How much anesthetic is in a carpule?

Seems like an easy question right?
The glass carpule or cartridge is designed for 2cc of liquid local anesthetic right?
Makes all the calculations easy right?
WRONG!
First off, nobody thought of the rubber stopper when the glass cartridge was designed, and nobody ever bothered to change it. The rubber stopper takes up .2cc of volume, so there is 1.8cc available for the medication, right?
WELL MAYBE...
We all assumed for years that there was 1.8 cc of local anesthetic in each carpule. Then along comes articaine, which is finally ready to take on the FDA for use in the United States.
Nobody could prove that the carpule consistantly had 1.8cc of medication, once under the scrutiny of the FDA. They could prove there was 1.7cc all the time, but not always 1.8cc.
Articaine got labeled "1.7cc" or "at least 1.7cc" depending on the company you buy it from. Go ahead and check it out. Other companies soon followed for packaging of lidocaine and carbocaine.
What does this mean to us?
The change in numbers is very small, and if we practice safely, dosing patients really does not change, but the numbers are ridiculous!
Why didnt anyone ever remember the rubber stopper? Things would have been so much easier!
Except that we would then have to buy bigger syringes....