Could I use dental wax to cover up my cavity?

Of course, and . Of course you can. You can also place paneling over termite rotted walls, plastic bags on your leaking roof, chewing gum on a leaking water pipe, scotch tape on a hole in your garden hose, duct tape on your muffler pipe, etc. None of theses "fixes" really does anything. You know what you need to do. So go make that phone call to the dentist right away.
Bad idea. All you will do is trap the bacteria that caused the cavity, allowing them to make the cavity worse leading to an abscess. Dental wax is just what it's name says, it's wax designed to pad up new dental appliances such as braces. It has no magical or medicinal properties. The best thing you can do is see dentist to rx the cavity before it gets out of control.
Really??? Trying the treat the symptom/cavity and not the source is predisposing you to all kinds or pain and suffering later. If it is a temporary fix while out of town, etc., maybe, but get to a dentist asap and deal with it professionally!

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