Cement space measure cad/cam

STATEMENT OF PROBLEM: The influence of computer-aided manufacturing (CAM) parameters and settings on the outcomes of milled indirect restorations is poorly understood. PURPOSE: The purpose of this scoping review was to summarize the current CAM systems, parameters, and setting changes, and their effects on different outcomes of milled indirect restorations and aspects related to their manufacture. MATERIAL AND METHODS: The protocol of this review is available online (https://osf...

BACKGROUND: This study compared the marginal gaps of CAD/CAM lithium disilicate (LDS) crowns constructed using a contemporary and older scanner/milling unit combination at three different cement spaces. METHODS: Twenty-four undergraduate students prepared a Columbia model lower left first molar for an LDS crown in a simulated environment. From each crown preparation, one LDS crown was constructed using an E4D scanner/E4D milling unit (E4DS/E4DM) and TRIOS 3 scanner/Sirona inLab MC X5 milling unit (TRIO/MCX5) at cement space settings of 50, 100 and 200 μm...

OBJECTIVE: This in vitro study aimed to assess and contrast the marginal and internal adaptation of all-ceramic prefabricated veneers manufactured via the FirstFit guided tooth preparation system against all-ceramic veneers produced using the chairside Computer-Aided Design/Computer Aided Manufacture (CAD/CAM) system following identical guided preparation protocols. MATERIALS AND METHODS: Two main groups were included, with 16 lithium disilicate veneers per group...

PURPOSE: To compare the marginal and internal fit of monolithic zirconia (MZ) 3-unit fixed dental prostheses (FDPs) fabricated using two CAD/CAM workflows: full-chairside (FCH) and lab (LAB). MATERIALS AND METHODS: The right maxillary first premolar and first molar were prepared for MZ 3-unit FDPs on a typodont. CEREC Primescan digitized the typodont model 15 Omes. A total of 30 FDPs was fabricated using two processes: FCH (n = 15) and LAB (n = 15). FCH and LAB FDPs were designed using CEREC SW 4...

PURPOSE: The aim of this study was to investigate the influence of different convergence angles of abutment teeth and different cement spaces on internal adaptation of anterior fixed dental prostheses (FDPs) fabricated with a computer-aided design-computer-aided manufacturing (CAD-CAM) system. METHODS: Composite resin FDPs for 99 standardized maxillary central incisors were fabricated according to nine parameters: three total convergence angles (4 [DG4], 12 [DG12], and 20 degrees [DG20]) and three cement space settings (10 [CS10], 50 [CS50], and 90 µm [CS90])...

The long-term clinical success of indirect restorations highly depends on their marginal integrity. The cement space is an element that might affect the marginal integrity, but it can be altered during the configuring of the computer-assisted designing/computer-aided manufacturing (CAD-CAM) restoration. However, there is controversy in the literature regarding the effect of the cement space on the precision of zirconia crown marginal adaptation. The aim of this study was to measure the vertical marginal discrepancies between different cement thickness settings for CAD-CAM monolithic zirconia restorations...

BACKGROUND: Premature loss of primary molars can be treated with a band loop space maintainer (SM). However, fabricating a conventional band loop SM requires multiple clinical and laboratory procedures, which can potentially affect the accuracy of the SM. Moreover, the conventional SM is unable to fully restore masticatory function and maintain the vertical dimension of the edentulous space. In this current study, a fully digital workflow to fabricate a semi-rigid bridge SM made from polyetheretherketone (PEEK) has been described and evaluated for its clinical effectiveness...

Background Cement film space plays a significant role in achieving good adaptation of indirect restorations. The objective of this study is to investigate the effect of cement space parameters on the marginal adaptation of computer-aided design (CAD)/computer-assisted manufacturing (CAM) endocrowns. Methodology The coronal part of 10 freshly extracted human mandibular molars was reduced to a level of 1.5 mm above the cementoenamel junction (CEJ); then, root canal treatment was performed. On each tooth, four lithium disilicate endocrowns with different cement space parameters (40, 80, 120, and 160 µm) were designed and fabricated using CAD/CAM...

STATEMENT OF PROBLEM: Despite the acceptable physical properties of biocompatible high-performance polymer (BioHPP), little is known about the marginal accuracy and fracture strength of restorations made from this material. PURPOSE: This in vitro study assessed the marginal and internal adaptation and fracture strength of teeth restored with lithium disilicate (LD) ceramics and BioHPP monolithic crowns. MATERIAL AND METHODS: Twenty-four extracted premolars were prepared for complete coverage crowns and divided into 2 groups to receive pressed IPS e...

PURPOSE: The purpose of this in vitro study was to compare the accuracy of various 3D printers and a milling machine. MATERIALS AND METHODS: The die model was designed using CAD (Autodesk Inventor 2018 sp3). The 30 µm cement space was given to the die and the ideal crown of the mandibular left first molar was designed using CAD (ExoCAD). The crowns were produced using the milling machine (Imes-icore 250i) and the 3D printers (Zenith U, Zenith D, W11) and they were divided into four groups...

