1 Plasma donors may donate as often as every 28 days. 2  Platelets donors may donate as frequently as every eight days, and up to 24 times in a 12-month period. 3  Double Red Cell donors maybe donate as often as every 168 days.
In some cases, perfectly straight teeth can become crooked with age, as the structure of your mouth changes, or due to tooth loss and movement of the remaining teeth. Teeth straightening can be achieved by a variety of different cosmetic dental techniques.
A dead tooth is a tooth that does not have a nerve inside it. The nerve has died. Normally teeth DO have a nerve inside them. It's what tells you if your coffee is hot or your ice cream is cold! I usually tell my patients that a tooth is a bit like a pencil. The nerve inside the tooth is like the pencil lead, running down the inside of the tooth.