Can it be safe for provider to use a makeup brush after micro needling?

The simple answer to your question is no.  Your skin after microneedling has small microchannels open for several hours and is susceptible to foreign substances getting into those channels. We actually saw a patient from another practice who put a Zinc suncreen on immediately after a microneedling and developed thousands of small inflammatory papules that lasted for over a week. Powder or makeup is forbidden until the next day.  We tell our patients to only use pure Hyaluronic Serum for the first 24 hours.  After that, anything goes except for scrubs, exfoliators, and Retin A.

I agree that unless it is a single use brush which is discarded, it should not be used following microneedling.BestDr. Karamanoukian