The CFP had a direct influence on the flexural strength and microstructural characteristics of both ZLS materials.

Objective: The purpose of this study is to evaluate the influence of the type of scanner and scanning direction on the accuracy of the final cast. Material and Methods: A partial master cast was used as a reference. A total of 128 scans were obtained and divided into two groups: the conventional method and the digital method. The digital group was divided into three groups: TRIOS 3, Omnicam and CS 3600. Each of these groups was subdivided according to the scanning direction, and each scan was overlaid on the digital reference cast to measure the trueness and precision of the procedures. Results: The overall precision values for the type of impression were 59.89 ± 13.08 mm for conventional and 13.42 ± 4.28 mm for digital; the values for trueness were 49.37 ± 19.13 mm for conventional and 53.53 ± 4.97 mm for digital; the scanning direction trueness values were 53.05 ± 4.36 mm for continuous and 54.03 ± 5.52 mm for segmented; and the precision values were 14.18 ± 4.67 mm for continuous and 12.67 ± 3.75 mm for segmented (p> 0.05). For the scanner type, the trueness values were 50.06 ± 2.65 mm for Trios 3, 57.45 ± 4.63 mm for Omnicam, and 52.57 ± 4.65 mm for Carestream; and those for precision were 11.7 ± 2.07 mm for Trios 3, 10.09 ± 2.24 mm for Omnicam, and 18.49 ± 2.42 mm for Carestream (p <0.05). Conclusions: The digital impression method is the most favorable method regarding precision; in terms of trueness, there are no differences between the types of impressions. KEYWORDS Conventional impression; Intra oral impression; Accuracy; Trueness.

Prosthetic rehabilitation can generate doubts among professionals regarding the type of material to choose when planning rehabilitation treatments. The establishment of reliable criteria for material selection raises frequent questions. This work presents a concept and an alternative and simplified proposal to paradigm shift in therapeutic approaches based on three trends in restorative dentistry: Biomimetics, the use of natural tissue as a restorative material, which offers potential for the recovery of the mechanical, aesthetic and biological properties of teeth; digital dentistry and CAD/CAM systems; and adhesive technology, which has undergone exponential and impressive advances. However, further studies are needed to evaluate the long-term performance of restorations in this variable field.  KeywordsAdhesion; Ceramics; Natural tooth; CAD/CAM; Oral rehabilitation; Biomimetics.

Objetivos: O presente estudo teve como objetivo identificar o impacto físico, psicológico, social e económico da pandemia de COVID-19 no quotidiano dos profissionais de saúde oral em Portugal. Métodos: Foi realizado um estudo observacional e transversal, sob a forma de questionário on-line com 32 perguntas, através da plataforma Google Forms, sendo o link depois partilhado com os profissionais de saúde oral, em Portugal, via e-mail e redes sociais. Resultados: O presente questionário obteve 364 respostas. Relativamente ao impacto da COVID-19 na prática clínica, 48.1% dos profissionais reportou que o número de horas de trabalho diminuiu e cerca de 74% referiu uma diminuição do seu rendimento mensal. Quando questionados acerca da afluência de pacientes, 43% indicou que diminuiu. Cerca de 30% dos inquiridos assinalou que a situação atual tem afetado a qualidade dos tratamentos efetuados. Quanto ao impacto da COVID-19 na saúde física e mental, os participantes relataram um aumento do cansaço e dos níveis de stress/ansiedade. A grande maioria (74.2%) admitiu levar o stress do trabalho para casa. Por fim, 92,3% tem conhecimento e aplica as regras de remoção dos equipamentos de proteção individual. Conclusões: O presente estudo concluiu que a pandemia de COVID-19 teve um claro impacto psicológico, social, físico e económico nos profissionais de saúde oral em Portugal. Portanto, sugerimos que as instituições nacionais de saúde pública devem transmitir a confiança de que os consultórios dentários são ambientes seguros, como também devem ser criados mecanismos de apoio psicológico e financeiro para os profissionais mais afetados.

Objective: To compare the reproduction trueness and precision of dental casts made by the conventional, milling and 3D printing techniques. Material and Methods: From an upper right side half-arch reference model (RM), 72 models were obtained and divided into three groups: conventional (CM), milled (MM) and printed (PM). All models were scanned and converted into standard tessellation language (.STL) files. The files were superimposed using 3D analysis software, and statistical analysis was performed using the root mean square (RMS) values obtained. The Shapiro-Wilk test was used to assess normality, and the Kruskal-Wallis test was used to compare groups (ρ < ⍺; ⍺ = 0.05). The Mann-Whitney U test was used for multiple comparisons among groups (ρ < ਕ; ਕ = 0.017). Results: There were significant differences in trueness (ρ = 0.000; ρ <0.001) and precision (ρ = 0.000; ρ < 0.001) among the three dental cast groups. Regarding trueness, CM presented better results, followed by MM and PM. Regarding precision, MM showed better results, followed by PM and CM, which did not show significant differences. Conclusions: For dental cast reproduction the conventional technique has the best trueness and the milling technique has the best precision.