The Procera crown â Procera is a milled ceramic on the inside with a more traditional porcelain baked onto the outside. The advantage of Procera is its exceptional strength. However, the milled ceramic core is opaque white, so many cosmetic dentists feel that it isnât as natural-looking as the more translucent materials.
1 February: On February 15 the Romans celebrated the festival of forgiveness for sins; (februare, Latin to purify), 2  March: Mars, the Roman god of war,  April: Roman month Aprilis, perhaps derived from aperire, (Latin to open, as in opening buds and blossoms) or perhaps from Aphrodite, original Greek name of Venus,
Origin of the names of the days. The names of the days are in some cases derived from Teutonic deities or, such as in Romance languages, from Roman deities. The early Romans, around the first century, used Saturday as the first day of the week. As the worshipping of the Sun increased, the Sun's day (Sunday) advanced from position of the second day to the first day of the week (and saturday became the seventh day).