Effect of brushing and thermocycling on the shade and surface roughness of CAD-CAM ceramic restorations

Objective. To determine the influence of the home bleaching agent, Opalescence PF, on the surface roughness and microhardness of glazed glassy matrix CAD-CAM ceramics. Materials and Methods. The 28 sintered leucite- and lithium disilicate-reinforced ceramic specimens (IPS Empress CAD and IPS e.max CAD) were divided into control and bleached groups. The home bleaching agent was applied to specimens of bleached groups for 7 days. The surface roughness and microhardness of all specimens were measured. A scanning electron microscope was used to evaluate the surface properties. The data were statistically analyzed by two-way ANOVA. Results. The control e.max CAD showed the lowest surface roughness values. For both Empress and e.max CAD, surface roughness was significantly higher for the bleached group (p<0.05). No significant differences in microhardness were observed. Conclusions. According to our study, patients should be careful when using home bleaching agents because whitening agents can affect the mechanical properties of full ceramic restorations like e.max CAD and Empress CAD. Ceramic polishing may be required in clinical situations where ceramic restorations are accidentally exposed to bleaching gels.

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Comparative In-Vitro Wear Resistance and Surface Roughness of Chairside CAD/CAM Materials

Journal of Dentistry & Oral Disorders ◽

10.26420/jdentoraldisord.2017.1062 ◽

2017 ◽

Vol 4 (3) ◽

Author(s):

Mohamed Shafter

Keyword(s):

Surface Roughness ◽

Wear Resistance ◽

Cad Cam

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Surface Roughness of Two CAD/CAM Restorative Materials as Affected by Chewing Simulation v1

10.17504/protocols.io.b3jiqkke ◽

2022 ◽

Author(s):

eaeldwakhly not provided

Keyword(s):

Surface Roughness ◽

Computer Aided Design ◽

Surface Characteristics ◽

Ceramic Materials ◽

Study Groups ◽

Significance Level ◽

Chewing Simulation ◽

Computer Aided ◽

Cad Cam ◽

The Individual

This study was conducted to assess the surface characteristics in terms of roughness of two CAD/CAM (Computer-Aided-Design/Computer-Aided Manufacturing)restorative material spre and post chewing simulation exposure. Methods: Specimens were prepared from two CAD/CAM ceramic materials: Cerec Blocs C and IPS e-max ZirCAD. A total of 10 disks were prepared for each study group. 3D optical noncontact surface profiler was used to test the surface roughness (ContourGT, Bruker, Campbell, CA, USA). A silicone mold was used to fix the individual samples using a self-curing resin. Surface roughness (SR) was examined pre and post exposure to chewing simulation. 480,000 simulated chewing cycles were conducted to mimic roughly two years of intraoral clinical service. The results data was first tested for normality and equal variance (Levene’s test >0.05) then examined with paired and independent sample t-test at a significance level of (p < 0.05). Results:The two CAD-CAM materials tested exhibited increased surface roughness from baseline. The highest mean surface roughness was observed in Cerec blocs C group after chewing simulation (2.34 µm± 0.62 µm). Whereas the lowest surface roughness was observed in IPS e.max ZirCAD group before chewing simulation (0.42 µm± 0.16 µm). Both study groups exhibited significantly different surface roughness values (p< 0.05). There was a statistically higher surface roughness values after the chewing simulation in Cerec blocs C when compared to IPS e.max ZirCAD groups (p = 0.000).Conclusion:Even though both tested CAD/CAM materials differ in recorded surface roughness values, results were within clinically accepted values.

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Effect of CAD-CAM tool deterioration on the trueness of ceramic restorations

Journal of Prosthetic Dentistry ◽

10.1016/j.prosdent.2020.09.035 ◽

2020 ◽

Author(s):

Khaled Q. Al Hamad ◽

Rama B. Al Rashdan ◽

Bashar A. Al Rashdan ◽

Firas A. Al Quran

Keyword(s):

Cad Cam ◽

Ceramic Restorations

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Evaluation of Polishing Systems for CAD/CAM Polymer-Infiltrated Ceramic-Network Restorations

Operative Dentistry ◽

10.2341/20-006-l ◽

2021 ◽

Author(s):

CA Jurado ◽

A Tsujimoto ◽

H Watanabe ◽

NG Fischer ◽

JA Hasslen ◽

...

