A dentist noticed that his next patient, a little old lady, was very nervous, so he decided to tell her a little joke as he put on his latex gloves.
"Do you know how they make these gloves?" he asked.
"No, I don't", she replied.
"Well," he spoofed, 'there's a building here in Canada with a big tank of latex, and workers of all hand sizes walk up to the tank, dip in their hands, let them dry, then peel off the gloves and throw them into boxes of the right size."
She didn't even crack a smile.
Oh, well. At least I tried", he thought.
But about five minutes later, during a delicate portion of the procedure, she suddenly burst out laughing.
"What's so funny?" he asked her.
"I was just envisioning how condoms are made!"