Brief Answer:
Malaligned teeth, orthodontic treatment, gum surgery

Detailed Answer:
Thanks for your query. I have gone through your query.
As far as the space between teeth is concerned, it can be because of malaligned teeth secondary descrepancy between teeth size and jaw size. The other possible cause can be because of the gum infection making the teeth weak.
Nothing to be panic, consult an oral physician and get it evaluated. Mean while you can send the images of your teeth and your details like age sex and medical history, so that I can give you better diagnosis and treatment plan.
If it is a malaligned teeth secondary to jaw size and teeth size descrepancy, then it can be corrected by braces or orthodontic ticket treatment. If it is secondary to gum infection then it can be treated with gum surgery.
I hope I have answered your query. If you have any queries reply me back. Take care

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