Keyword(s):

Surface Roughness ◽

Computer Aided Design ◽

Dental Students ◽

Faculty Members ◽

Dental School ◽

Control Group ◽

Significant Difference ◽

Computer Aided ◽

Cad Cam ◽

A Company

SUMMARY Objective: The purpose of this study was to evaluate the effectiveness of five different polishing systems on a computer-aided design and computer-aided manufacturing (CAD/CAM) polymer-infiltrated ceramic-network restoration with nanoscale assessment using atomic force microscopy (AFM) and visual assessment performed by dental school senior students and faculty members. Method: Forty-eight full coverage crowns were milled out of polymer-infiltrated ceramic-network CAD/CAM blocks (Vita Enamic) for polishing with one company proprietary, two ceramic and two composite polishing systems. The prepared crowns were divided into six groups: (1) no polishing (control); (2) polishing with Vita Enamic Polishing Kit (VEna); (3) polishing with Shofu Porcelain Laminate Polishing Kit (SCer); (4) polishing with Brasseler Dialite Feather lite All- Ceramic Adjusting & Polishing System (BCer); (5) polishing with Shofu Composite Polishing Kit (SCom); and (6) polishing with Brasseler Composite Polishing Kit (BCom). The polished crown surface topography was observed, and surface roughness and area were measured with AFM. In addition, polished crowns were visually assessed by 15 senior dental students and 15 dental school faculty members. Results: All polishing treatments significantly reduced the surface roughness and area of the crown compared with the control. SCom and BCom showed significantly higher surface area than VEna, and the SCer and BCer groups were intermediate, showing no significant difference from either VEna or SCom and BCom. There were no significant differences in surface roughness between any of the systems. Dental students and faculty members classified the groups polished with VEna, SCer, and BCer groups as clinically acceptable, and they selected BCer group as the best polished restorations and the control group as the least polished restorations. Conclusions: Ceramic and composite polishing systems produced similar polishing results as that observed using a company proprietary polishing system. However, effectiveness for polishing using a company proprietary and ceramic polishing system tends to be higher than composite polishing systems.

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Retreatment of 6 Ceramic Restorations In A Single Session - The Application of Er:YAG Laser And CAD/CAM Technology: An 1 Year Follow Up Clinical Evaluation

Brazilian Dental Science ◽

10.14295/bds.2021.v24i2.2234 ◽

2021 ◽

Vol 24 (2) ◽

Author(s):

Christian Giancarlo Bernal ◽

Ester Mi Ryoung Lee ◽

Carlos De Paula Eduardo ◽

Ana Maria Aparecida Souza ◽

Luciane Hiramatsu Azevedo

Keyword(s):

High Speed ◽

Er:Yag Laser ◽

Single Session ◽

High Power Lasers ◽

Yag Laser ◽

Anesthetic Agents ◽

All Ceramic ◽

Cad Cam ◽

Ceramic Restorations

Background: To present the benefits of high power lasers (Er: YAG and Nd: YAG) over the use of the high speed turbine for the extraction of ceramics restorations, without damaging the surfaces of the teeth; being a relatively easier and faster procedure without the use of anesthetic agents, and the preparation of the ceramic restorations and cementing in the single session; with a follow-up of 1 year. Objective: The benefits of lasers over high-speed turbine mechanical instrumentation for crown removal encompass efficient restoration recovery without damage to tooth surfaces; and a relatively easier and faster procedure without the use of anesthetic agents. Methods: The Er: YAG laser (no contact; 3.2-4.0 W, 20 Hz) was used to extract the porcelain prosthesis, followed by a gingivectomy with the Nd: YAG laser on tooth 12 to improve the gingival contour. The dental surfaces where the ceramic prosthesis will be cemented were scanned. Then, CAD / CAM technology was used to make the ceramic veneers that were cemented in the same session. Results: The efficacy the Er:YAG laser energy was observed by the decreased of the time to remove all-ceramic materials through ablation of bonding cements, reducing working time by 75% compared to a high-speed turbine. Conclusions: An Er: YAG laser can safely remove lithium disilicate crowns with the settings used in this study. Laser-assisted removal of all ceramic PDFs is a promising treatment protocol. The use of the Nd: YAG (2.0 W power, short 20Hz, 320 µm optical fiber, in contact) laser allowed gingivoplasty to be performed, automatically cauterizing avoiding post-operative bleeding, and facilitating the preparation of ceramic restorations the same day. The use of high-power lasers and the use of accompanying CAD / CAM technology allowed this clinical case to be completed in a single visit without the use of temporary restorations, achieving absolute patient satisfaction. Keywords Er:YAG; Nd:YAG; Lithium disilicate ceramic; CAD/CAM.

