Research on Dental Ceramic Grinding: A Review

2016 ◽  
Vol 693 ◽  
pp. 1106-1113
Author(s):  
Dan Na Zhao ◽  
Cheng Yong Wang ◽  
Xue Li Mao
Keyword(s):  
Cutting Tools ◽  
Surface Characteristics ◽  
Complex Surface ◽  
Ceramic Materials ◽  
Permanent Tooth ◽  
Grinding Force ◽  
Grinding Temperature ◽  
Dental Ceramics ◽  
Dental Ceramic ◽  
Ceramic Grinding

Dental ceramics has become dominant materials used in dental restorations. Dental ceramics have several advantages, such as stable performance, good bio-compatibility, little possibility to attach plaque, and similarity to the color of permanent tooth. However complex surface characteristics and hard and brittle properties of dental ceramic materials caused difficulties in the processing and subsequent grinding. The complicated craft and high failure rate of dental ceramics greatly limit its wide application in clinical. Thus, fully understanding the special cutting tools grinding performance and researching the material damage process caused by grinding temperature and grinding force are of great significance. Research on dental ceramic grinding was reviewed in this paper. The removal mechanism of dental ceramic materials and the influence of parameters settings on the grinding force, grinding temperature, and the surface quality have been studied. Besides the existing problems in dental ceramic grinding technology were pointed out.

scholarly journals Surface Characteristics and Biofilm Development on Selected Dental Ceramic Materials

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Kyoung H. Kim ◽  
Carolina Loch ◽  
J. Neil Waddell ◽  
Geoffrey Tompkins ◽  
Donald Schwass
Keyword(s):  
Surface Roughness ◽  
Surface Characteristics ◽  
Ceramic Materials ◽  
Irregular Surface ◽  
Dental Ceramics ◽  
Sem Images ◽  
Biofilm Growth ◽  
Crystal Violet Assay ◽  
Sem Imaging ◽  
Biofilm Development

Background. Intraoral adjustment and polishing of dental ceramics often affect their surface characteristics, promoting increased roughness and consequent biofilm growth. This study correlated surface roughness to biofilm development with four commercially available ceramic materials.Methods. Four ceramic materials (Vita Enamic®, Lava™ Ultimate, Vitablocs Mark II, and Wieland Reflex®) were prepared as per manufacturer instructions. Seventeen specimens of each material were adjusted and polished to simulate clinical intraoral procedures and another seventeen remained unaltered. Specimens were analysed by SEM imaging, confocal microscopy, and crystal violet assay.Results. SEM images showed more irregular surface topography in adjusted specimens than their respective controls. Surface roughness(Ra)values were greater in all materials following adjustments. All adjusted materials with the exception of Vitablocs Mark II promoted significantly greater biofilm growth relative to controls.Conclusion. Simulated intraoral polishing methods resulted in greater surface roughness and increased biofilm accumulation.

A New Method for Evaluating Thermal Compatibility of Multi-Layer Dental Ceramic Composites

2007 ◽  
Vol 330-332 ◽  
pp. 1401-1404
Author(s):  
Jun Cui ◽  
Jun Ou ◽  
Yong Lie Chao ◽  
Q.P. Gao ◽  
Guang Fu Yin ◽  
...  
Keyword(s):  
Thermal Shock ◽  
Ceramic Materials ◽  
Ceramic Composites ◽  
New Method ◽  
Stepwise Multiple Regression ◽  
Thermal Shock Test ◽  
Dental Ceramics ◽  
Thermal Mismatch ◽  
Dental Ceramic ◽  
Thermal Compatibility

Dental ceramic materials do not always show linear expansion behavior. In general, thermal contraction behavior of dental porcelain can be described with the polynomial function: L/L= C+α1 T+α2 T2. In addition, a new method for taking into consideration of nonlinear contraction behavior of dental ceramics is proposed for calculating thermal mismatch value (α) between substrate and veneering materials. Discs of eight substrate/veneer combinations (n=10) were fabricated for thermal shock testing. In this study, a stepwise multiple regression analysis was performed to determine the relationship between thermal shock test results and thermal mismatch value (α) on these combinations. A high degree of correlation was found between αs-b and T. The new method proves to be a reliable one to predict thermal compatibility of multi-layer dental ceramic composites.

Performance of Brazed Diamond Tool for Machining Dental Ceramic

2014 ◽  
Vol 1027 ◽  
pp. 84-87 ◽  
Author(s):  
Feng Lin Zhang ◽  
Yu Mei Zhou ◽  
Chang Wen Guo ◽  
Jun Bo Mao ◽  
Hui Ping Huang
Keyword(s):  
Diamond Tool ◽  
Process Capability ◽  
Grinding Force ◽  
Dental Ceramics ◽  
Dental Ceramic ◽  
Diamond Tools ◽  
Grinding Ratio ◽  
Electroplated Tool

