Biomedical subjects

H W Wiskott

Publications and source records attributed to H W Wiskott.

21 records · Page 2Linked to original sources

PubMedDate not supplied

Stress fatigue: basic principles and prosthodontic implications.

Clinical evidence indicates that the majority of fractures that occur in prosthodontic structures do so after a period of many years. Such failures generally are not related to an episode of acute overload but result from fatigue failure. This paper reviews the current knowledge of fatigue failure and test methods. An overview of published studies is given, and the authors suggest guidelines for future prosthodontic studies of this nature.

Chemical Phenomena↗

PubMedDate not supplied

The relationship between abutment taper and resistance of cemented crowns to dynamic loading.

This study investigated the relationship between abutment total occlusal convergence angle (taper) and the resistance of cemented crowns subjected to dynamic loading. Crown and abutment analogs were placed using zinc-oxide-eugenol, zinc-phosphate, glass-ionomer, or resin composite cement. Total occlusal convergence angles of 2.5, 5, 10, 15, 20, 30, and 40 degrees were used. Dynamic stresses were applied to the luted components until the bond failed or the components reached 10(6) load cycles. The data were analyzed using the staircase technique. The relationship between convergence and resistance was approximately linear for all the cements tested. Crowns luted with resin composite cement were more resistant to dynamic lateral loading than those placed using glass-ionomer or zinc-phosphate cements. Crowns luted with zinc-oxide-eugenol cement presented the least resistance to cyclic lateral stresses.

Cementation↗

PubMedDate not supplied

The effect of tooth preparation height and diameter on the resistance of complete crowns to fatigue loading.

This study investigated the relationship between tooth preparation height and diameter and the resistance of cemented crowns to dynamic loading. Crown and abutment analogs were cemented using zinc oxide-eugenol, zinc phosphate, glass-ionomer, and resin composite luting agents. Abutment height varied from 1 to 7 mm in increments of 1 mm. Diameters of 3, 4, 5, 6, 7, and 8 mm were tested. A testing apparatus designed to apply dynamic stresses was used. The cemented crowns were loaded until the cement bond failed or the components reached 1 million stress cycles. The staircase technique was applied for data analysis. The results showed that: (1) the relationship between abutment height (or diameter) and resistance to dynamic lateral loading is approximately linear; and (2) crowns luted using resin composite cement were more resistant than those placed using glass-ionomer cement, which in turn were more resistant than crowns cemented with zinc phosphate or zinc oxide-eugenol cements.

Cementation↗