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.
8 ]. Age: Glomerular filtration rate deÂ­clines with age. A rule of thumb is that the GFR stays within the normal range (~100 mL/min) until the age of 40, and then declines at approximately 10 mL/min per decade, so that at age 80, normal GFR is 60 mL/min. rule of thumb is that the GFR stays within the normal range (~100 mL/min) until the age of 40, and then declines at approximately 10 mL/min per decade, so that at age 80, normal GFR is 60 mL/min.