Adhesion and proliferation of human dental pulp stem cells on a laser micro textured implant surface: An in vitro study

The roughness of the implant surface and its chemistery and toporaphy were demonstrated to impact cells biological properties. A moderate roughness seems to allow better and faster adhesion and proliferation and to accelerate the biological processes. The different physical and chemical procedures used to obtain a certain microtopography modify the surface chemical composition and, in consequence of it, can affect the biological cell behavior. The ideal surface shuold be obtained through processes that do not modify the chemical composition maintaining a right roughness and microtopography. The aim of this investigation was to study the morphology, proliferation and pattern of distribution of human Dental Pulp Stem Cells (hDPSCs) after 5 days of growth on a laser micro-grooved implant surface (Laser-Lock, Bio Horizons IPH, Inc. Birmingham, AL 35244, USA) characterized by a micro geometric design obtained by computer-aided laser ablation without any chemical treatment. Data from SEM surface observation and XPS chemical analysis have highlighted the absence of contaminating chemical elements. The results from cell cultures indicated that the hDPSCs maintained a good morphology and well proliferated following the microgrooves direction

Cytotoxic Evaluation of Elastomeric Dental Impression Materials on a Permanent Mouse Cell Line and on a Primary Human Gingival Fibroblast Culture

The need for clinically relevant in vitro tests of dental materials is widely recognized. Nearly all dental impression materials are introduced into the mouth just after mixing and allowed to set in contact with the oral tissues. Under these conditions, the materials may be toxic to cells or may sensitize the tissues. The aim of the present study is to evaluate the potential cytotoxicity of new preparations of elastomeric dental impression materials: A) four vinylpolysiloxanes: Elite H-D Putty and Elite H-D Light Body (Zhermack, Badia Polesine, Rovigo, Italy); Express Putty and Express Light Body (3M ESPE AG Seefeld, Germany) and B) two polyethers: Impregum Penta and Permadyne Penta L (3M ESPE AG Seefeld, Germany). The cytotoxicity of these impression materials were examined using two different cell lines: Balb/c 3T3 (permanent cell line) and human gingival fibroblasts (primary cell line) and their effects were studied by indirect and direct tests. The direct tests are performed by placing one sample of the impression materials in the centre of the Petri dishes at the time of the seeding of cells. The cell growth was evaluated at the 12th and 24th hours by cell number. The indirect tests were performed by incubating a square of 1 cm diameter impression material in 5 mL of medium at 37 °C for 24 hours (“eluates”). Subconfluent cultures are incubated with “eluates” for 24 hours. The MTT-formazan production is the method used for measuring the cell viability. The results indicate that: a) polyether materials are cytotoxic under both experimental conditions; b) among vinylpolysiloxanes, only Express Light Body (3M ESPE AG Seefeld, Germany) induces clear inhibition of cellular viability of Balb/c 3T3 evaluated by direct and indirect tests and c) the primary cell line is less sensitive to the toxic effect than the permanent cell line

Psychological reactions to COVID-19 and epidemiological aspects of dental practitioners during lockdown in Italy

BACKGROUND: Due to droplet production and exposure to saliva and blood, dental practitioners are at high risk of COVID-19 contagion during their routine procedures. The aim of this study was to investigate the behavior of Italian dentists and to analyze their reactions in relation to Sars-CoV-2 pandemic professional restrictive measures.METHODS: An online structured survey composed of 40 questions has been sent to dental practitioners all over Italy to investigate their behavior and to analyze their reactions in relation to Sars-CoV-2 pandemic restrictive measures introduced by the Italian national administrative order of 10 March 2020 (DM-10M20).RESULTS: 1109 dentists replied. To assess concerns and psychological responses the sample was divided into two groups based on the number of cases registered in their work area. In the first group were included all the responders working in the Italian regions that had more than 15.000 confirmed cases of COVID-19 as of April 29, 2020. The second group included responders working in the Italian regions that had less than 15,000 confirmed cases. The 45.2% of the respondents showed minimal anxiety, 34.5% showed mild anxiety, 13.9% showed moderate anxiety, while 6.4% showed a score indicative of a severe level of anxiety.CONCLUSIONS: The COVID-19-related emergency condition had a highly negative impact on dental practices in Italy. Those who completed the survey reported practice closure or reduction during the lockdown, and a high level of concern about the professional future for all dental practitioners. Concerns related to professional activity were accompanied by severe anxiety levels

