A new dimensionless relationship for analysis of ballistic penetration data is derived and applied to polycrystalline ceramic materials. Targets consist of ceramic tiles backed by thick metallic plates within which residual penetration depths have been reported in experimental studies. Particular ceramics analyzed here are lowand high-purity alumina, aluminum nitride, boron carbide, silicon car...

The use of bi-layered all-ceramic crowns has continuously grown since the introduction of computer-aided design/computer-aided manufacturing (CAD/CAM) zirconia cores. Unfortunately, despite the outstanding mechanical properties of zirconia, problems related to porcelain cracking or chipping remain. One of the reasons for this is that ceramic copings are usually milled to uniform thicknesses of ...

The treatment of severe tetracycline discoloration is a challenge for the dentist. There are several treatment options and one of the most effective is the use of feldspathic veneers. The aim of this clinical case was to carry out the replacement with conventional feldspathic ceramic veneers on a patient with highly stained teeth (grade IV tetracycline) by a minimally invasive approach. Clinica...

The 3D moldability of veneers, as opposed to the moldability of plastic or other materials, is limited because of the characteristics of wood. By mechanical treatment under appropriate conditions, it is possible to partially modify veneer characteristics. In this study, the intention was to determine the effect of factors influencing the 3D moldability of veneers. Therefore, this study was focu...

The purpose of this study was to investigate how water aging of the resin cement influences the stress distribution in all-ceramic crowns and if there is an increase in the propensity for crown failure. The failure of all-ceramic crowns attributed to cement degradation was explored using a combination of experimental and numerical methods. Sectioned all-ceramic crown specimens were fabricated o...

PURPOSE This study examined the influence of ceramic coping thickness on the maximum stresses that arise in a first premolar all-ceramic crown. MATERIALS AND METHODS Axisymmetric finite element models with different In-Ceram Alumina coping thicknesses (0.3, 0.6, and 0.9 mm) were examined. Models with and without resin lute were constructed. To all models, an identical axial load of 600 N was ...

The 1-piece, implant-supported abutment and crown, colloquially described as the UCLA abutment, commonly is used to fabricate single, screw-retained crowns. This abutment was designed to allow attachment of the crown directly to the implant and requires a waxing and casting procedure by a laboratory technician. A new prefabricated abutment has been developed that uses a similar approach but doe...

Orthodontic extrusion is usually performed by means of a fixed orthodontic appliance that utilizes arch wire attached to adjacent teeth and transfers the desired force by elastic from the wire to the root. However, clinicians often encounter cases where the bonding required for tooth traction is not possible because the adjacent teeth have been restored with ceramic or veneer. The purpose of th...

The aim of this in vitro study was to evaluate the influence of endodontic therapy, veneer preparation, and their association on fracture resistance and deflection of pulpless anterior teeth and assess whether restoration with quartz fiber-reinforced post can influence these properties. Seventy-five freshly extracted human maxillary central incisors were selected. Teeth were randomly divided in...