Abordaje terapéutico del tumor odontogénico queratoquístico

El tumor odontogénico queratoquístico fue clasificado como tumor odontogénico benigno por la Organización Mundial de la Salud en el año 2005. Esta lesión se caracteriza por su comportamiento localmente agresivo, su alta tasa de recidiva y su potencial de malignización. Generalmente se presenta de forma única y unilocular en la mandíbula, pero también es frecuente su relación con el Síndrome de Gorlin. Dado que no existe un consenso acerca del tratamiento ideal para el tumor odontogénico queratoquístico, el presente Trabajo de Fin de Grado tiene como objetivo desarrollar unas directrices que ayuden a decidirlo.The odontogenic keratocystic tumor was classified by the World Health Organization as a benign neoplasm in 2005. The tumor has a characteristic locally aggressive behavior, a high recurrence rate, and also a propensity to malignancy. The injury is usually related to an unilocular appearance and is generally found in mandible, and the lesion could be diagnosed in patients with Gorlin syndrome. The aim of this study is to find a global approach in the treatment for the KCOT.Universidad de Sevilla. Grado en Odontologí

In vitro comparative study of fibroblastic behaviour on polymethacrylate (PMMA) and lithium disilicate polymer surfaces

Polymethyl methacrylate (PMMA) and lithium disilicate are widely used materials in the dental field. PMMA is mainly used for the manufacture of removable prostheses; however, with the incorporation of CAD-CAM technology, new applications have been introduced for this material, including as a provisional implant attachment. Lithium disilicate is considered the gold standard for definitive attachment material. On the other hand, PMMA has begun to be used in clinics as a provisional attachment until the placement of a definitive one occurs. Although there are clinical studies regarding its use, there are few studies on cell reorganization around this type of material. This is why we carried out an in vitro comparative study using discs of both materials in which human gingival fibroblasts (HGFs) were cultured. After processing them, we analyzed various cellular parameters (cell count, cytoskeleton length, core size and coverage area). We analyzed the surface of the discs together with their composition. The results obtained were mostly not statistically significant, which shows that the qualities of PMMA make it a suitable material as an implant attachment

Biocompatibility of Polymer and Ceramic CAD/CAM Materials with Human Gingival Fibroblasts (HGFs)

Four polymer and ceramic computer-aided design/computer-aided manufacturing (CAD/CAM) materials from different manufacturers (VITA CAD-Temp (polymethyl methacrylate, PMMA), Celtra Duo (zirconia-reinforced lithium silicate ceramic, ZLS), IPS e.max CAD (lithium disilicate (LS2)), and VITA YZ (yttrium-tetragonal zirconia polycrystal, Y-TZP)) were tested to evaluate the cytotoxic effects and collagen type I secretions on human gingival fibroblasts (HGFs). A total of 160 disc-shaped samples (Ø: 10 ± 2 mm; h: 2 mm) were milled from commercial blanks and blocks. Direct-contact cytotoxicity assays were evaluated at 24, 48, and 72 h, and collagen type I (COL1) secretions were analysed by cell-based ELISA at 24 and 72 h. Both experiments revealed statistically significant differences (p < 0.05). At 24 and 48 h of contact, cytotoxic potential was observed for all materials. Later, at 72 h, all groups reached biologically acceptable levels. LS2 showed the best results regarding cell viability and collagen secretion in all of the time evaluations, while Y-TZP and ZLS revealed intermediate results, and PMMA exhibited the lowest values in both experiments. At 72 h, all groups showed sharp decreases in COL1 secretion regarding the 24-h values. According to the results obtained and the limitations of the present in vitro study, it may be concluded that the ceramic materials revealed a better cell response than the polymers. Nevertheless, further studies are needed to consolidate these findings and thus extrapolate the results into clinical practic

A Comparison of Photoelastic and Finite Elements Analysis in Internal Connection and Bone Level Dental Implants

