You should expect about 3 to five years (possibly 7 years) of use from the composite and as many as 20 years or longer from an amalgam restoration. Actually a well-cared-for amalgam filling can last a lifetime, so the expensiveness of the filling really becomes a minor consideration.
This shows how well the kidneys are performing. In a normal healthy person the GFR stays close to the same value all of the time. The test is done by taking blood from a person and sending it to a laboratory. Normal values are between 90ml/min and 110ml/min.
The process of filtration of the blood in the Bowman's capsule is ultrafiltration (or glomerular filtration), and the normal rate of filtration is 125 ml/min, equivalent to ten times the blood volume daily. Measuring the glomerular filtration rate (GFR) is a diagnostic test of kidney function.