Publications by authors named "Munir Demirel"
Objective: To evaluate the effect of build orientation on the fabrication trueness and fit of additively manufactured 2-piece zirconia abutments when compared with those manufactured subtractively in 3 mol% and 4 mol% yttria-stabilized zirconia (3Y-TZP and 4Y-TZP).
Methods: A titanium-base (Ti-base) abutment was digitized with a scan body and an industrial scanner to design a 2-piece zirconia abutment with a 50 µm cement gap. This design was used to manufacture zirconia abutments additively in different orientations (0-degree, AM-0; 15-degree, AM-15; 30-degree, AM-30; 45-degree, AM-45; 180-degree, AM-180) and subtractively from 3Y-TZP and 4Y-TZP (SM-3 and SM-4) (n=5).
Article Synopsis
- The study examined how the design of implant analogs and the thickness of printing layers influence the accuracy of digitally made casts compared to traditional stone casts.
- Results indicated that the type of analog used and the layer thickness significantly affected both linear and angular deviations, with S analogs generally demonstrating better accuracy than N analogs.
- The findings suggest that using S-50 analogs might provide greater positional accuracy than other groups, emphasizing the importance of design and manufacturing methods in dental applications.
Statement Of Problem: Inorganic fillers can be incorporated into additively manufactured (AM) resins to improve their properties, and a ceramic composite concentrate has been recently marketed for this purpose. However, knowledge on the printability of AM resins modified with this concentrate is lacking.
Purpose: The purpose of this in vitro study was to evaluate the manufacturing trueness and internal fit of AM crowns in a dental resin modified with a commercially available ceramic composite concentrate.
Objectives: To evaluate the fabrication trueness of additively manufactured maxillary definitive casts with various tooth preparations fabricated with different 3-dimensional (3D) printers and print orientations.
Methods: A maxillary typodont with tooth preparations for a posterior 3-unit fixed partial denture, lateral incisor crown, central incisor and canine veneers, first premolar and second molar inlays, and a first molar crown was digitized with an industrial scanner. This scan file was used to fabricate definitive casts with a digital light processing (DLP) or stereolithography (SLA) 3D printer in different orientations (0-degree, 30-degree, 45-degree, and 90-degree) (n = 7).
This study aimed to evaluate the dimensional stability of maxillary diagnostic casts fabricated from a biobased model resin, which consists of 50% renewable raw materials for sustainable production, a model resin, and stone, over one month. A master maxillary stone cast was digitized with a laboratory scanner to generate a reference file. This master cast was also scanned with an intraoral scanner to additively manufacture casts with a biobased model resin (BAM) and a model resin (AM).
View Article and Find Full Text PDFObjectives: To evaluate the positional accuracy of implant analogs in biobased model resin by comparing them to that of implant analogs in model resin casts and conventional analogs in dental stone casts.
Methods: Polyvinylsiloxane impressions of a partially edentulous mandibular model with a single implant were made and poured in type IV dental stone. The same model was also digitized with an intraoral scanner and additively manufactured implant casts were fabricated in biobased model resin (FotoDent biobased model) and model resin (FotoDent model 2 beige-opaque) (n = 8).
Statement Of Problem: Additive (AM) and subtractive (SM) manufacturing have become popular for fabricating occlusal devices with materials of different chemical compositions. However, knowledge on the effect of material and antagonist type on the wear characteristics of occlusal devices fabricated by using different methods is limited.
Purpose: The purpose of this in vitro study was to evaluate the effect of material and antagonist type on the wear of occlusal devices fabricated by using conventional manufacturing, AM, and SM.
Objectives: To evaluate whether post-milling firing and material type affect the fabrication trueness and internal fit of lithium disilicate crowns.
Methods: A prefabricated cobalt chromium abutment was digitized to design a mandibular right first molar crown. This design file was used to fabricate crowns from different lithium disilicate ceramics (nano-lithium disilicate (AM), fully crystallized lithium disilicate (IN), advanced lithium disilicate (TS), and lithium disilicate (EX)) (n = 10).
Objectives: To evaluate the effect of different data acquisition methods on the trueness and precision of mandibular complete-arch implant scans.
