Do we need separate categories for special types of humor?

A couple of old guys were golfing when one mentioned that he was going to go to Dr. Steinberg for a new set of dentures in the morning.

His elderly buddy remarked that he, too, had gone to the very same dentist two years before.

"Is that so?" asked the first old guy. "Did he do a good job?"

The second oldster replied, "Well, I was on the golf course yesterday
when a guy on the next fairway hooked a shot. The ball must have been going
at least 180 mph when it slammed me right in the testicles."

The first old guy was confused and asked, "What the hell does that have to
do with your dentures?"

"It was the first time in two years that my teeth didn't hurt."