Ceramic Fragments and Metal-free Full Crowns: A Conservative Esthetic Option for Closing Diastemas and Rehabilitating Smiles

2013 ◽  
Vol 38 (6) ◽  
pp. 567-571 ◽  
Author(s):  
ME Miranda ◽  
KA Olivieri ◽  
FJ Rigolin ◽  
RT Basting

SUMMARY Dental ceramics make it possible to restore anterior teeth that have been esthetically compromised, presenting a high resistance to wear, biocompatibility, color stability, and low thermal conductivity. The development of different types of ceramic and techniques for adhesive cementation have made it possible to produce more conservative restorations without involving the healthy dental structure and with minimally invasive preparation, such as the bonding of ceramic fragments. The purpose of this article is to describe a clinical case in which diastemas were closed by using nanofluorapatite ceramic (e.max Ceram, Ivoclar-Vivadent) fragments on teeth 7 and 10 with minimal tooth preparation and metal-free ceramic crowns (e-max Ceram) reinforced with zirconia copings through a computer-aided design/computer-aided manufacturing system (Lava, 3M-ESPE) on teeth 8 and 9.

2013 ◽  
Vol 07 (S 01) ◽  
pp. S115-S118 ◽  
Author(s):  
Rafael Ferrone Andreiuolo ◽  
Carlos Eduardo Sabrosa ◽  
Katia Regina H. Cervantes Dias

ABSTRACTThe use of bi-layered all-ceramic crowns has continuously grown since the introduction of computer-aided design/computer-aided manufacturing (CAD/CAM) zirconia cores. Unfortunately, despite the outstanding mechanical properties of zirconia, problems related to porcelain cracking or chipping remain. One of the reasons for this is that ceramic copings are usually milled to uniform thicknesses of 0.3-0.6 mm around the whole tooth preparation. This may not provide uniform thickness or appropriate support for the veneering porcelain. To prevent these problems, the dual-scan technique demonstrates an alternative that allows the restorative team to customize zirconia CAD/CAM frameworks with adequate porcelain thickness and support in a simple manner.


2016 ◽  
Vol 41 (6) ◽  
pp. 666-671 ◽  
Author(s):  
C Gillette ◽  
R Buck ◽  
N DuVall ◽  
S Cushen ◽  
M Wajdowicz ◽  
...  

SUMMARY Objective: To evaluate the significance of reduced axial wall height on retention of adhesively luted, all-ceramic, lithium disilicate premolar computer-aided design/computer-aided manufacturing (CAD/CAM) crowns based on preparations with a near ideal total occlusal convergence of 10°. Methods: Forty-eight recently extracted premolars were randomly divided into four groups (n=12). Each group received all-ceramic CAD/CAM crown preparations featuring axial wall heights of 0, 1, 2, and 3 mm, respectively, all with a 10° total occlusal convergence. Scanned preparations were fitted with lithium disilicate all-ceramic crowns that were luted with a self-etching resin cement. Specimens were tested to failure at a 45° angle to the tooth long axis with failure load converted to megapascals (MPa) based on the measured bonding surface area. Mean data were analyzed using analysis of variance/Tukey's post hoc test (α=0.05). Results: Lithium disilicate crowns adhesively luted on preparations with 0 axial wall height demonstrated significantly less failure resistance compared with the crowns luted on preparations with axial wall heights of 1 to 3 mm. There was no failure stress difference between preparations with 1 to 3 mm axial wall height. Conclusions: Under conditions of this study, adhesively luted lithium disilicate bicuspid crowns with a total occlusal convergence of 10° demonstrated similar failure resistance independent of axial wall height of 1 to 3 mm. This study provides some evidence that adhesion combined with an ideal total occlusal convergence may compensate for reduced axial wall height.


2010 ◽  
Vol 4 (2) ◽  
Author(s):  
Zhichao Li ◽  
Weilong Cong ◽  
Matthew Stanco ◽  
Zhigang Xu ◽  
Zhijian Pei ◽  
...  

Commercially available dental computer aided design/computer aided manufacture (CAD/CAM) systems usually use abrasive machining processes such as diamond grinding and milling. One of the major disadvantages of abrasive machining processes is subsurface cracks. In the present paper, rotary ultrasonic machining (RUM) technology is introduced into machining of alumina dental ceramics. The subsurface cracks are observed under scanning electron microscope. Effects of ultrasonic vibration on the subsurface cracks are also investigated. Results show that RUM is a very promising process to significantly reduce subsurface cracks in CAD/CAM of dental ceramics.


2021 ◽  
Vol 6 (11) ◽  

Background: Most dental trauma in children and adolescents involve anterior tooth fractures. Advancements in ceramics technology and in computer-aided design/computer-aided manufacturing (CAD/CAM) systems, have led to the technological abilities to produce single all-ceramic crowns with high biocompatibility, esthetics, and optimal mechanical properties. However, there is no information regarding the use of this technique in children. Case report:Treatment of extensive crown fractures on an 11 years old patient using a chairside CAD/CAM technology. The teeth were scanned and the restorations were fabricated using the manufacturing unit of the CAD/CAM system and glazed to the appropriate tooth color. At a follow up visits the restorations kept their strength and esthetic appearance (one year follow up). Conclusion: The digital restoration treatment is especially suitable for treating children with dental trauma. It has the advantage of better esthetic, functional and durable results compering to conventional restorations, and it often requires only a single session.


