Was just thinking about this while taking a boring regular shower with water. A sonic shower just vibrates at high intensity to pulverize dirt and knock it from your body; but what about oils and lipids and all that other stuff that makes you stinky?
On a side note, I realized that the only time any dental care is brought up, it’s with the ferengi. The race with quite possibly the worst teeth in the galaxy are the only ones seen using cleaning utensils on them.
Schlock Mercenary is a webcomic that actually handles that exact situation regarding the duplicates for torture information. It can be considered a Space Opera like star trek, but with mercenaries.