Goal Additive manufacturing, also known as 3D printing, has begun to play a significant role in the field of medical devices. This review aims to provide a comprehensive overview and classification of additively manufactured medical instruments for diagnostics and surgery by identifying medical and technical aspects. Methods A scientific literature search on additively manufactured medical instruments was conducted using the Scopus database. Results We categorized the relevant articles (71) by considering the novelty of each proposed instrument and its clinical application. Then, we analyzed the relevant articles by examining the reasons behind choosing additive manufacturing technology to produce instruments for diagnostics and surgery. Possible customization (27%) and Cost-effectiveness (23%) were the main reasons expressed. Technical specifications of the additive manufacturing technology and the material used were also analyzed, and a tendency of using material extrusion technology (35% of the applications) and polymeric materials (86% of the applications) was shown. Conclusions Additive manufacturing is opening the door to a new approach in the production of medical devices, which allows the complexity of their designs to be pushed to the extreme. However, we found that technical limitations need to be tackled and important aspects such as sterilization or debris contamination are still not considered to be relevant factors during the design and fabrication process. Keeping in mind the challenges of such a new field, additive manufacturing technology can be considered as a great opportunity to provide easy access to healthcare in developing countries as well as an important step toward patient-specific medicine.

Additive manufacturing of medical instruments : A state-of-the-art review

Haricot bean (Phaseolus vulgaris L.) starch from improved varieties was isolated by wet milling process and physico-chemical properties, pasting behavior and functional characteristics of bean flours and starches were analyzed. The functional and physical properties of the starches and flours including, swelling power and solubility pattern, color, pH, water and oil absorption capacity of bean starch-water suspension were examined. A rapid visco-analyzer and color flex spectrocolorimeter were used for evaluation of the pasting properties and color of the flours and starch extracts from beans respectively. Chemical composition of whole bean seed flours and starch isolates such as moisture, crude protein, crude fat, total ash, crude fiber, crude lipid, total carbohydrates, starch, phosphorus and amylose content were assessed. Results of analyses for pasting behavior, functional and physico-chemical properties indicated that significance differences (P < 0.05) among bean varieties existed. The factors which influence the pasting characteristics resulting to decrease in peak viscosity (PV), trough (MV) and final viscosity (FV) of starch compared to bean flour are attributed to the interaction of starch with the protein, fat, etc. which in their turn are dependent on the variety. These factors play an important role in governing the pasting properties of starch. The swelling power of the bean flour and starch isolates put them in the category of highly restricted-swelling starch. This characteristic is desirable for the manufacture of value-added products such as noodles and composite blends with cereals. The uses of starch from improved bean varieties to impart viscosity to local processed foods have remarkable potential in the context of East and Great Lakes Regions of Africa where bean consumption of such products are increasing.

Physico-chemical Properties, Pasting Behavior and Functional Characteristics of Flours and Starches from Improved Bean (Phaseolus vulgaris L.) Varieties Grown in East Africa

Thermal decomposition behaviour of dolomite sample has been studied by thermogravimetric (TG) measurements. Differential thermal analysis (DTA) curve of dolomite shows two peaks at 777·8°C and 834°C. The two endothermic peaks observed in dolomite are essentially due to decarbonation of dolomite and calcite, respectively. The TG data of the decomposition steps have also been analysed using various differential, difference-differential and integral methods, viz. Freeman-Carroll, Horowitz-Metzger, Coats-Redfern methods. Values of activation entropy, Arrhenius factor, and order of reaction have been approximated and compared. Measured activation energies vary between 97 and 147 kJ mol−1. The large fluctuation in activation energy is attributed to the presence of impurities such as SiO2, Al2O3, Fe2O3, Cl− etc in the samples. FTIR and XRD analyses confirm the decomposition reaction. SEM observation of the heat-treated samples at 950°C shows cluster of grains, indicating the structural transformation.

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Thermal decomposition of natural dolomite

M. Suarez

Papers

Synthesis of γ-titanium phosphate. study of the solids obtained by using water or acetone as washing agents

Characterization of monumental carbonate stones by thermal analysis (TG, DTG and DSC)

Thermodynamic treatment of proton/sodium(1+) ion exchange on .alpha.-titanium phosphate

Calorimetric determination of proton/sodium(1+) ion exchange on .alpha.-titanium phosphate

The preparation, characterisation and ion exchange properties of an amorphous titanium phosphate