Carolina Maschietto Pucinelli

This study aimed to investigate the role of Toll‐like receptor 2 (TLR2) in the progression of periapical lesions by evaluating NLRP3 inflammasome and interleukin‐1 beta (IL‐1β) expression in wild‐type (WT) and TLR2 knockout (KO) mice. A total of 55 mice (28 WT, 27 TLR2‐KO) underwent pulpal exposure of mandibular first molars and were euthanised at 7, 21, or 42 days post‐exposure. Histological and immunohistochemical analyses were performed. TLR2‐KO mice showed significantly larger periapical lesions and higher IL‐1β expression than WT mice after 21 and 42 days, respectively. In contrast, NLRP3 expression was significantly greater in WT mice at both time points. A weak but significant positive correlation between NLRP3 and IL‐1β expression was observed only in WT mice. These findings suggest that TLR2 plays a protective role in limiting periapical bone resorption and modulating inflammatory cytokine expression, independent of NLRP3 inflammasome activity.

This study evaluated the tissue reaction and inflammatory response after implantation of endodontic sealers in the subcutaneous connective tissue of isogenic mice. 120 mice were divided into 4 groups: BioRoot RCS, AH-Plus jet, ZOE and Sham group (negative control), which were evaluated in the experimental periods of 7, 21 and 63 days (n= 10). A macroscopic analysis was performed through digitized photograph to measure the thickness of the reaction tissue. Microscopic analysis were performed to count the number of blood vessels present in the reaction tissue and to evaluate collagen fiber networks. Data were analyzed using the non-parametric Kruskal-Wallis test and Dunn’s post-test (α=5%). The reaction tissue showed greater thickness and amount of vessels and blood cells in the initial period of 7 days and was reduced over time, except the group AH Plus Jet which presented similar values of blood cells and vessels in all experimental periods. The BioRoot RCS at 7 days, presented the values of thickness and blood cells in the reaction tissue significantly higher (p˂ 0.001). Regarding collagen fiber formation, there was a greater amount of collagen fibers in the Sham group (7, 21 and 63 days), BioRoot at 63 days and AH Plus Jet at 21 and 63 days. In conclusion, endodontic cements presented greater thickness and amount of blood cells in the initial period, being reduced with time. On the other, collagen fiber formation were more pronounced at final periods.

Background This study evaluated the altered expression levels of genes and cytokines associated with M1 and M2 macrophages during the development of periapical lesion (PL).

To evaluate the inflammatory tissue response to BioRoot™ RCS (BR) and AH Plus Jet (AHPJ) sealers implanted in mice subcutaneous tissue. It was hypothesized that the inflammatory tissue response to BR would be milder than to AHPJ. An in vivo study was carried out using isogenic mice. The sealers were implanted during standardized surgical procedures. The inflammatory response was evaluated by microscopic analysis and von Kossa reaction in the reactionary tissue around the specimens after 7, 21, and 63 days. For comparisons, a zinc oxide and eugenol sealer (ZOE) was used as a positive control, in addition to a negative control without a sealer (n = 10 per group/period). All statistical analyses considered a significance level of 5%. All endodontic sealers triggered an inflammatory tissue response after 7 days. BR had a higher inflammatory cell count and a thicker fibrous capsule when compared with AHPJ, but both were less inflammatory than ZOE (p < .001). After 21 days, BR continued to trigger an intense inflammatory tissue response, higher in both microscopic parameters compared to AHPJ, and a thicker fibrous capsule than ZOE (p < .001). After 63 days, the inflammatory tissue response decreased in BR, matching the fibrous capsule thickness with AHPJ and ZOE. BR promoted intense calcium precipitation in all study periods. After 63 days, AHPJ and BR sealers were more biocompatible to subcutaneous mice tissue, but AHPJ present better early inflammatory response, as well as BR showed potential bioactivity.Research Highlights: The inflammatory tissue response triggered by a bioceramic endodontic sealer (BR) was not milder than that triggered by an epoxy‐resin based endodontic sealer (AHPJ) during the first 3 weeks, considering the microscopic analysis of the reactionary tissue.

