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Your mention about the gums being darker red near the teeth? It's typically seen when there is a bit more build up of dental plaque, which we all can & do get. Try to brush it more and better & longer time frames, and with a soft bristle brush - it should return to natural color within a week or so!
With regard to the two back teeth turning blackish? It sounds like and likely may be a couple of cavities that may well need a couple of tooth colored fillings in them.
Does this make sense?
Yes, the plaque is causing the gums to be inflammed & more red - you can stop this with extra care though!
The bottom blackened areas, may well be silver fillings only (from the picture angle, it was difficult to say with certainty). If silver fillings are in for years, the teeth do turn darker. I have some of that. It doe NOT mean you necessarily need to change the silver fillings though. Ask your Dentist about the blackened look when you see him or her for your next Dental check up. So, you may not have any cavities at all? Could very well just be silver fillings!
From the 2nd picture I couldn't detect any crooked jaw. Could be so, but I could see it from the picture, Sir.
Sir, does the above make sense?
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*NOTE: I want to make certain your concerns are addressed, so please do not hesitate to ask further, if need be OK?
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