As-salaamu `alaykum.
You've asked us to answer you, well here is my answer. Firstly, I don't live in Egypt or another Muslim land at that, I live in UK. Secondly, like a Muslim man is suppose to, I grow my beard.
Now you haves asked why 90% of bearded guys cheat and don't treat people well?! Well firstly, that is a very serious stereotype, and unless you've met 100% of bearded Egyptian Muslims, it doesn't hold much water. It would be more correct to say that many/most of those bearded Egyptian's you've met are like that, and not to generalise. Also, it is very strange as I have seen the opposite of what you claim be the case, where-ever I have been in the world.
As for Egypt then I was dissapointed, I've been there twice and not once did I meet or even see a bearded Muslim man where I was, yet I met plenty of treacherous, cheating, money hungry people. Even when I went to Morocco, I sat in a cab with many Taxi-drivers and they wouldn't turn on there meters, in attempt to trick, fool and overcharge me and other tourists, yet EVERY bearded taxi-driver turned on his meter without a single fuss!
For the degree I'm currently studying, there is less than a hand-full of brothers with beards, and half of them have not only achieved high-grades, but are also known to be the most hard-working students in my year and have even been rewarded for their excellence with prizes! That is the opposite of what you have described, so the least that can be deduced is that the problem is relative to where you live!
In terms of work, I have worked in trade as well as IT, and again, the beard has been a mark of trustworthiness and excellence, let me ellaborate. In IT, 2 of my old directors had beards as well as a manager, and they were in my opinion, the most dedicated workers I have seen to date. Tasks done, not on time but way before time, and every second utilised for work and not loafing and time-wasting. They would get up with us and attend the masjid for the jama`ah so they weren't compromising their work for deen. They were role-models for other Muslims as well as kuffaar, some of our colleagues even took keen interests in Islaam.
In standard trading companies I've worked in, again, the most just and fair businessman I have seen, has a beard and generally speaking, if a Muslim man who is growing a beard proves to be a liar with respect to trade and isn't trustworthy, he is looked down upon as a despicable individual (as he is naturally expected to fear Allaah more). Even customers, most customers I've dealt with, the bearded ones are the ones who don't try to cheat us, as oppose to sadly many other Muslims and many (I didn't say all) non-Muslim customers who I noticed lie like there's no tomorrow. These are observations I've noticed throughout my life.
So again, what I'm presenting is the opposite of what you claim, so of course every area is effected differently.
As for the sisters, then I can't say much, although I assume that most veiled sisters whose oral health conditions are poor as you mentioned, are either poorer, older or generally more traditional. The one who fears Allaah, with `ilm knows about cleanliness and its station in Islaam. Perhaps others can contribute to this matter better than I.
EDIT: Isra, the initial poster is a sister.