Ceramic fracture in metal-ceramic restorations: the aetiology

Dental Update ◽  
2017 ◽  
Vol 44 (5) ◽  
pp. 448-456
Author(s):  
Ayesha Aslam ◽  
Danish Azeem Khan ◽  
Syed Hammad Hassan ◽  
Bilal Ahmed
2021 ◽  
Vol 11 (7) ◽  
pp. 2988
Author(s):  
Celia Tobar ◽  
Verónica Rodríguez ◽  
Carlos Lopez-Suarez ◽  
Jesús Peláez ◽  
Jorge Cortés-Bretón Brinckmann ◽  
...  

The introduction of new digital technologies represents an important advance to fabricate metal–ceramic restorations. However, few studies have evaluated the influence of these technologies on the fit of the restorations. The aim of this study was to evaluate the effect of different manufacturing techniques and pontic design on the vertical marginal fit of cobalt–-chromium (Co–Cr) posterior fixed partial dentures (FPDs) frameworks. Methods: Eighty stainless-steel dies were prepared to receive 3-unit FPDs frameworks with intermediate pontic (n = 40) and cantilever pontic (n = 40). Within each design, the specimens were randomly divided into four groups (n = 10 each) depending on the manufacturing technique: casting (CM), direct metal laser sintering (LS), soft metal milling (SM), and hard metal milling (HM). The frameworks were luted, and the vertical marginal discrepancy was assessed. Data analysis was made using Kruskal–Wallis and Mann–Whitney U tests (α = 0.05). Results: The vertical marginal discrepancy values of all FPDs were below 50 μm. The HM frameworks obtained the lowest misfit values in both designs. However, no differences were found among intermediate pontic groups or cantilevered groups. Likewise, when differences in a marginal discrepancy between both framework designs were analyzed, no differences were observed. Conclusions: The analyzed digital technologies demonstrated high precision of fit on Co–Cr frameworks and on both pontic designs.


2019 ◽  
Vol 3 (1) ◽  
pp. 22
Author(s):  
Galih Paramarta ◽  
Eny Inayati

Background: The low levels of patient satisfaction and confidence in the restoration of the gingival resorption results in impaired quality of life in both functional and psychosocial aspects. It is necessary to manufacture a dental restoration to restore the mastication, phonetic, and aesthetic functions associated with soft tissue repair. Manufacture of gingiva ceramic restorations which are believed to be an alternative to restore the aesthetic function and harmonization of the patient’s teeth. In terms of manufacturing techniques, this restoration has a level of difficulty in achieving a balance between “White aesthetic” and “aesthetic pink”. Objective: This study aims to provide knowledge to the reader of Manufacturing Technique of Metal Ceramic Restoration with Implant-Abutment at Gingival Resorption Case. Reviews: Gingiva ceramic restorations can be used to create esthetic implant-supported restorations when bone and gingival tissues are deficient and surgical replacement of such tissues is not possible. Dental technicians should be able to analyze the three-dimensional shapes of gingival anatomy, color, texture, smile components, the balance of the “pink aesthetic” and “white aesthetic”. Conclusion: Manufacturing Technique of Metal Ceramic Restoration with Implant-Abutment at Gingival Resorption Case including the manufacture of metal coping, oxidation, application of opaque coating, application of the first “white aesthetic” ceramics (Opaque Dentine, Dentine, Enamel and transpa on crown coping restorations), Application of opaque gingiva layer, gingival ceramics build-up "pink aesthetics”, first firing, followed by correction build-up, and second firing, and ends with the glazing process.


2008 ◽  
Vol 02 (01) ◽  
pp. 63-68
Author(s):  
Süha Turkaslan ◽  
Arzu Tezvergil-Mutluay

ABSTRACTAll ceramic fixed partial dentures (FPD)s exhibit enhanced biocompatibility and esthetics as compared to metal-ceramic restorations. However, framework fractures are frequently reported especially when the connector dimensions are inadequate to withstand the high tensile stresses. The repair of the failed connector would be desirable rather than the complete removal and renewal since the latter is an expensive and time consuming procedure. Furthermore, the replacement or removal of the restoration for extra-oral repair purposes might increase the risk of destroying the entire restoration or damaging the abutment teeth during the removal. This article presents a direct intra-oral method that may be used to repair the connector fractures of all-ceramic FPDs which are otherwise clinically satisfactory. In the present technique, the connector is reconstructed intraorally utilizing composite resin restorative material reinforced with E-glass-fiber. (Eur J Dent 2008;2:63-68)


2018 ◽  
Vol 876 ◽  
pp. 25-30
Author(s):  
Liliana Porojan ◽  
Mihaela Bîrdeanu ◽  
Cristina Savencu ◽  
Sorin Porojan

It is known that the quality of metal-ceramic restorations mainly depends on the interface strength. The aim of the study was to evaluate metal–ceramic interfaces of heat pressed ceramic on Co-Cr frameworks obtained with different technologies: melting-casting (CST), computerized milling (MIL), selective laser sintering (SLS) and selective laser melting (SLM). The microstructure of metal–ceramic interfaces and framework topography were characterized by scanning electron microscope (SEM). Sandblasted, polished surfaces and the cross section on the interfaces were observed. Sandblasted surfaces presented a uniform rough aspect and pronounced porous surface compared to that of polished surfaces and were better visible in SLS and SLM samples. The thickness of the veneer layer had a noticeable effect on the interface, because in the case of thicker veneers, cracks at the interfaces were visible for CST and MIL specimens. Considering the findings reported herein, some suggestions can be considered in practice, such as adaptation of the restorations morphology to the characteristics of the processed materials.


Sign in / Sign up

Export Citation Format

Share Document