Rudolf Marx

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Ceramic materials are used as implants and prostheses because of their excellent biocompatibility and in the dental field beyond that, because of esthetic advantages and the little plaque accumulation. A disadvantage is their sensitivity to microscopic cracks because of their brittleness. Strength-deteriorating microscopic cracks can be introduced into the(More)
A large series of cranial bone grafts performed during a 6-year period is presented. The types of grafts are discussed and the techniques of taking the grafts are described. The complications have been few. Full-thickness skull penetration occasionally occurs but should not be a cause for concern. The skull has gradually become our main bone graft donor(More)
Dental bridges made of polymer materials reveal only low loading capacity. This paper analyzes possible improvements of the loading capacity of polymer-based dental bridges reinforced by incorporated ceramic bars. Finite element (FE) analyses were performed to study the stress distribution caused by the mastication process in the bridge material. In the(More)
Information processing (and cognitive ERPs as their concomitants) has been observed to be disturbed in chronic alcoholics and to recover with sustained abstinence. However, some specific components of ERPs appear to remain significantly decreased in long-term abstinent alcoholics. Using a longitudinal design we investigated the effect of abstinence and(More)
OBJECTIVES Prosthetic posts made of zirconia ceramics are beneficial because of their esthetic advantages. The mechanical reliability of ceramic posts is limited because of the strength level and the large scatter in strength of ceramic materials. The hypothesis of this study is that the failure of ceramic posts in vivo, which occur on low-quality posts(More)
OBJECTIVES The aim of this study was to compare two fracture toughness methods, the bending method on notched specimens as reference and the indentation method as comparison. Potentialities and limitations of the indentation method were analyzed. METHODS Fracture toughness values were determined for seven dental ceramic materials on 'single-edge-v-notched(More)
There has been limited use of ceramic materials for all-ceramic posterior bridges. Major reasons are the low strength, the strength scatter, and the time-dependent strength decrease of ceramics due to slow crack growth. The objective of this study was to predict the long-term failure probability and loading capability of all-ceramic bridges (Empress 1,(More)
STATEMENT OF PROBLEM Because of their specific mechanical properties, all-ceramic restorations demonstrate a lower fracture resistance than ceramic restorations supported by metal substructures. However, advances have been made in the fabrication of high-strength all-ceramic abutments for anterior implants. No previous study has compared the fracture loads(More)
The strength of ceramic restorations depends on the occlusal surface roughness of the veneering porcelain, which is influenced by the final preparation. The hypothesis of the study was that roughnesses below a critical microscopic defect size--based only on fracture mechanics considerations--also affect flexural strength. The bending failure stress was(More)