Fracture strength of In-Ceram all-ceramic bridges in relation to cervical shape and try-in procedure. An in-vitro study.

Investigations were performed on the strength of dental porcelain depending on whether it was exposed to saliva before or after the final firing. Forty porcelain specimens were fabricated and subjected to different treatments. A three-point flexural test was performed. In a second study investigations were performed to compare how the cervical shape of the preparation influenced the fracture strength of fixed partial dentures made of glass-infiltrated aluminium oxide. It was concluded that short-term exposure to saliva could have a negative effect on the strength of porcelain and that all-ceramic bridges luted with non-adhesive luting techniques should be supported by abutments with shoulder preparations.