2021 ◽  
Vol 11 (20) ◽  
pp. 9399
Author(s):  
Dong-Geun Lee ◽  
Keunbada Son ◽  
Kyu-Bok Lee

The purpose of this study was to evaluate the accuracy of intraoral scanners in 10 abutments (five premolars and five molars) obtained in a dental clinic and to analyze the impacts of the volume and area of abutments on scanning accuracy. Abutment casts were scanned five times with a 3D contact scanner (DS10; Renishaw plc). The five scan files were lined up and then merged, and one high-resolution computer-aided design reference model (CRM) was obtained. To obtain a computer-aided design test model (CTM), three types of intraoral scanners (CS3600 (Carestream Dental), i500 (Medit), and EZIS PO (DDS)) and one type of laboratory scanner (E1; 3Shape) were employed. Using 3D analysis software (Geomagic control X; 3D Systems), the accuracy of the scanners was evaluated, including optimal overlap by optimal alignment. The conformity of the overlapped data was calculated by the root mean square (RMS) value, using the 3D compare function for evaluation. As for statistical analysis, testing was conducted, using one-way and two-way ANOVA and the Tukey HSD test (α = 0.05) for the comparison of the groups. To analyze the correlations of the volume and area of the abutments with accuracy, Pearson’s correlation analysis was conducted (α = 0.00625). Both premolar and molar abutments showed a lower RMS value on the laboratory scanner than on the intraoral scanners, and the RMS value was lower in premolars than in molars (p < 0.001). In the intraoral scanner group, CS3600 showed the best accuracy (p < 0.001). There were significant positive correlations for the volume and area of the abutments with accuracy (p < 0.001). The type, volume, and area of the clinically applicable abutments may affect the accuracy of intraoral scanners; however, the scanners used in the present study showed a clinically acceptable accuracy range, regardless of the type of abutment.


This chapter investigates the materials used in dentistry today. This includes the properties of dental materials, amalgam, and composite resins. Enamel and dentine bonding are discussed, along with dentine-adhesive systems, glass ionomers and composite-based products, and cements. Impression materials and techniques are considered, along with casting alloys, wrought alloys, dental ceramics, and computer-aided design (CAD) and computer-aided manufacture (CAM). The chapter concludes with a look at denture materials, from acrylic resins to rebasing, and the safety of dental materials.


2019 ◽  
Vol 45 (4) ◽  
pp. 416-425
Author(s):  
LH Raposo ◽  
PS Borella ◽  
DC Ferraz ◽  
LM Pereira ◽  
MS Prudente ◽  
...  

Clinical Relevance Marginal misfit of monolithic lithium disilicate ceramic crowns obtained from a chairside computer-aided design/computer-aided manufacturing system is affected after successive millings using a single diamond bur set. This fact can be critical for the longevity of indirect restorations. SUMMARY Objectives: This laboratory study aimed to assess the effect of successive crown millings on the marginal misfit of monolithic full-ceramic restorations obtained from two lithium disilicate systems, with a single diamond bur set used for each material in a chairside computer-aided design/computer-aided manufacturing (CAD/CAM) unit. Methods and Materials: Initially, 36 standardized composite resin dies were produced by additive manufacturing from a three-dimensional model of a right mandibular first molar with full-crown preparation generated in CAD software. Individual ceramic crowns were obtained in a chairside CAD/CAM unit (CEREC MC XL) for each composite resin die according to the ceramic system (IPS e.max CAD and Rosetta SM; n=18). Two new diamond burs were used as a set for obtaining the crowns in each experimental group (ceramic systems), and the milling periods were defined after three crown millings (T0-T6), when the diamond bur set of each system was removed for morphologic characterization using scanning electron microscopy (SEM). The marginal misfit of the crowns was assessed through coronal and sagittal micro-tomographic sectioning, in the vertical and horizontal directions of the ceramic crowns seated on their respective resin dies. The collected data were tabulated and subjected to one-way analysis of variance and Tukey's honestly significant difference test (α=0.05). Results: SEM images showed changes in the superficial morphology of the diamond bur sets, with progressive loss of the diamond granules after the successive millings of crowns for both experimental groups. Significant differences were detected in the marginal misfit of the crowns from both ceramic systems at the different milling periods (p&lt;0.001). Conclusions: Diamond burs deteriorated after successive crown millings for both lithium disilicate ceramic systems. The marginal misfit of the crowns obtained increased with the successive use of the CAD/CAM diamond bur set employed for milling each ceramic material. In addition, new milling of full lithium disilicate ceramic crowns can be inappropriate after 11 successive millings for IPS e.max CAD and 12 for Rosetta SM, due to the increased marginal misfit observed under the parameters tested.


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