP-8 or MMP-9 (P=0,1718, P=0,1953) respectively. NaOCl and NaOCl+LW were effective in reducing MMP-9 levels, and this effectivity could be improved by the use of the intracanal medication [Ca(OH)2 + CHX] in reducing MMP-8 and MMP-9 levels.
DOI: 10.6084/m9.figshare.14304785
title: Colombian Community of Mathematics Education: a documentary characterization

description: Abstract We characterize the Colombian research and innovation community in Mathematics Education from its open access documentary production. We analyzed the content of 3475 documents published by this community between 1983 and 2017, with a semantic approach, from a taxonomy of key terms specific to Mathematics Education. We analyzed the diachronic behavior of the documentation and established the thematic specialty, the evolution of the content over time through the sets of variables such as educational level, pedagogical notions, and mathematics topics, and the association between these sets. The results confirm that Mathematics Education in Colombia is a study front. The focal points of interest for the community are the undergraduate and secondary educational levels, the pedagogical notions of learning, classroom and teaching, and the topics of geometry, algebra, and numbers. This study leaves an open discussion regarding the role of research and innovation in the consolidation of Mathematics Education as a discipline.
DOI: 10.6084/m9.figshare.14304784
title: Internal and Marginal Fit and Fracture Strength of Narrow Diameter Dental Implant-Abutment Assembly

description: Abstract The aim of this study was to assess the internal and vertical marginal fit of metallic copings to abutments and the fracture strength of different narrow diameter dental implant/abutments, either submitted to thermomechanical cycling or not. Sixty-four implant/abutments (n=16) were divided into 4 groups according to diameter and abutment type: G3.5-UAC (morse taper implant Ø3.5mm + universal abutment with beveled chamfer finish); G2.9-UAS (morse taper implant Ø2.9mm + universal abutment with shoulder finish); G2.8-AA (morse taper friction implant Ø2.8mm + anatomical abutment) and G2.5-HP (one-piece implant Ø2.5mm with indexed hexagonal platform). Each group was divided into two subgroups (n=8): submitted and not submitted to thermomechanical cycling (TMC). To assess internal and vertical marginal fit of metallic copings, the assemblies were scanned using microtomography (micro-CT) (n=5). The samples were subjected to the compressive strength test on a universal test machine. Group G3.5-UAC showed the highest marginal misfit regardless of TMC (p&lt;0.05). All other groups were similar after TMC. Group G2.8-AA showed the lowest internal misfit both with and without TMC (p&lt;0.05). Group G2.8-AA showed the highest fracture strength, similar only to G2.5-HP without TMC and G3.5-UAC with TMC. The type of abutment affects the internal and marginal fit of metallic copings and the anatomical abutment led to the best internal and marginal coping fit. The narrow diameter dental implant/abutments differ in terms of fracture strength, the strongest assembly was that composed by implant of type V grade titanium without internal threads (friction implant).