HOME - Clinical cases - Digital Dentistry
 
 
20 November 2019

Resistance to the cyclic fatigue of two CAD/CAM ceramic materials: preliminary analysis on simulators

Massimo Gagliani


Premolars are the most difficult elements to restore and have a high failure rate due to their anatomical position and the forces they undergo. 
Therefore the choice of the material to restore these elements must be well thought out. With the introduction of the CAD / CAM system, different materials are available with the aim of ensuring resistance and aesthetics to the teeth. Among these we find lithium disilicate (LD) and ceramic infiltrated polymer (PICN). 
But which of these two guarantees a better resistance to cyclic fatigue?
Homaei et al in their study try to answer to this question and they investigated the resistance to cyclic fatigue of restored premolars with these two different types of dental CAD/CAM ceramics.

Materials and Methods
A restored premolar with a full coverage crown has been digitized. The volumetric shape of the teeth and crown tissues has been recreated in Mimics®. They were transferred to IA-FEMesh for mesh generation and the model was analyzed with Abaqus. Through these software combinations it was possible to simulate a clinical situation to assess the distribution of stress on the restorations themselves, subsequently it was possible to hypothesize the duration of the premolars restored with the two different materials

Results
The expected duration was 1,231,318 cycles for LD with a fatigue load of 1,400 N, while that for PIC was 475,063 cycles with a load of 870 N. The peak value of the maximum principal stress occurred in the occlusal contact areas ( antagonist) (LD: 172 MPa and PIC: 96 MPa) and in the central fossa (LD: 100 MPa and PIC: 64 MPa) and for both ceramics these were the areas of failure most often seen in the experiment. As far as the adhesive layer was concerned, the maximum shear stress was observed in the shoulder area (LD: 53.6 MPa and PIC: 29 MPa).

Conclusion 
The resistance to cyclic fatigue and the failure modes of the ceramic crowns are better in lithium disilicate group than PICN ones. So, for what concern premolars restorations, it's better to choose LD than PICN.


For additional informations: Numerical fatigue analysis of premolars restored by CAD/CAM ceramic crowns


Related articles

Inlay and overlay are a good and right choice in case of large carious and restorative defects. The introduction of CAD/CAM system gives the possibilities to...


Contemporary computer-aided design and manufacturing (CAD/CAM) systems involve a wide range of dental restoration indications such as inlays, onlays, laminate...


With the development of CAD/CAM system, nowadays the most used materials in the prosthetic fields are: zirconia and lithium disilicate. In particular, in a...


The increased aesthetic demand, without sacrificing the preservation of biological structures, has led to the development and use, in recent years, new generations...


Author: Rafi Romano

The following clinical case presents complex aesthetic and functional case of sever deep bite with relapse of previous orthodontic treatment in childhood, combined...


Read more

USA     20 February 2020 - 22 February 2020

Midwinter Meeting 2020

Where: McCormick Place West Building, 2301 S. Indiana Ave., ChicagoWhen: on February 20-22, 2020Topic: Restorative dentistry, Oral Cancer Symposium, Implantology, Health and Wellness, The business...


Dentists must regularly determine the best adhesive cementation protocol for glass-ceramic restorations on posterior teeth. A few in vivo follow-up...


Peri-implant mucositis is an inflammation of the mucosa around dental implant. Clinically, it is characterized by mucosal bleeding on peri-implant ...


Intrabony cista in the jaw are the most common benign findings in the oral and maxillofacial area. The best treatment option to manage intrabony cystic lesions...


Clinical management of periodontally compromised teeth with advanced mobility remains an arduous challenge to the dentists. Splints are being used to overcome...


 
 
 
 

Newsletter

 
 
 
 

Most popular

 
 

Events