Fracture Strength of Implant-Supported Ceramic Crowns with Customized Zirconia Abutments: Screw Retained vs. Cement Retained

Metal ceramic restorations have been implicated for the discoloration in area of labiogingivalmargin. Attempts to rectify this, by altering the design of metal frameworkswill lead to decrease in fracture strength atmargin. This in vitro study compared the fracture strength at margins of metal ceramic crowns cemented to metal tooth analogs. Crowns evaluated with different marginal configurations, shoulder and shoulder bevel with 0 mm, 0.5 mm, 1 mm, and 1.5 mm, were selected.Methods. Maxillary right canine typhodont tooth was prepared to receive a metal ceramic crown with shoulder margin. This was duplicated to get 20 metal teeth analogs. Then the same tooth was reprepared to get shoulder bevel configuration. These crowns were then cemented onmetal teeth analogs and tested for fracture strength atmargin on an Instron testing machine. A progressive compressive load was applied using 6.3 mm diameter rod with crosshead speed of 2.5 mm per minute. Statisticaly analysis was performed with ANOVA, Student's “t” test and “f” test.Results. The fracture strength of collarless metal ceramic crowns under study exceeded the normal biting force. Therefore it can be suggested that collarless metal ceramic crowns with shoulder or shoulder bevel margins up to 1.5 mm framework reduction may be indicated for anteriormetal ceramic restorations.Significance. k Collarless metal ceramic crowns have proved to be successful for anterior fixed restorations. Hence, it may be subjected to more clinical trials.

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Fracture Strength of Zirconia and Alumina Ceramic Crowns Supported by Implants

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-13-00142 ◽

2015 ◽

Vol 41 (S1) ◽

pp. 352-359 ◽

Cited By ~ 3

Author(s):

Tonino Traini ◽

Roberto Sorrentino ◽

Enrico Gherlone ◽

Federico Perfetti ◽

Patrizio Bollero ◽

...

Keyword(s):

Fracture Strength ◽

Glass Ceramic ◽

Ceramic Materials ◽

Fracture Load ◽

Fractographic Analysis ◽

Core Material ◽

Loading Test ◽

Significant Difference ◽

Cad Cam ◽

Ceramic Crowns

Due to the brittleness and limited tensile strength of the veneering glass-ceramic materials, the methods that combine strong core material (as zirconia or alumina) are still under debate. The present study aims to evaluate the fracture strength and the mechanism of failure through fractographic analysis of single all-ceramic crowns supported by implants. Forty premolar cores were fabricated with CAD/CAM technology using alumina (n = 20) and zirconia (n = 20). The specimens were veneered with glass-ceramic, cemented on titanium abutments, and subjected to loading test until fracture. SEM fractographic analysis was also performed. The fracture load was 1165 (±509) N for alumina and 1638 (±662) N for zirconia with a statistically significant difference between the two groups (P = 0.026). Fractographic analysis of alumina-glass-ceramic crowns, showed the presence of catastrophic cracks through the entire thickness of the alumina core; for the zirconia-glass-ceramic crowns, the cracks involved mainly the thickness of the ceramic veneering layer. The sandblast procedure of the zirconia core influenced crack path deflection. Few samples (n = 3) showed limited microcracks of the zirconia core. Zirconia showed a significantly higher fracture strength value in implant-supported restorations, indicating the role played by the high resistant cores for premolar crowns.

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Effects of surface finish and fatigue testing on the fracture strength of CAD-CAM and pressed-ceramic crowns

Journal of Prosthetic Dentistry ◽

10.1016/s0022-3913(99)70036-3 ◽

1999 ◽

Vol 82 (4) ◽

pp. 468-475 ◽

Cited By ~ 73

Author(s):

Hong Yan Chen ◽

Reinhard Hickel ◽

James C Setcos ◽

Karl-Heinz Kunzelmann

Keyword(s):

Surface Finish ◽

Fracture Strength ◽

Fatigue Testing ◽

Cad Cam ◽

Ceramic Crowns

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Polymer-Based Bioactive Luting Agents for Cementation of All-Ceramic Crowns: An SEM, EDX, Microleakage, Fracture Strength, and Color Stability Study

Polymers ◽

10.3390/polym13234227 ◽

2021 ◽

Vol 13 (23) ◽

pp. 4227

Author(s):

Samer Al-Saleh ◽

Turki W. Aboghosh ◽

Mousa S. Hazazi ◽

Khalid A. Binsaeed ◽

Abdulaziz M. Almuhaisen ◽

...

Keyword(s):

Fracture Strength ◽

Color Change ◽

Testing Machine ◽

Color Stability ◽

Stability Study ◽

Resin Cement ◽

Resin Cements ◽

All Ceramic ◽

Ceramic Crowns ◽

Group 2

The aim of the study was to compare microleakage and fracture loads of all ceramic crowns luted with conventional polymer resins and polymeric bioactive cements and to assess the color stability of polymeric bioactive cements. Seventy-five extracted premolar teeth were tested for fracture loads and microleakage in all-ceramic crowns cemented with two types of polymeric bioactive cements and resin cements. In addition, the degree of color change for each cement with coffee was assessed. Thirty maxillary premolar teeth for fracture loads and thirty mandibular premolar teeth for microleakage were prepared; standardized teeth preparations were performed by a single experienced operator. All prepared specimens were randomly distributed to three groups (n = 20) based on the type of cement, Group 1: resin cement (Multilink N); Group 2: polymeric bioactive cement (ACTIVA); Group 3: polymeric bioactive cement (Ceramir). The cementation procedures for all cements (Multilink, ACTIVA, and Ceramir) were performed according to the manufacturers’ instructions. All specimens were aged using thermocycling for 30,000 cycles (5–55 °C, dwell time 30 s). These specimens were tested using the universal testing machine for fracture strength and with a micro-CT for microleakage. For the color stability evaluation, the cement specimens were immersed in coffee and evaluated with a spectrometer. Results: The highest and lowest means for fracture loads were observed in resin cements (49.5 ± 8.85) and Ceramir (39.8 ± 9.16), respectively. Ceramir (2.563 ± 0.71) showed the highest microleakage compared to resin (0.70 ± 0.75) and ACTIVA (0.61 ± 0.56). ACTIVA cements showed comparable fracture loads, microleakage, and stain resistance compared to resin cements.

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