Biocompatibility of sealers used in apical surgery: a histological study in rat subcutaneous tissue

The aim of this study was to evaluate the biocompatibility of sealers used in apical surgery in rat subcutaneous tissue. Sterile polyethylene tubes were filled with the following sealers: Sealapex, Sealapex with addition of zinc oxide, Sealer 26, Sealer 26 with thicker consistency (greater powder-to-resin ratio) and White MTA. The tubes were implanted in the dorsum of male rats and after 7, 21 and 42 days, the animals were killed, obtaining 5 specimens for each sealer in each evaluation period. The lateral surface of the tube was used as negative control. The inflammatory reaction to contact with the sealers was classified as absent, mild, moderate and severe. At 7 days, all sealers caused similar inflammatory reactions in the connective tissue of the animals, with most specimens presenting a moderate to intense chronic inflammatory reaction, with presence of multinucleated giant cells. At 21 days, Sealer 26 and Sealer 26 with thicker consistency presented more intense inflammatory reaction (p=0.004), whereas after 42 days, the inflammatory reaction ranged from absent to mild with statistically similar results for both materials (p=0.08). Except for MTA, all sealers presented foreign-body granulomatous reaction at 42 days. All sealers but Sealapex presented a statistically significant decrease of the inflammatory reaction over time. In conclusion, all sealers caused moderate to severe inflammation in the earlier evaluation period. However, Sealer 26 and Sealer 26 with thicker consistency caused more intense inflammatory reactions after 21 days of contact with the tissues and no granulomatous reaction was observed for MTA at the final period of analysis.     

Dominant form of arthrogryposis multiplex congenita with limited mouth opening: a clinical and imaging study

AIMS: Arthrogryposis multiplex congenita (AMC) is characterized by congenital contractures and joint deformities, but there are only a few reports of temporomandibular joint (TMJ) involvement. The objective of this investigation was to study the cause of limited mouth movement in this disease. MATERIALS AND METHODS: Four individuals from a family affected by AMC over 5 generations were examined clinically and by magnetic resonance imaging (MRI) and 3-dimensional computerized tomography (3D-CT). RESULTS: The CT scans of the 4 individuals showed hyperplasia of the coronoid process protruding into the infratemporal fossa in 2 of them and cranially to the zygomatic arch in the other 2; the hyperplasia was associated with mechanical limitation of the mouth opening. The MRI showed a disc displacement with reduction in 1 patient and a disc displacement without reduction in another; disc displacement could not be evaluated because of the limited mouth opening in the other 2. The condyle-disc complex of these last 2 individuals could only rotate. The MRI on T2-weighted images showed disc hyposignal in all cases but no alterations in the masticatory muscle tissue. The pedigree of the family suggests an autosomal dominant form of inheritance. CONCLUSIONS: The restriction of mouth opening in the 4 individuals affected by AMC was likely due to osseous dysplasia.     

Natural history of intraventricular meningiomas: systematic review

Review the data published on the subject to create a more comprehensive natural history of intraventricular meningiomas (IVMs). A Medline search up to March 2018 using “intraventricular meningioma” returned 98 papers. As a first selection step, we adopted the following inclusion criteria: series and case reports about IVMs, as well as papers written in other languages, but abstracts written in English were evaluated. Six hundred eighty-one tumors were evaluated from 98 papers. The majority of the tumors were located in the lateral ventricles (602–88.4%), fourth ventricle (59–8.7%), and third ventricle (20–2.9%). These tumors accounted for a mortality rate of 4.0% (25 deaths) and a recurrence rate of 5.3% (26 recurrences). The majority of the tumors were grade I (89.8%) and consisted of the following subtypes: fibrous, 39.7% (n = 171); transitional, 22.0% (n = 95); meningothelial, 18.6% (n = 80); angiomatosus, 3.2% (n = 14); psammomatous, 2.6% (n = 11); and others, 13.9% (n = 60). Forty-five patients (7.4%) presented with grade II (GII) tumors, and 17 patients (2.8%) presented with grade III (GIII) tumors. These tumors follow the histopathological distribution of meningiomas in general, with the exception of the higher prevalence of the fibrous subtype, possibly due to its embryonic origin. Recurrence and mortality were lower than in other localizations likely due to a complete surgical resection rate than in the convexity and skull base, which suggests that GTR is the gold standard for the management of IVMs.     

Platelet‐Rich Plasma,Low‐Level Laser Therapy,or Their Combination Promotes Periodontal Regeneration in Fenestration Defects: A Preliminary In Vivo Study

Background: This study histomorphometrically analyzes the influence of platelet‐rich plasma (PRP), low‐level laser therapy (LLLT), or their combination on the healing of periodontal fenestration defects (PFDs) in rats. Methods: PFDs were surgically created in the mandibles of 80 rats. The animals were randomly divided into four groups: 1) C (control) and 2) PRP, defects were filled with blood clot or PRP, respectively; 3) LLLT and 4) PRP/LLLT, defects received laser irradiation, were filled with blood clot or PRP, respectively, and then irradiated again. Animals were euthanized at either 10 or 30 days post‐surgery. Percentage of new bone (NB), density of newly formed bone (DNB), new cementum (NC), and extension of remaining defect (ERD) were histomorphometrically evaluated. Data were statistically analyzed (analysis of variance; Tukey test, P <0.05). Results: At 10 days, group PRP presented ERD significantly lower than group C. At 30 days, group PRP presented NB and DNB significantly greater than group C. Groups LLLT, PRP, and PRP/LLLT showed significant NC formation at 30 days, with collagen fibers inserted obliquely or perpendicularly to the root surface. NC formation was not observed in any group C specimen. Conclusions: LLLT, PRP, or their combination all promoted NC formation with a functional periodontal ligament. The combination PRP/LLLT did not show additional positive effects compared to the use of either therapy alone.     

Media and scientific communication about the COVID-19 pandemic and the repercussions on the population's mental health: A protocol for a systematic review and meta-analysis

Background:Good communication strategies are essential in times of crisis, such as the coronavirus pandemic. The dissemination of inaccurate information and the need for social isolation to control coronavirus disease 2019 (COVID-19) have shown a negative impact on the population, causing damage to mental health, with the appearance or worsening of symptoms of stress, fear, anxiety, and depression. Thus, the systematic review study is intended to gather evidence on the impact of information about COVID-19 on the mental health of the population.Methods:This systematic review protocol is conducted using the guidelines of the preferred reporting items for systematic reviews and meta-analyses protocols and the Cochrane Handbook for Systematic Reviews of Interventions. The review aims to include published studies that address the exposure of the general population to information about COVID-19, through observational and experimental studies, which consider the following outcomes: fear, stress, anxiety, and depression. Thus, a comprehensive research strategy will be conducted in the following databases: PubMed / Medline, Scopus, Web of Science, EMBASE, Science Direct, CINAHL, PsycINFO and Cochrane Central Register of Controlled Trials (CENTRAL). Two independent reviewers will perform all procedures, such as study selection, data collection, and methodological evaluation. Disagreements will be forwarded to a third reviewer. RevMan 5.3 software will be used for data analysis.Results:This systematic review will provide evidence of the influence of access to and consumption of media and scientific information about COVID-19 on the mental health of the population. It will consider information about the characterization of the study and the population studied, clinical and epidemiological information on mental health, and data on access to and consumption of media and scientific information.Discussion:The results should inform about the consequences of communication about the new coronavirus on the emergence or worsening of psychological and psychiatric symptoms, allowing to develop strategies to achieve effective communication of information to promote the mental health of the population.Systematic review registration number:PROSPERO CRD42020182918