This study is a contribution to our understanding of the mechanical behaviour of dental implants through the use of the finite element and the photoelastic methods. Two internal connection and bone level dental implants with different design have been analysed (M-12 by Oxtein S.L., Zaragoza, Spain, and ASTRA, from Dentsply Sirona, Charlotte, NC, USA), evaluating the stress distribution produced by axial stresses and a comparison has been established between them, as well as between the two methods used, in order to validate the adopted hypotheses and correlate the numerical modelling performed with experimental tests. To load the implant in laboratory testing, a column was placed, such that the loading point was about 9.3 mm from the upper free surface of the resin plate. This column connects the implant with the weights used to define the test load. In turn, support for both plates was achieved by two 6 mm bolts 130 mm apart and located on a parallel line with the resin (flush with the maximum level of the implant), at a depth of 90 mm. The results obtained with both methods used were similar enough. The comparison of results is fundamentally visual, but ensures that, at least in the range of forces used, both methods are similar. Therefore, the photoelastic method can be used to confirm in a real way the virtual conditions of the finite element models, with the implications in the investigation of dental implants that this entails

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

A Review on CAD/CAM Yttria-Stabilized Tetragonal Zirconia Polycrystal (Y-TZP) and Polymethyl Methacrylate (PMMA) and Their Biological Behavior

Yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) and polymethyl methacrylate (PMMA) are used very often in dentistry. Y-TZP is the most widely used zirconia dental ceramic, and PMMA has classically been used in removable prosthesis manufacturing. Both types of materials are commercialized in CAD/CAM system blocks and represent alternatives for long-lasting temporary (PMMA) or definitive (Y-TZP) implantological abutments. The aim of the present work is to reveal that human gingival fibroblasts (HGFs) have a favorable response when they are in contact with Y-TZP or PMMA as a dental implant abutment or implant-supported fixed prosthesis, and also to review their principal characteristics. We conducted an electronic search in the PubMed database. From an initial search of more than 32,000 articles, the application of filters reduced this number to 5104. After reading the abstracts and titles, we reduced the eligible articles to 23. Ultimately, we have included eight articles in this review

<i>In vitro</i> Comparative Study of Fibroblastic Behaviour on Polymethacrylate (PMMA) and Lithium Disilicate Polymer Surfaces

Polymethyl methacrylate (PMMA) and lithium disilicate are widely used materials in the dental field. PMMA is mainly used for the manufacture of removable prostheses; however, with the incorporation of CAD-CAM technology, new applications have been introduced for this material, including as a provisional implant attachment. Lithium disilicate is considered the gold standard for definitive attachment material. On the other hand, PMMA has begun to be used in clinics as a provisional attachment until the placement of a definitive one occurs. Although there are clinical studies regarding its use, there are few studies on cell reorganization around this type of material. This is why we carried out an in vitro comparative study using discs of both materials in which human gingival fibroblasts (HGFs) were cultured. After processing them, we analyzed various cellular parameters (cell count, cytoskeleton length, core size and coverage area). We analyzed the surface of the discs together with their composition. The results obtained were mostly not statistically significant, which shows that the qualities of PMMA make it a suitable material as an implant attachment

Effect of intravenous iron on functional outcomes in hip fracture: a randomised controlled trial

Objectives: to determine the safety and effect of intravenous iron sucrose on functional outcomes, delirium, nosocomial infections and transfusion requirements in older patients with hip fracture. Design: single-centre randomised, double-blind, placebo-controlled clinical trial. Setting and participants: orthogeriatric share care service at an academic tertiary care hospital. A total of 253 patients were recruited: 126 patients were assigned to intravenous iron and 127 to placebo. Methods: on days 1, 3 and 5 after admission, the iron group received 200 mg Venofer® (iron sucrose) in 100 ml saline and the placebo group 100 ml saline. The primary outcome was absolute functional gain, considered as Barthel index (BI) at discharge minus BI on admission. Secondary outcomes included incidence of postoperative delirium according to the confusion assessment method, proportion of patients recovering prior functional status at 3 months, postoperative transfusion requirements, haemoglobin at 3 months, incidence of nosocomial infections and safety. Results: the median participant age was 87 (interquartile range, 82.5-91.5) years. Most patients were female (72.7%), and the median previous BI was 81(59-95). No significant effect of intravenous iron was observed for the primary outcome: the median AFG score was 17.1 points (4.8-23.3) in the intravenous iron group and 16 points (6-26) in the placebo group (P = 0.369). No significant treatment effects were observed for other functional outcomes or secondary end points. Conclusion: while we found no impact of intravenous iron sucrose on functional recovery, incidence of postoperative delirium, transfusion requirements, haemoglobin at 3 months, mortality and nosocomial infections rates in older patients with hip fracture, we did find that the intervention was safe.Universidad Europea de Madrid (UEM_2016_285)12.782 Q1 JCR 20211.750 Q1 SJR 2021No data IDR 2021UE