The aim of this study was to evaluate and compare the fracture resistance of a single-unit fixed prosthesis, using a CAD/CAM PMMA material and two printed materials (3DPPa and 3DPPb). A typodont with a specific preparation for a full crown was used; a digital impression was made with a state-of-the-art scanner (PrimeScan^TM, Dentsply-Sirona^TM, New York, NY, USA), and a full coverage restoration was designed using a biogeneric design proposal by means of specific software (InLAB 22.1, Dentsply-Sirona, NY, USA). Sixty crowns were prepared, divided into three groups according to the material: 3DPPa (n = 20), 3DPPb (n = 20), both 3D-printed from the .STL file with a resolution of 50 μm, and PMMA (n = 20) milled-derived, which were subjected to a thermocycling process. A universal testing machine (Universal/Tensile Testing Machine, Autograph AGS-X Series) with integrated software (TRAPEZIUM LITE X) equipped with a 20 kN load cell was used to determine the fracture resistance. Significant differences were found by Kruskal–Wallis test and multiple comparisons (p < 0.05) in fracture resistance between materials. The fracture resistance for the PMMA material was higher, and the standard deviation was lower (x = 1427.9; sd = 36.9 N) compared to the 3DPPa (x = 1231; sd = 380.1 N) and 3DPPb (x = 1029.9; sd = 166.46 N) prints. The restorations from the milled-derived group showed higher average fracture resistance than the provisional restorations obtained from the printed groups. However, the results demonstrated that all three materials analyzed in single-unit restorations are capable of withstanding the average masticatory forces.

Introduction: The carbon neutral standard, or also known as carbon neutral or “zero net emissions” standard, aims to balance the greenhouse gas emissions released into the atmosphere with the elimination or compensation of the same amount of emissions. In many countries, this standard has been implemented with certain policies and measures to move towards carbon neutrality in different international agreements. Said policies include actions such as the promotion of renewable energies, energy efficiency, use of renewable materials, etc. Objective: to determine the importance of Carbon Neutral model in dental clinics. Materials and Methods: In this article, a review of the literature about the Carbon Neutral Standard and its impact on Companies and Dentistry was carried out, using scientific articles and other research documents from the Scopus, Google Scholar, Scielo databases. and the website of the Ministry of the Environment of Ecuador. Conclusion: The carbon neutral standard promotes environmental awareness and responsibility in companies, reducing emissions, energy and water consumption, and also minimizing the consumption of single-use plastics. Dental offices can be polluting, but the implementation of reusable supplies benefits the environment and saves money. In Ecuador, carbon neutral certifications endorsed by the National Environmental Authority can be obtained.