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Dental pulp is a highly specialized mesenchymal tissue that has a limited regeneration capacity due to anatomical arrangement and postmitotic nature of odontoblastic cells. Entire pulp amputation followed by pulp space disinfection and filling with an artificial material cause loss of a significant amount of dentin leaving as life-lasting sequelae a non-vital and weakened tooth. However, regenerative endodontics is an emerging field of modern tissue engineering that has demonstrated promising results using stem cells associated with scaffolds and responsive molecules. Thereby, this article reviews the most recent endeavors to regenerate pulp tissue based on tissue engineering principles and provides insightful information to readers about the different aspects involved in tissue engineering. Here, we speculate that the search for the ideal combination of cells, scaffolds, and morphogenic factors for dental pulp tissue engineering may be extended over future years and result in significant advances in other areas of dental and craniofacial research. The findings collected in this literature review show that we are now at a stage in which engineering a complex tissue, such as the dental pulp, is no longer an unachievable goal and the next decade will certainly be an exciting time for dental and craniofacial research.

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This study evaluated the effects of immediate and delayed polishing on the surface roughness, microhardness and microleakage of a microfilled (Filtek A110) and a hybrid (Filtek Z250) resin composite. Standardized preparations were made on the buccal surfaces of 256 bovine teeth; half were restored with each composite (128 teeth per composite). Immediately after curing, gross finishing was carried out with #280 sandpaper. The specimens restored with each composite were divided into two subgroups. The first group (IM) was polished immediately after gross finishing, using three different systems (n=16): Sequence A, Sof-Lex; Sequence B, Flexicups and Sequence C, Flexicups + Jiffy Polishing Brush + Flexibuffs. The specimens were then stored for three weeks in saline 37 degrees C. The second group (DE) was stored for two weeks, then polished with the same systems and stored for one additional week. The controls (n=16) were analyzed without polishing. Five readings per specimen were taken for surface roughness and hardness. After immersion in basic fuchsin, microleakage was evaluated (40x) using standardized scores. The data were analyzed at a significance level of 0.05, with analysis of variance and an SNK test (surface roughness and microhardness) or with Kruskal-Wallis (microleakage). In both composites, only for the sequential technique was there an influence of delay in polishing on roughness (Ra). Flexicups exhibited the highest Ra of the three systems. The IM and Filtek Z-250 groups showed higher hardness than the DE and Filtek A-110 groups, respectively. Dentin margins showed more leakage than enamel margins; the sequential technique produced more leakage than the other techniques in dentin (p<0.05) and delay of polishing was not significant in the majority of situations. In conclusion, several conditions--composite, time and polishing technique--had a significant influence on surface roughness, hardness and microleakage. Generally, immediate polishing produced no detrimental effect compared to delayed polishing.

A nationwide survey of dentists was carried out in Brazil, a new pandemic epicenter, to analyze how dental care coverage has been affected in public versus private networks, changes in routine and burdens, and how local prevalence of COVID-19 affects dental professionals. Dentists were recruited via email and Instagram®. Responses to a pre-tested questionnaire were collected May 15–24, 2020. COVID-19 case/death counts in the state where respondents work was used to test associations between contextual status and decreases in weekly appointments, fear of contracting COVID-19 at work, and current work status (α = 0.05). Over 10 days, 3,122 responses were received (response rate ~2.1%) from all Brazilian states. Work status was affected for 94%, with less developed regions being more impacted. The pandemic impact on clinical routine was high/very high for 84%, leading to varied changes to clinic infrastructure, personal protective equipment use, and patient screening, as well as increased costs. COVID-19 patients had been seen by 5.3% of respondents; 90% reported fearing contracting COVID-19 at work. Multilevel models showed that greater case and death rates (counted as 1000 cases and 100 deaths per million inhabitants) in one’s state increased the odds of being fearful of contracting the disease (18% and 25%). For each additional 1000 cases/100 deaths, the odds of currently not working or treating only emergencies increased by 36% and 58%. The reduction in patients seen weekly was significantly greater in public (38.7±18.6) than in private clinics (22.5±17.8). This study provides early evidence of three major impacts of the pandemic on dentistry: increasing inequalities due to coverage differences between public and private networks; the adoption of new clinical routines, which are associated with an economic burden for dentists; and associations of regional COVID-19 incidence/mortality with fear of contracting the disease at work.

There are no prospective studies investigating the effects of sugar-related feeding practices on changes in dental caries from early childhood to young adulthood. The aim of this study was to assess whether sugar-related feeding practices affect dental caries between the ages of 6 and 18 y. This birth cohort study was initiated in 1993 in Pelotas, Brazil. There were 3 dental clinical assessments; at ages 6 y (n = 359), 12 y (n = 339), and 18 y (n = 307). Sugar-related feeding practices were assessed at ages 4, 15, and 18 y. Covariates included sex and life course variables, such as family income, breast-feeding, mother's education, regularity of dental visit, and child's toothbrushing habits. Group-based trajectory analysis was performed to characterize trajectories of time-varying independent variables that had at least 3 time points. We fitted a generalized linear mixed model assuming negative binomial distribution with log link function on 3-time repeated dental caries assessments. One in 5 participants was classified as "high" sugar consumers, and nearly 40% were "upward consumers." "Low consumers" accounted for >40% of the sample. High and upward sugar consumers had higher dental caries prevalence and mean DMFT in all cohort waves when compared with low sugar consumers. Caries occurred at a relatively constant rate over the period of study, but in all sugar consumption groups, the increment of dental caries was slightly higher between ages 6 and 12 y than between 12 and 18 y. Adjusted analysis showed that dental caries increment ratio between ages 6 and 18 y was 20% and 66% higher in upward and high sugar consumer groups as compared with low consumers. The higher the sugar consumption along the life course, the higher the dental caries increment. Even the low level of sugar consumption was related to dental caries, despite the use of fluoride.

Mental and oral health are among the main disabilities worldwide. This article helps to understand more about the relationship between both conditions, highlighting the importance for both clinicians and policy makers of considering individual's psychological status in management of oral health.

Portland cement has been analyzed and compared to mineral trioxide aggregate (MTA) because of their chemical similarity. The possibility of using this material as a less expensive alternative to MTA in dental practice should be considered. In view of this, the present study compared the components of a Portland cement (Votoran®) to two commercial brands of MTA (Pro-Root™ and MTA-Angelus®). Twelve specimens of each material were fabricated and examined by scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) to obtain their percentage of chemical elements. The means of the chemical elements found in each material was compared by descriptive statistics. Bismuth was present only in MTA cements to provide radiopacity. In conclusion, the tested cements have similar components, which supports, as far as composition is concerned, the possible clinical use of Portland as an option to MTA.