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Technical and Biological Complications of Screw-Retained (CAD/CAM) Monolithic and Partial Veneer Zirconia for Fixed Dental Prostheses on Posterior Implants Using a Digital Workflow: A 3-Year Cross-Sectional Retrospective Study

BioMed Research International ◽

10.1155/2021/5581435 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Paolo De Angelis ◽

Giulio Gasparini ◽

Francesca Camodeca ◽

Silvio De Angelis ◽

Margherita Giorgia Liguori ◽

...

Keyword(s):

Survival Rate ◽

Cross Sectional ◽

Digital Workflow ◽

Fixed Dental Prosthesis ◽

Significant Difference ◽

Cad Cam ◽

Study Population ◽

Clinically Significant ◽

Technical Complication ◽

Ceramic Restorations

Objective. The introduction of CAD/CAM and the development of zirconia-based restorations have allowed clinicians to use less expensive materials and faster manufacturing procedures. The purpose of the study was to analyze the differences, in terms of mechanical and biological complication, in multiunit zirconia fixed dental prosthesis (FPDs) on posterior implants produced using a digital workflow. Method and Materials. This study was a retrospective investigation, and patients treated with screw-retained monolithic or partial veneer FPDs on dental implants were selected. Periapical radiographs were taken at baseline and at the 3-year follow-up. Complications were recorded and classified as technical and biological ones. Results. The study population included 25 patients. The occlusal and interproximal corrections were not clinically significant. In the study sample, the survival rate and success rate of the FPDs after 3 years were 100% and 96%, respectively. One implant failed immediately after placement. Conclusion. Monolithic zirconia FPDs and partial veneer FPDs showed a 100% survival rate, presenting an interesting alternative to metal ceramic restorations. The partial veneer FPDs had a higher technical complication rate than the monolithic FPDs; however, no statistically significant difference was found.

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Effect of the bur grit size on the flexural strength of a glass-ceramic

Cerâmica ◽

10.1590/0366-69132016623621988 ◽

2016 ◽

Vol 62 (362) ◽

pp. 121-127 ◽

Cited By ~ 1

Author(s):

P. P. Kist ◽

I. L. Aurélio ◽

M. Amaral ◽

L. G. May

Keyword(s):

Surface Roughness ◽

Flexural Strength ◽

Glass Ceramic ◽

Glass Ceramics ◽

Internal Surface ◽

Grit Size ◽

Diamond Grit ◽

Cad Cam ◽

Negative Effect ◽

Ceramic Blocks

Abstract The purpose of the present study was to determine the biaxial flexural strength (BFS) of a CAD/CAM leucite reinforced glass-ceramic ground by diamond burs of different grit sizes and the influence of surface roughness on the BFS. For this, 104 plates were obtained from CAD/CAM ceramic blocks and divided into 4 groups (n = 26), according to bur grit size: extra-fine, fine, medium and coarse. Roughness parameters (Ra, RyMax) were measured, and plates were kept dry for 7 days. The flexural test was carried out and BFS was calculated. Ra, RyMax and BFS data were subjected to analysis of variance and post-hoc test. Weibull analysis was used to compare characteristic strength and Weibull modulus. Regression analysis was performed for BFS vs. Ra and RyMax. When burs with coarse grit were used, higher surface roughness values were found, causing a negative effect on the ceramic BFS (117 MPa for extra-fine, and 83 MPa for coarse). Correlation (r) between surface roughness and BFS was 0.78 for RyMax and 0.73 for Ra. Increases in diamond grit size have a significant negative effect on the BFS of leucite-reinforced glass-ceramics, suggesting that grinding of sintered glass-ceramic should be performed using burs with the finest grit possible in order to minimize internal surface flaws and maximize flexural strength.

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