Yesterday I 'formed' two new night guards and when I bit into a hard cracker later that night, I noticed one of my teeth felt 'sore' or 'bruised'. It's number 28 on the chart. No pain or discomfort otherwise and today the discomfort is minimal. My teeth did sort of stick to the hot plastic (the heat did not hurt) so I'm wondering if this is something I should worry about. I've tapped it with a pen and feel nothing. Only the bruised feel when I bite something very hard and a teeny sensation if I attempt to wiggle it. I'm 62 and not due to see my dentist for a few months.