Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Schematic diagram depicting common fracture modes in bilayer crowns: D shows contact damage, that may propagate causing delamination or chipping, R depicts radial cracks, which lead to bulk fracture or marginal fracture, and C shows edge chipping, originated in the cusp area.