Epidemiological Aspects and Psychological Reactions to COVID-19 of Dental Practitioners in the Northern Italy Districts of Modena and Reggio Emilia

The outbreak and diffusion of the Severe Acute Respiratory Syndrome-Coronavirus-2 (Sars-CoV-2) and COronaVIrus Disease 19 (COVID-19) have caused an emergency status in the health system, including in the dentistry environment. Italy registered the third highest number of COVID-19 cases in the world and the second highest in Europe. An anonymous online survey composed of 40 questions has been sent to dentists practicing in the area of Modena and Reggio Emilia, one of the areas in Italy most affected by COVID-19. The survey was aimed at highlighting the practical and emotional consequences of COVID-19 emergence on daily clinical practice. Specifically, it assessed dentists' behavioral responses, emotions and concerns following the Sars-CoV-2 pandemic restrictive measures introduced by the Italian national administrative order of 10 March 2020 (DM-10M20), as well as the dentists' perception of infection likelihood for themselves and patients. Furthermore, the psychological impact of COVID-19 was assessed by means of the Generalized Anxiety Disorder-7 test (GAD-7), that measures the presence and severity of anxiety symptoms. Using local dental associations (ANDI-Associazione Nazionale Dentisti Italiani, CAO-Commissione Albo Odontoiatri) lists, the survey was sent by email to all dentists in the district of Modena and Reggio Emilia (874 practitioners) and was completed by 356 of them (40%). All dental practitioners closed or reduced their activity to urgent procedures, 38.2% prior to and 61.8% after the DM-10M20. All reported a routinely use of the most common protective personal equipment (PPE), but also admitted that the use of PPE had to be modified during COVID-19 pandemic. A high percentage of patients canceled their previous appointments after the DM-10M20. Almost 85% of the dentists reported being worried of contracting the infection during clinical activity. The results of the GAD-7 (General Anxiety Disorder-7) evaluation showed that 9% of respondents reported a severe anxiety. To conclude, the COVID-19 emergency is having a highly negative impact on the activity of dentists practicing in the area of Modena and Reggio Emilia. All respondents reported practice closure or strong activity reduction. The perception of this negative impact was accompanied by feelings of concern (70.2%), anxiety (46.4%) and fear (42.4%). The majority of them (89.6%) reported concerns about their professional future and the hope for economic measures to help dental practitioners

Matriz tridimensional con potencial para regeneración ósea

79 páginasLas matrices poliméricas han recibido gran atención en los últimos años, ya que proporcionan un entorno temporal para el crecimiento y la interacción celular, además de la formación de la matriz extracelular, dando soporte a la formación de un nuevo tejido al actuar como un material prostético para regenerar tejido in vivo o como sustrato adhesivo celular para formar tejidos in vitro. El siguiente trabajo presenta la obtención de matrices tridimensionales de PLLA (ácido poliláctico) por medio del método salt leaching/gas foaming y la caracterización morfológica y mecánica de las mismas, mediante técnicas que incluyen hinchamiento, microscopia SEM, microscopia óptica y ensayos mecánicos de compresión.PregradoIngeniero(a) Biomédico(a

Histological changes in odontogenic parakeratinized keratocysts treated with marsupialization followed by enucleation

The purpose of this study was to evaluate whether marsupialization treatment induces changes in the histology of odontogenic keratocyst epithelium and to compare our experience with the literature. A retrospective revision of histological samples was performed. 5 patients with odontogenic keratocyst treated with marsupialization follow by enucleation were selected. Histologic evaluation analyzed the changes in the keratocyst epithelium after marsupialization in terms of type of keratinization, thickness of the epithelium and connective tissue, the presence of acanthosis, the presence and grade of fibrosis, the type and grade of inflammation and the presence and number of mitotic figures and daughter cysts. In our case series, a variation of para-keratinized into ortho-keratinized keratocyst was found in one case, and no significant increases were observed in the epithelium and capsule thickness, or even in the level of inflammation. However, we observed an increase in fibrosis and qualitative changes in inflammation type. Minor and major histological changes were associated with reduction in cyst volume, which resulted in a simpler and less invasive cystic enucleation after marsupialization