Aim: To evaluate the psychological impact of COVID-19 on undergraduate and graduate students of the Dental School of Ribeirão Preto, University of São Paulo. Methods: Three questionnaires were used: sociodemographic, WHO Abbreviated Quality of Life Inventory, and General Anxiety Disorder-7. Data were analyzed using Graph Pad Prism 7a (α = 5%). Mann-Whitney or Kruskal-Wallis and Dunn post-tests were used for statistical comparisons. The Spearman test was used as the correlation test. Results: 257 students responded to the online form that assessed their quality of life and anxiety level. On a scale from 1 to 100, with 100 being the best quality of life, the average obtained was 64.71 (± 13.36). In addition, 87.6% of the students rated their quality of life as good or very good. 74.7% reported good or very good health. The anxiety analysis resulted in an average of 10.04 (± 4.5), indicating moderate anxiety levels. There was an inversely proportional correlation between age and degree of anxiety (p = 0.008, r = -0.1628) and self-perceived learning and student commitment (r = 0.69). Conclusion: Despite the good quality of life and the students’ good self-perception of health, they showed a moderate degree of anxiety during the social distancing caused by COVID-19, also demonstrating a decrease in interest and commitment during distance education.

Aim: The aim of this study was to evaluate the IFI16 and IFN‐α/β receptors expression during the genesis and development of experimental apical periodontitis (AP) in mice teeth.Methodology: Apical periodontitis was induced in the lower first molars of 40 C57BL/6 mice. They were divided according to the experimental periods 2, 7, 14, 21 and 42 days (n = 8 per group). Five animals were used as a control group (without AP). Specimens were submitted to histological processing for description of the inflammatory process, immunostaining for the presence/absence and localization of IFI16 and IFN‐α/β receptors (qualitative and semi‐quantitative analysis) and tartrate‐resistant acid phosphatase (TRAP) histoenzimology.Results: The results showed a gradual development of AP over the experimental times. The expression of IFI16 was noticeably more exacerbated in the experimental early period (day 2) whilst the lowest expression was observed in the control group (p = .02). For IFN‐α/β receptors, a higher intensity staining was observed 42 days after AP induction, that was statistically different from the control group (p = .02). In addition, the number of TRAP‐positive cells was higher on the later periods (days 21 and 42; p < .001).Conclusion: IFI16 protein expression was highest during the early periods after AP induction in mice teeth, whilst IFN‐α/β receptor expression was highest after AP became established.

The aim of this study was to evaluate the subcutaneous connective tissue response of isogenic mice exposed to tricalcium silicate (Biodentine) and aggregated mineral trioxide (ProRoot MTA). A total of 120 mice were divided into 4 groups in 3 different experimental periods (7, 21 and 63 days): Biodentine; Pro-Root MTA; zinc oxide-eugenol and; Negative control - Sham. After the experimental periods microscopic descriptive, semi-quantitative and quantitative analysis of the inflammatory process were analyzed on H&E sections and evaluation of the gene expression of Il10, Infg, Il6, Il1r1 and Tnf (qRT-PCR) were performed. The data obtained were analyzed using the chi-square test and two-way analysis of variance (ANOVA) followed by the Bonferroni post-test (5% significance level). Results: In the microscopic analysis, a slight inflammatory infiltrate was observed, with a predominance of sparse macrophages and polymorphonuclear cells, slight tissue fibrosis, regular fibrous capsule and with dystrophic calcifications, in all groups that received the materials (Biodentine and Pro-Root MTA). In parallel, all materials modulated the gene expression of the different cytokines and receptors evaluated. Conclusion: Pro-Root MTA and Biodentine showed a tissue compatibility, mediated inflammation, with increased fibrous tissue and production of pro- and anti-inflammatory cytokines.

