is it possible to replace carbide saw teeth yourself? How do you do it?

Answer 1

No, it takes special equipment to install them. They have to be very secure. I have seen it done & it isn't a job for an amateur.

Answer 2

A carbide tipped saw blade isn't worth the effort compared to the price of just buying a new one. I know miter saw blades can be sort of pricey but they are made for fine, finish work like trim, even if you managed to re-attach the teeth, it wouldn't be any good for fine cuts anymore. Missing teeth aren't as detrimental to a saw cut as an out of line sawtooth.
On the jobsite, we never throw out our old saw blades. We save them for demo work, anything that doesn't require a precise cut, like removing an asphalt shingle roof. Or cutting through things that may have nails in it. You don't want to use a new blade on things like that. You can also use an old sawblade for cutting aluminum and vinyl siding (just mount the saw blade backward on the saw). There are plenty of uses for an old saw blade. As far as repairing them, I've never seen anyone try, mainly because they are cheap enough to just replace.