Is there a Dentist in Dallas that will accept children with special needs at the age of 18? If so where?

My daughter has special needs and right now is under the care of a dentist that is addressing her dental needs but when she turns 18 he can no longer accept her as a patient , thus making me find another dentist right away to accommodate her needs. Where should i go? And right now all she has is Medicaid and most dentist will not even accept that as payment , We can not afford a big bill like that without assistance, so what can we do?
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Yes most will, there is no age limit
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