BACKGROUND AND PURPOSE: Provisional prostheses in restorations over several implants with immediate loading in completely edentulous patients increase the risk of frequent structural fractures. An analysis was performed of the resistance to fracture of prosthetic structures with cantilevers using graphene-doped polymethyl methacrylate (PMMA) resins and CAD-CAM technology. METHODS: A master model was produced with four implants measuring 4 mm in diameter and spaced 3 mm apart, over which 44 specimens representing three-unit fixed partial prostheses with a cantilever measuring 11 mm were placed...

OBJECTIVES: To evaluate and compare fracture resistance, translucency, and color reproducibility, as well as the effect of aging on the fracture load and color stability of novel monolithic CAD/CAM ceramics. MATERIALS AND METHODS: One hundred crowns of uniform thickness were milled from five ceramic blocks (n = 20): partially crystallized lithium disilicate (PLD) and fully crystallized lithium disilicate (FLD), lithium metasilicate (LMS), 4Y-TZP (SMZ), and 5Y-TZP (UMZ) monolithic zirconia...

BACKGROUND: This study aimed to evaluate the effect of virtual cement space and restorative materials on the fit of computer-aided design and computer-aided manufacturing (CAD-CAM) endocrowns. METHODS: A mandibular first molar tooth model received a butt joint margin endocrown preparation with a 2-mm occlusal thickness. Then, using a 3D-printing system, 120 copies of this prepared die were printed and assigned equally to three groups with different cement space settings (30, 60, and 120 μm) during the chairside CAD design...

PURPOSE: The first objective was to determine if the dual-curing of self-adhesive resin cement (SAC) with reduced light penetrating through zirconia had an effect on interfacial gap of zirconia restorations. The second purpose was to examine whether pretreatment methods for universal adhesive affected interfacial gap. The last aim was to compare the microhardness of SAC polymerized under different zirconia thicknesses. METHODS AND MATERIALS: This study evaluated self-adhesive resin cement (RelyX U200, 3M ESPE) after different pretreatment with universal adhesive (Single Bond Universal, 3M ESPE) under different polymerization conditions...

STATEMENT OF PROBLEM: Little is known about the fracture strength, retention, and adaptation of post-and-cores fabricated with novel tooth-colored materials by computer-aided design and computer-aided manufacturing (CAD-CAM). PURPOSE: The purpose of this in vitro study was to investigate the fracture strength, pull-out bond strength (POBS), and volume of luting agent of endodontically treated premolars restored with post-and-cores milled from different CAD-CAM materials...

This study was aimed to evaluate the fit of occlusal veneer restoration for two CAD/CAM materials with different cement space settings, using microCT scans. Sixty resin dies were made and divided into two groups (n=30) according to the materials, (I): Hybrid all-ceramic, and (II): zirconia-reinforced lithium silicate glass-ceramic. Each group was subdivided into three subgroups (n=10) according to the cement space parameters (30, 40, and 50 µm). Occlusal veneers for the six subgroups were milled. A circle with 20 different sections was placed at the center of every scanned specimen to measure four different locations (Occlusal, Axial, Marginal, and Absolute marginal discrepancy)...

This research aimed to evaluate the effect of cement space on the marginal discrepancy and retention of computer-aided design/computer-aided manufacturing (CAD/CAM) crowns. A total of 30 premolar Frasaco teeth were machined to receive crowns with cement spaces of 70, 90, and 110 μm. The marginal discrepancy measurements were done before and after cementation. Pull-off test was conducted using universal testing machine (UTM). Data was analyzed using two-way mixed ANOVA with post-hoc Bonferroni test and Kruskal-Wallis test...

STATEMENT OF PROBLEM: Agreement on the perfect virtual cement space value for computer-aided design and computer-aided manufacturing (CAD-CAM) implant-supported resin-ceramic crowns with the best marginal adaptation is lacking. The range of cement gap settings in some CAD design software programs is wide (0 to 200 μm), and manufacturer recommendations regarding the best cement gap setting for certain types of ceramics is not specific. PURPOSE: The purpose of this in vitro study was to evaluate the effect of virtual cement gap settings on the marginal fit of cemented resin-ceramic crowns on implant abutments...

STATEMENT OF PROBLEM: Although the 2D analysis of prosthesis cementation space has been popular, its correlation with volumetric comparison (3D data) of cement space is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the cement space in computer-aided design and computer-aided manufacturing (CAD-CAM) crowns of different materials and correlate 2D measurements of cement space with their corresponding 3D values (volume of cement space) by using microcomputed tomography (μCT) analysis of regions of interest...

STATEMENT OF PROBLEM: Polyetheretherketone (PEEK) can be used as a framework material for removable and fixed dental prostheses. However, information about the use of PEEK as a post-and-core restoration is scarce. PURPOSE: The purpose of this in vitro study was to evaluate the effect of different surface treatments on the push-out bond strength of milled polyetheretherketone posts to resin cement. MATERIAL AND METHODS: Sixty intact human maxillary central incisors were selected and endodontically treated, and standardized post spaces were prepared...