How long could you allow an abcessed tooth to go untreated before it infects the vital organs of the body? how long before systemic shock would occur?

Many variables: Firstly, you shouldn't allow an abscessed tooth to go untreated... It will only break down further and possibly become unrestorable. In the end you will still need to see a dentist for treatment. Factors such as the virulence of the bacteria and your immune system (resistance) play a role in the spread to other parts of your body. Call for and appointment asap.

Do not wait: It is of the upmost importance that a dental abcess be treated as soon as possible. The infection can spread outside of the mouth and can cause death if not teated.

Infected vs Affected: There is a difference b/t an "affected" organ and an "infected" organ. The affects of a abscessed tooth to end-organs happen much more quickly and can cause a host of other issues for the patient. Bottom line: do not wait, get any/all infections of the body resolved asap.

Russian Roulette: The infection is already spreading via your blood stream to all the other organs in your body. How quickly, how seriously, depends on your body...no two people are alike. The longer you wait, the greater the damage to the tooth and to the rest of your body. Please, you need immediate treatment.