Any that cover the teeth which are causing you problems.
This would probably do. I assume like a rugby guard, you put it in hot water and then mould it to your teeth. If it makes you gag a bit, but half a CM off the back of it, so it may not cover the wisdom teeth
As spath says, there are tooth guards on the internet which may well improve the situation for you, but my main concern in their use would be sleep apnoea.....snoring and stopping breathing....a particular concern if your are elderly and have cardiovascular disease.
My advice would be to either live with your problem, or see your dentists who would "smooth off" the offending tooth.
Spath “I see your issue similar to that of grinding the teeth” - precisely, so do I, although tooth-grinding per se isn’t my problem; it is lying on my left side!
I too try a sandboard to get rid of the sharp bits, but oddly, it’s hard to locate them - easy at 2 in the morning, though.