Diamond tools are fabricated by brazing and used to machine dental ceramics in this paper. The morphology, grinding ratio, wear and grinding force of the brazed tools are investigated in comparison with that of the electroplated ones. The results show that the brazed alloy forms a hill-like structure around the diamond grits, and the protrusion of the brazed diamond grits is higher than that of the electroplated one. The grinding ratio of the brazed diamond tool is higher than the electroplated one. Many fall-off diamond pits of the electroplated tool and only few micro-crack diamond grits of the brazed tool are observed after grinding, and the brazed one remains well process capability. The grinding force of the electroplated tool is larger than that of the brazed one.

scholarly journals Study on the Effect of Grinding Pressure on Material Removal Behavior Performed on a Self-Designed Passive Grinding Simulator

2021 ◽  
Vol 11 (9) ◽  
pp. 4128
Author(s):  
Peng-Zhan Liu ◽  
Wen-Jun Zou ◽  
Jin Peng ◽  
Xu-Dong Song ◽  
Fu-Ren Xiao
Keyword(s):  
Residual Stress ◽  
Surface Roughness ◽  
Service Life ◽  
Material Removal ◽  
Removal Rate ◽  
Grinding Force ◽  
Grinding Wheel ◽  
Grinding Process ◽  
Grinding Temperature ◽  
Grinding Efficiency

Passive grinding is a new rail grinding strategy. In this work, the influence of grinding pressure on the removal behaviors of rail material in passive grinding was investigated by using a self-designed passive grinding simulator. Meanwhile, the surface morphology of the rail and grinding wheel were observed, and the grinding force and temperature were measured during the experiment. Results show that the increase of grinding pressure leads to the rise of rail removal rate, i.e., grinding efficiency, surface roughness, residual stress, grinding force and grinding temperature. Inversely, the enhancement of grinding pressure and grinding force will reduce the grinding ratio, which indicates that service life of grinding wheel decreases. The debris presents dissimilar morphology under different grinding pressure, which reflects the distinction in grinding process. Therefore, for rail passive grinding, the appropriate grinding pressure should be selected to balance the grinding quality and the use of grinding wheel.

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

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.

Forecasting Performance of Ceramic Cutting Tool

2017 ◽  
Vol 736 ◽  
pp. 86-90 ◽  
Author(s):  
Vyacheslav Maksarov ◽  
A. Khalimonenko
Keyword(s):  
Electrical Resistance ◽  
Cutting Tool ◽  
Cutting Tools ◽  
Tool Material ◽  
Ceramic Materials ◽  
Specific Electrical Resistance ◽  
Testing Methods ◽  
Microstructural Parameters ◽  
Forecasting Performance ◽  
Nondestructive Testing Methods

The article considers the problems of forecasting the performance of cutting tools equipped with replaceable ceramic cutting bits. It is proposed to forecast the operability of ceramic tools on the ground of dependence between its performance characteristics and the microstructural parameters of the tool material. It is proposed to determine the parameters of ceramic bits microstructure by a nondestructive testing methods based on measuring the specific electrical resistance of ceramic materials. As a result of the study we have undertaken, a relationship was detected between the performance and specific electrical resistance of ceramic cutting tools.

A fogászati kerámiaanyagok fejlődésének történeti áttekintése

2021 ◽  
Vol 11 (22) ◽  
pp. 284-293
Author(s):  
József Saláta
Keyword(s):  
Thermal Expansion ◽  
18Th Century ◽  
Ceramic Materials ◽  
Dental Ceramics ◽  
New Techniques ◽  
Casting Alloys ◽  
Burnt Clay ◽  
Cad Cam ◽  
Increasing Demand ◽  
Dental Casting Alloys

Initially, ceramics - mostly burnt clay - were used to manufacture container pottery. The first porcelain objects reached Europe out of China in the Medieval Ages. The technique of their manufacturing was a mystery for many hundred years, yet Germans succeeded first to produce fine European porcelain at the beginning of the 18th century. Its elegance and hardness woke the dentists’ interest too thus Frenchmen created the first porcelain dentures in the second half of the 18th century. Since then, there has been an increasing demand for esthetic fixed implant dentures instead of removable ones. The development of ceramic materials resulted in better mechanical and optical properties, thus the first fixed porcelain inlays and jacket crowns were introduced already in 1889. The addition of leucite filler crystals to porcelain in the 20th century increased the thermal expansion of the ceramic. It could be fired on common dental casting alloys, so the first porcelain-fused-to-metal (PFM) crown was created in 1962. Several new techniques were developed from the middle of the 1980s to the end of the 1990s to deal with initial shrinkage and achieve better properties. Beyond casting, pressing, and CAD/CAM technology, additive manufacturing opened new perspectives in dentistry several years ago in processing dental ceramics.

