Compressive strength evaluation of thin occlusal veneers from different CAD/CAM materials, before and after acidic saliva exposure.

Autor: Ille, Codruța, Moacă, Elena-Alina, Pop, Daniel, Goguță, Luciana, Opriș, Carmen, Pîrvulescu, Ioana Ligia, Avram, Liane, Faur, Andrei, Jivănescu, Anca
Předmět:
Zdroj: Odontology; Apr2023, Vol. 111 Issue 2, p360-374, 15p
Abstrakt: In the present study are depicted valuable observations for practitioners, obtained from an in vitro study which aims to evaluate the compressive strength of occlusal veneers fabricated from 3 type of restorative materials, before and after 1 month of acidic artificial saliva exposure (pH = 2.939). In this context, 90 extracted human molars were prepared to receive computer-aided design/computer-aided manufacturing (CAD/CAM) occlusal veneers. The restorative materials considered in this study were: Cerasmart; Straumann Nice and Tetric CAD. The occlusal veneers were designed, milled and cemented with an adhesive dual-cure resin cement. From all the extracted human molars, only sixty specimens were immersed in acidic artificial saliva, for 1 month, at 37 °C ± 1 °C and part of this specimens were also thermo-cycled, between 5 and 55 °C ± 2 °C, before compressive strength test. The results showed a lower compressive strength for both the samples exposed to acidic artificial saliva as well as for the samples exposed to acidic artificial saliva and thermo-cycled. Scanning electron microscopy (SEM) showed that after compressive strength, all the specimens non-exposed to acidic artificial saliva, present extensive cracks formation at the surface of the restorations, and after exposure to acidic artificial saliva for 1 month, the surface damage was characterized by longitudinal and profound fractures of the restoration, as well as the fracture of the tooth structure. Between CAD/CAM materials tested, nanoceramic resin shows more favorable fracture patterns, both before and after acidic artificial saliva exposure. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index