Effect of Different Wax Pattern Manufacturing Techniques on the Marginal Fit of Lithium Disilicate Crowns.

Purpose: The present study evaluated the marginal gap of lithium disilicate crowns fabricated through three different wax pattern techniques; Conventional, Milling and 3D-printing. Materials and Methods: Thirty stone models were replicated from a stainless-steel model representing a prepared tooth; ten were sent to make conventional wax patterns while the remaining were sent to a digital dental scanner. The computer aided design was completed and STL (Standard Tessellation Language) files were sent to either milling or 3D-printing machines.

Color stability of 3D-printed denture resins: effect of aging, mechanical brushing and immersion in staining medium.

Purpose: This study evaluated and compared the color stability of 3D-printed and conventional heat-polymerized acrylic resins following aging, mechanical brushing, and immersion in staining medium.

Materials And Methods: Forty disc-shaped specimens (10 mm in diameter and 3 mm thick) were prepared from two 3D-printed [DentaBASE (DB) and Denture 3D+ (D3D)] and one conventional polymethylmethacrylate (PMMA) denture materials. The specimens were thermo-cycled, subjected to mechanical brushing, and were immersed in either coffee, lemon juice, coke, or artificial saliva (AS) to simulate one and two years of oral use.