The COVID-19 pandemic led to changes in academic teaching and dental education, but the impact on dental professors' mental health and quality of life remains poorly understood. Thus, the objective of this study was to evaluate the impacts of social distancing and online teaching related to COVID-19 on the quality of life and anxiety of Brazilian dental professors. This was a cross-sectional study conducted from August 2020 to October 2020. Three instruments were used in an online version: a questionnaire about personal data, academic information and online teaching activities, the Generalized Anxiety Disorders 7 (GAD7) scale, and the Abbreviated World Health Organization Quality of Life (WHOQOL-bref) scale. All instruments were sent by e-mail, social media, and messaging apps to private and public universities and professors. Of the 318 responses, 187 (58.8%) were from female professors. Moreover, lack of good internet access and adequate place for online teaching, difficulties in producing teaching materials, and housework roles had a significant impact on the quality of life and anxiety scores (all p-values < 0.05). Also, Brazilian dental professors who declared that they would make greater efforts if the activities were face-to-face had significantly worse quality of life and anxiety scores, and female professors had significantly higher anxiety scores (all p-values < 0.05). These results provide evidence of a negative effect of social distancing and online teaching activities related to COVID-19 outbreak on the health-related quality of life and mental health of Brazilian dental professors.

Introduction: The 2q37.3 deletion syndrome is a disorder caused by the microdeletion of a subband on chromosome 2, whose epidemiology is approximately 150 cases worldwide, and the prevalence of 1: 10000. Its characteristics are developmental delay, facial dysmorphia, musculoskeletal abnormalities, and increased risk of congenital diseases. The purpose is to present, for the first time in the literature, the oral and dental clinical findings associated with the syndrome. Case report: The main physical characteristics of the syndrome were identified during the physical examination: thin upper lip, prominent columella, and epicanthic folds. In the intraoral examination, dental characteristics were reported, which may be associated with the syndrome: accumulation of dental calculus, hypomineralization and hypoplasia, crossbite, open bite, agenesis, taurodontism, and dentigerous cyst. The dental treatment consisted of the application of behavior management techniques, hygiene and diet instruction, prophylaxis, supragingival scraping, topical fluoride application, and extraction of the lower second molar. This is the first report of oral characteristics of the 2q37.3 deletion syndrome, giving importance to the characteristics observed in this patient. Such findings will be useful in the characterization of the syndrome, which is extremely rare, and may contribute to the clinical diagnosis of these patients, in addition to subsidizing the dental treatment of other individuals. Conclusion: We present oral clinical findings such as hypomineralization and hypoplasia, crossed and an open bite, agenesis, taurodontism, and dentigerous cyst present in the patient with the syndrome and we suggest that the involved gene or its deletion may be responsible for such findings.

Background/Aim: The high rate of root resorption resulting from tooth replantation represents a serious clinical problem. In order to prevent ankylosis and replacement resorption, the contemporary literature highlights the importance of using a flexible stabilization for traumatized teeth. For this purpose, orthodontic devices may be promising for obtaining a better prognosis and periodontal repair. The aim of this study was to evaluate the effect of an active splinting protocol with controlled force in dog's teeth following replantation.Material and Methods: Sixty premolar roots from three dogs were used. They were submitted to endodontic treatment, hemisected, atraumatically extracted and subsequently replanted. They were divided into four groups: Passive Stabilization (n = 20)‐after 20 min in a dry medium; Active Stabilization (n = 20)‐after 20 min in a dry medium; Negative control (n = 10)‐immediate replantation and passive Stabilization; and Positive control (n = 10)‐90 min of extra‐alveolar time and passive Stabilization. The samples were collected and submitted to histologic processing. They were then evaluated for the count of inflammatory cells, expression of neurotrophin 4, osteoclasts, apoptotic cells and collagen fibres. The results were submitted to ANOVA or Kruskal‐Wallis statistical tests followed by Tukey or Dunn post‐tests (α = 5%).Results: Passive Stabilization with orthodontic brackets without traction used after replantation had the highest number of inflammatory cells (p = .0122), osteoclasts (p = .0013) and percentage of collagen fibres in the periodontal ligament (p < .0001) when compared to Active Stabilization with orthodontic brackets applying amild tensile force. Neurotrophin 4 had no statistically significant difference (p = .05), regardless of the treatment. The apoptotic cells count revealed statistical differences (p < .0001) between Active Stabilization (189.70 ± 47.99) and Positive Control (198.90 ± 88.92) when compared to Passive Stabilization (21.19 ± 32.94).Conclusion: The active splinting protocol using orthodontic appliances generating a light and controlled force favoured periodontal ligament repair of replanted teeth.