Shyla asks Daniel Jackson if he needs his "glasses". No one on this planet wears "glasses" and the term, "glasses" is an English word and not even universal in N America. Shyla would have no knowledge of the word.
Even though forced to work in a mine under slave conditions (and being covered in dirt), Jack's teeth still gleam snowy-white when grimacing. However, even under the dirtiest conditions, it is possible to maintain oral hygiene. Hundreds of years ago, supposedly primitive tribes-people in Africa kept their teeth gleaming by using a paste made with the ash for fire.