Cocaine can be detected in the system anywhere from 12 hours to 4 days after use. The length of time cocaine stays in your system depends on the dosage amount ingested, the route of administration and frequency of use. When cocaine is metabolized, the liver turns it into benzoylecgonine, which is then excreted in urine.
BUT, if you chew gum a lot, especially if you have a lot of tension in the muscles of mastication anyways, you're going to have problems... The muscles that make the motion/act of chewing/clenching include the masseter, lateral/medial pterygoids, and the temporalis.
This exercise helps to fully stretch your masticatory muscles, the muscles in your jaw responsible for chewing and grinding. Massage your jaw muscles with your fingertips using small, circular motions. Now open your mouth as wide as you can without pain or discomfort. Hold the stretch for 10 seconds, then release and relax your jaw.