Experimental Evaluation on the Effect of Nanofluids Physical Properties With Different Concentrations on Grinding Temperature

2020 ◽  
pp. 203-225
Keyword(s):  
Heat Transfer ◽  
Base Fluid ◽  
Experimental Studies ◽  
Grinding Force ◽  
Grinding Temperature ◽  
Low Carbon ◽  
Heat Transfer Mechanism ◽  
Transfer Capability ◽  
Heat Transfer Capability ◽  
Technical Guidance

This chapter is proposed to solve the insufficient MQL cooling and heat transfer capability based on the heat transfer enhancement theory of solid. Adding nanoparticles into the base fluid can significantly elevate heat conductivity coefficient of the base fluid and enhance convective heat transfer capability of the grinding area. Researchers have carried out numerous experimental studies on nanofluids with different concentrations. However, the scientific nature of MQL cooling has not been explained. Degradable, nontoxic, low-carbon, and environmentally friendly green grinding fluid, palm oil taken as the base fluid, grinding force, grinding temperature and proportionality coefficient of energy transferred to workpiece of nanofluids with different volume fractions, are investigated in this chapter. Based on the analysis of the influence of physical characteristics of nanofluids on experimental results, cooling and heat transfer mechanism of NMQL grinding is studied. The experimental study can provide a certain technical guidance for industrial machining.

scholarly journals Validation and Comparison of MODIS C6.1 and C6 Aerosol Products over Beijing, China

2018 ◽  
Vol 10 (12) ◽  
pp. 2021 ◽  
Author(s):  
Xinpeng Tian ◽  
Qiang Liu ◽  
Xiuhong Li ◽  
Jing Wei
Keyword(s):  
Optical Properties ◽  
Urban Areas ◽  
Surface Characteristics ◽  
Complex Surface ◽  
Deep Blue ◽  
Spatial Coverage ◽  
Moderate Resolution ◽  
Moderate Resolution Imaging Spectroradiometer ◽  
Beijing China ◽  
Better Than

The operational Moderate Resolution Imaging Spectroradiometer (MODIS) Aerosol Products (APs) have provided long-term and wide-spatial-coverage aerosol optical properties across the globe, such as aerosol optical depth (AOD). However, the performance of the latest Collection 6.1 (C6.1) of MODIS APs is still unclear over urban areas that feature complex surface characteristics and aerosol models. The aim of this study was to validate and compare the performance of the MODIS C6.1 and C6 APs (MxD04, x = O for Terra, x = Y for Aqua) over Beijing, China. The results of the Dark Target (DT) and Deep Blue (DB) algorithms were validated against Aerosol Robotic Network (AERONET) ground-based observations at local sites. The retrieval uncertainties and accuracies were evaluated using the expected error (EE: ±0.05 + 15%) and the root-mean-square error (RMSE). It was found that the MODIS C6.1 DT products performed better than the C6 DT products, with a greater percentage (by about 13%–14%) of the retrievals falling within the EE. However, the DT retrievals collected from two collections were significantly overestimated in the Beijing region, with more than 64% and 48% of the samples falling above the EE for the Terra and Aqua satellites, respectively. The MODIS C6.1 DB products performed similarly to the C6 DB products, with 70%–73% of the retrievals matching within the EE and estimation uncertainties. Moreover, the DB algorithm performed much better than DT algorithm over urban areas, especially in winter where abundant missing pixels were found in DT products. To investigate the effects of factors on AOD retrievals, the variability in the assumed surface reflectance and the main optical properties applied in DT and DB algorithms are also analyzed.

scholarly journals Wear Characteristics of Dental Ceramic CAD/CAM Materials Opposing Various Dental Composite Resins

Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1839 ◽  
Author(s):  
Bora Gwon ◽  
Eun-Bin Bae ◽  
Jin-Ju Lee ◽  
Won-Tak Cho ◽  
Hyun-Young Bae ◽  
...  
Keyword(s):  
Weight Loss ◽  
Composite Resin ◽  
Lithium Disilicate ◽  
Composite Resins ◽  
Dental Composite ◽  
Dental Ceramics ◽  
Wear Properties ◽  
Dental Ceramic ◽  
Dental Composite Resins ◽  
Cad Cam

The aim of this study was to evaluate the wear properties of opposed dental ceramic restorative CAD/CAM materials and several posterior direct restorative composite resins. Three kinds of dental ceramics CAD/CAM materials (monolithic zirconia, lithium disilicate, leucite) and four dental composite resins—that is, MI Gracefil, Gradia Direct P, Estelite Σ Quick, and Filtek Supreme Ultra—were used in this study. For each of the 12 groups (three ceramics × four composite resins), five each of a canine-shaped ceramic specimen and a cuboidal shape opposing composite resin were prepared. All of the specimens were tested in a thermomechanical loading machine (50 N, 100,000 cycles, 5/55 °C). Wear losses of ceramic specimens and composite resin specimens were evaluated using a three-dimensional profiling system and an electronic scale, respectively. Statistical analyses were performed using the Kruskal–Wallis test and Mann–Whitney U test with Bonferroni’s correction. Zirconia showed significantly less volumetric loss than lithium disilicate or leucite regardless of composite resin type (p > 0.05/3 = 0.017), and that Estelite Σ Quick showed significantly more weight loss than Filtek Supreme Ultra, MI Gracefil, or Gradia Direct P regardless of ceramic type (p > 0.05/6 = 0.083). Zirconia showed less volumetric loss than lithium disilicate or leucite. Some composite resins opposing ceramics showed considerable weight loss.

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