Methods: An edentulous polyurethane master mandibular model with 6 implants was digitized by using an industrial-grade blue light scanner (ATOS Core 80 5MP) to obtain a master standard tessellation language (MSTL) file. The master model was also digitized by using either direct digital workflow with a stereoscopic camera (iCam 4D (IM)) or intraoral scanners (CEREC Primescan (PS) and Trios 4 (T4)) or indirect digital workflow with laboratory scanners (inEos X5 (X5) and CARES 7 (S7)) to obtain test-scan STLs (n = 10).
Statement Of Problem: Additively manufactured resins indicated for fixed definitive prostheses have been recently marketed. However, knowledge on their wear and fracture resistance when fabricated as screw-retained, implant-supported crowns and subjected to artificial aging is limited.
Purpose: The purpose of this in vitro study was to evaluate the volume loss, maximum wear depth, and fracture resistance of screw-retained implant-supported crowns after thermomechanical aging when fabricated using additively and subtractively manufactured materials.
Objectives: To evaluate the fabrication trueness and internal fit of hybrid abutment crowns fabricated by using additively and subtractively manufactured restorative materials.
Methods: A maxillary first premolar crown with a screw access channel was designed onto a digitized master titanium base abutment. This file was used to fabricate 40 crowns additively (Crowntec (CT) and VarseoSmile Crown Plus (VS)) or subtractively (Brilliant Crios (BC) and Vita Enamic (EN)) (n = 10).
Purpose: To investigate the color stability, translucency, biaxial flexural strength (BFS), and reliability of nano-lithium disilicate and fully crystallized lithium disilicate after thermal cycling and to compare with those of a commonly used lithium disilicate.
Materials And Methods: Three lithium disilicate glass-ceramics were used to prepare disk-shaped specimens (ø:12 mm, thickness: 1.2 mm) from A2 shaded HT blocks (Amber Mill, AM; Initial LiSi Block, IN; IPS e.
Objective: To compare the color stability, translucency, and biaxial flexural strength (BFS) of differently glazed advanced lithium disilicate (ALDS) with those of lithium disilicate (LDS) and zirconia-reinforced lithium silicate (ZLS) after coffee thermocycling.
Materials And Methods: Forty disk-shaped specimens were prepared from three lithium silicate based materials (CEREC Tessera, ALDS; IPS e.max CAD, LDS; Vita Suprinity, ZLS).
The aim of this study was to compare the load-to-failure resistance and optical properties of nano-lithium disilicate (NLD) with lithium disilicate (LDS) and zirconia-reinforced lithium silicate (ZLS) in different aging processes. Thirty crowns were milled from NLD, LDS, and ZLS (n = 10). All crowns were subjected to thermomechanical aging and loaded until catastrophic failure.
View Article and Find Full Text PDFObjectives: To evaluate the effect of printing orientation on the fracture strength of 3-unit interim fixed dental prostheses fabricated by using additive manufacturing and to compare with those fabricated by subtractive manufacturing after thermomechanical aging.
Materials And Methods: A 3-unit fixed dental prosthesis was designed by using a dental design software (exocad DentalCAD 2.2 Valetta) in standard tessellation language (STL) format.
Objectives: This study evaluated the surface integrity of two types of diamond burs and their effect on the roughness of different CAD/CAM materials.
Materials And Methods: CAD/CAM materials, Vita Mark II (VM), IPS e.max CAD (EM), Celtra Duo (CD), G-Ceram (GC), and Lava Ultimate (LU) blocks were milled with CEREC MCXL.
Statement Of Problem: Partially stabilized zirconia has been introduced as a more translucent iteration. However, knowledge of the effect of the thickness of partially stabilized zirconia on the microhardness of resin cement is sparse.
Purpose: The purpose of this in vitro study was to evaluate the effect of thickness and material type on the translucency of partially stabilized zirconia and the microhardness of the resin cement polymerized beneath.
Statement Of Problem: Zirconia is a widely used restorative material, yet its white color does not meet esthetic requirements and coloring is needed. However, the effects of different durations of coloring have not been thoroughly investigated.
Purpose: The purpose of this in vitro study was to evaluate the effects of coloring liquid immersion of different durations on the flexural strength, Vickers hardness, and color of zirconia.