Glass broke in dishwasher sand grain sized shards. if any got in my mouth would i know? am scared that it will be scratching the inside of my mouth without me feeling it, making scar tissue which will in turn make my cheeks look fat. surely possible?

Stop obsessing: You've created a scenario in your own mind that is simply not factual. Sand sized glass particles will easily rinse off dishes if you wash them before use. You would have to use considerable force for sand-sized particles to penetrate oral mucosa. Massive trauma required to cause scarring. Massive scars required to change cheek shape. See your Dentist for more information.

No worries: The broken pieces and shards of glass wind up in the appliance's drain.

Irrational fear: You're not going to get any glass in your mouth unless you lick the drain. And since you're not going to do that, no worries. Empty the drain into the garbage and rinse off all dishware in the sink before using.