Several 3-dimensionally (3D) printed denture base resin materials designed for removable dentures and maxillofacial prostheses have recently been introduced, but studies on their properties are lacking. The purpose of this in vitro study was to assess the degree of conversion (DC%), Vickers hardness (VHN), crosslinking density (CD), tensile strength (TS), surface roughness (SR), and wettability (W) of two 3D printed denture base materials in comparison with a heat-polymerized polymethyl methacrylate (PMMA) control. Disk- (Ø15×3 mm) and dumbbell-shaped (International Organization for Standardization (ISO) 527-1 standard) specimens of two 3D printed denture base materials (V Print-dentbase) and (Optiprint Laviva) were printed, and PMMA specimens (Acrypol fast) were used as the control. DC% (n=5) was measured by Fourier Transform Infrared spectroscopy, VHN and CD (n=10) with a Vickers hardness tester, and TS (including modulus of elasticity-E and elongation-e, n=10) using a universal testing machine. SR parameters (Sa, Sq, Sz, Sdr, Sc, Sv, n=10) were measured with an optical profiler and water contact angles (θ) (apparent/θm and Young/θy, n=10) with a contact angle goniometer. Data were analyzed with t tests, the Mann-Whitney Rank Sum test, and 1-way ANOVA (α=.05). For DC%, the control was greater than the VP-dentbase (P<.05), with the other groups being statistically similar (P>.05). For VHN, the ranking was OP>VP and AF. Differences in CD were not significant. For TS and E the ranking was VP, AF>OP, with differences between VP and AF not significant. ε was zero for all materials. For SR parameters, the ranking was OPAF (for Sdr). No significant differences were found in θm and θy among the materials or between θm and θy per material (P>.05). The different chemical compositions of the 3DPs resulted in significant differences in some of the tested properties.

Air pollution is a major environmental risk to human health and wellbeing, and a major cause of mortality and morbidity worldwide. Particularly affected are the vulnerable populations of women, pregnant women, children, people with disabilities, and the elderly, who make up the majority of the world’s poor. In this work, we present a series of pieces of evidence linking the main air pollutants to chronic diseases in adults and children. The WHO has concluded that air pollution affects children’s neurodevelopmental and cognitive abilities, and can cause chronic diseases, such as childhood asthma and cancer. Epidemiological studies have shown significant effects caused by PM 2.5 and PM 10 particles toward mortality from different types of cancer. Finally, household air pollution increases the risk for a wide range of adverse cardiorespiratory, pediatric, and maternal health outcomes, particularly in poorer low- and middle-income countries.

One of the key arguments in favor of digitally produced complete dentures (CDs) is the requirement for less patient visits in comparison to the conventional workflow. However, it is not yet clear if this argument is accurate; nor, if indeed the insertion of the complete dentures is achieved in fewer appointments, how many are required. The purpose of this literature review was to investigate the reported number of required patient visits for the production of digitally fabricated CDs. An electronic search was performed in PubMed/MEDLINE using three groups of keywords: “complete dentures”, “CAD/CAM”, and “Appointments” with their alternative forms. Out of the initial 157 results, 36 articles were automatically selected utilizing exclusion keywords. After consensus between the two examiners, eight articles were finally analyzed and presented in a table. The majority (75%) of the reports came from institutions, and the average number of appointments up to complete denture insertion was 4.1, not always including try-in dentures. In this study, it can be concluded that, with a digital workflow, the insertion appointment is reached in fewer visits than the conventional five-visit procedure which is commonly taught in dental schools.