Does dental insurance usually cover part of the cost of a mouth guard you get at a dentist or periodontist?

I am going to be getting a mouth guard and need to know if dental insurance will cover it. It is for receding gums due to clenching.
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You have to check your policy because every company and policy is different. If you don't know, your dentist should get preapproval and should be able to tell you what you'll be responsible for.
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