CAD/CAM in modern orthopedic dentistry

Department of Orthopedic Dentistry, Nicolae Testemitanu State University of Medicine and Pharmacy of the Republic of MoldovaIntroduction. CAD/CAM (Computer - aided Design, Computer - aided manufacturing) is a perspective branch of digital dentistry. The whole СAD/CAM technological process from taking impressions until fixation is performed by chairside and can take only one visit. According to polls (2016), 89% of dentists consider that CAD/CAM technology has to replace conventional process of modelling and manufacturing of prosthetic constructions in the nearest future. Aim of the study. to analyze technological possibilities of СAD/CAM in orthopedic dentistry, to reveal advantages and disadvantages of CAD/CAM technology on the example of a clinical case. Materials and methods. Was carried out a review of the publications of the last 10 years on the selected theme using PubMed system. According to a key phrase "CAD/CAM" 1862 publications were found, 80 publications were selected and analyzed. Research includes data from 20 publications. Examination of a patient at the age of 32 years with partial defect of solid tissues of lateral teeth of the maxilla was performed. Defect was treated with the help of zirconium crowns manufactured by means of CAD/CAM technology. Results.The analysis of literature allowed to define the main advantages of CAD/CAM technology: 1) accuracy of marginal fit and occlusal contacts; 2) high esthetics; 3) concept of one-visit dentistry; 4) decrease of human factor; 5) stability and predictability of treatment. Presented clinical case confirms mentioned advantages of CAD/CAM technology. According to five sources, marginal discrepancy of the CAD/CAM crowns varies from 30 to 60 microns. At the same time traditional full ceramic crowns have an average discrepancy 90 microns. Researches demonstrate maintaining of 95-98% of CAD/CAM crowns for the 6-year period of clinical observation (R. Van Noort, 2012, M. Fages, 2017, Alqahtani, 2017). The analysis of literature revealed fact that rather small significance is attached to applying of CAD/CAM digital workflow in treatment of handicapped people and other categories. Possibility to minimize the number of visits for this group of patients is the greatest advantage. Were defined the following shortcomings of CAD/CAM technology: 1) high cost; 2) increased material consumption; 3) limitations in several types of prosthetic constructions. Conclusions. 1. The analysis of literature showed that CAD/CAM the technology has large prospects in modern dentistry due to constant perfecting. 2. The quality of CAD/CAM crowns and bridges surpasses the quality of conventional constructions of the same type. However, partial and complete CAD/CAM dentures, as well as some other constructions, still have lack of precision

Quantitative Expression of C-Type Lectin Receptors in Humans and Mice

C-type lectin receptors, their adaptor molecules and S-type lectins (galectins) are involved in the recognition of glycosylated self-antigens and pathogens. However, little is known about the species- and organ-specific expression profiles of these molecules. We therefore determined the mRNA expression levels of Dectin-1, MR1, MR2, DC-SIGN, Syk, Card-9, Bcl-10, Malt-1, Src, Dec-205, Galectin-1, Tim-3, Trem-1, and DAP-12 in 11 solid organs of human and mice. Mouse organs revealed lower mRNA levels of most molecules compared to spleen. However, Dec-205 and Galectin-1 in thymus, Src in brain, MR2, Card-9, Bcl-10, Src, and Dec-205 in small intestine, MR2, Bcl-10, Src, Galectin-1 in kidney, and Src and Galectin-1 in muscle were at least 2-fold higher expressed compared to spleen. Human lung, liver and heart expressed higher mRNA levels of most genes compared to spleen. Dectin-1, MR1, Syk and Trem-1 mRNA were strongly up-regulated upon ischemia-reperfusion injury in murine kidney. Tim3, DAP-12, Card-9, DC-SIGN and MR2 were further up-regulated during renal fibrosis. Murine kidney showed higher DAP-12, Syk, Card-9 and Dectin-1 mRNA expression during the progression of lupus nephritis. Thus, the organ-, and species-specific expression of C-type lectin receptors and galectins is different between mice and humans which must be considered in the interpretation of related studies

Striking augmentation of hematopoietic cell chimerism in noncytoablated allogeneic bone marrow recipients by flt3 ligand and tacrolimus

The influence of granulocyte-macrophage colony-stimulating factor (GM- CSF) and the recently identified hematopoietic stem-progenitor cell mobilizing factor flt3 ligand (FL) on donor leukocyte microchimerism in noncytodepleted recipients of allogeneic bone marrow (BM) was compared. B10 mice (H2b) given 50 x 106 allogeneic (B10.BR [H2(k)]) BM cells also received either GM-CSF (4 μg/day s.c.), FL (10 μg/day i.p.), or no cytokine, with or without concomitant tacrolimus (formerly FK506; 2 mg/kg) from day 0. Chimerism was quantitated in the spleen 7 days after transplantation by both polymerase chain reaction (donor DNA [major histocompatibility complex class II; I-E(k)]) and immunohistochemical (donor [I-E(k+)] cell) analyses. Whereas GM-CSF alone significantly augmented (fivefold) the level of donor DNA in recipients' spleens, FL alone caused a significant (60%) reduction. Donor DNA was increased 10-fold by tacrolimus alone, whereas coadministration of GM-CSF and tacrolimus resulted in a greater than additive effect (28-fold increase). A much more striking effect was observed with FL + tacrolimus (>125-fold increase in donor DNA compared with BM alone). These findings were reflected in the relative numbers of donor major histocompatibility complex class II+ cells (many resembling dendritic cells) detected in spleens, although quantitative differences among the groups were less pronounced. Evaluation of cytotoxic T lymphocyte generation by BM recipients' spleen cells revealed that FL alone augmented antidonor immunity and that this was reversed by tacrolimus. Thus, although FL may potentiate antidonor reactivity in nonimmunosuppressed, allogeneic BM recipients, it exhibits potent chimerism-enhancing activity when coadministered with recipient immunosuppressive therapy. This property of FL may offer considerable potential for the augmentation of microchimerism, with therapeutic implications for organ allograft survival and tolerance induction

Guidelines for the Systematic Selection of Virtual Reality Hardware for Learning Factories

The development and operation of physical as well as virtual learning factories are complex and costly activities. For a competency-oriented development of learning factories the (virtual) factory hardware must be tailored to the curriculum and the underlying competencies. With virtual learning factories - or virtual learning scenarios in general - there are two aspects which need to be considered. Firstly, the virtual learning environment itself must be designed. This aspect contains e.g., the selection of suitable machines and production equipment. Secondly, the used virtual reality hardware must be chosen additionally for virtual learning environments. Learning factories normally undergo a continuous improvement process regarding their curriculum and offered content. Therefore, the selection of virtual reality (VR) hardware can be a challenging aspect for learning factory operators since the decision should not only be suitable for the current situation but is also a strategic decision. This publication explains and offers a guideline how learning factory operators can select suitable virtual reality hardware components in a systematic and structured way and which aspects should be considered to identify the most suitable configuration