Except good hygiene can't prevent the teeth problems that arise from Bruxism. Xerostomia might be the most widespread problem causer and yes, to those that know better it's mostly preventable, but a brux mouthpiece is harder to talk someone into using till some moderate damage has been done. That and a good portion occurs in one's sleep after they're finally passed out. That was the problem my friend's older brother had and he spent a fortune having it fixed later in life, like a decade after he stopped, not just a couple years after, like in his 20's.
Saline nasal spray can help with the corrosiveness of snorting lines and somewhat mitigate any inflammation/ necrosis as the NaCl buffers it a little. Plain water not so much. If it burns when shooting then a pinch of NaHCO3 can help with vein sclerosis.
For smoking, which when done properly is actually vaping, try to avoid holding it in like pot smoke. It's better to smoke a little more then to wallpaper your alveoli & bronchial tubes. Water, Listerine as much as possible & Biotene for when you crash or don't have water. Brushing your teeth at midnight and noon is a good idea since your schedule won't involve much going to bed and waking up (normal brushing times). Lastly there's "plugging" which might come across as odd but another Mod who is on a break right now used to speak favorably of it, just be careful you don't do too much as it can hit pretty hard. Or you could rotate all three methods.
The water and Biotene can also help with Xerostomia (dry mouth) from cannabis if you like reg cokes and candy or just want to take extra good care of your oral hygiene. Hope it works out.