How we close are needle size tooth gaps?

Orthodontia: I can only assume that you are asking, "how do you close small gaps between the teeth?" i believe that the best way to close naturally occurring diastemas between healthy teeth is with braces. Braces are best done by a specially trained dentist called an orthodontist. Ask your current dentist if you are a candidate for orthodontia.

Orthodontia: Spaces between the teeth are usually closed with orthodontics. Consult with your local dentist to see if this treatment is right for you.

Closing spaces: If the teeth are normal in size & harmonious & the occlusion (bite) has resulted in spaces, orthodontic treatment is usually your best option. If your occlusion is basically normal & you have some minor spaces between your front teeth only, in some cases, minor tooth colored bonded fillings may be a reasonable option. Your orthodontist can determine what is best for your particular circumstances.