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.
a Reconstructed 3D image of a tooth. b Perpendicular cross-sections of a root and an obturated root canal: background (black), dentine (dark grey) and filling material (white). Voids in the filling material are seen in 2D cross-sections as clusters of dark pixels surrounded by bright pixels.
