This sounds like a theft of service type charge.  She can do one of two things, outside of hiring an attorney.  The first is to mail the payment to the dentist office certified mail.  She will want to keep a copy of the cashed check if they do deposit it in their account.  The second option is to contact the law enforcement agency that is handling the warrant or the district attorney's office that is in her jurisdiction to let them know that she does want to pay and has been trying to pay it.  If she can mail in the payment before talking to them, it will be even better because she will have made a good faith effort to pay the check... as opposed to the many defendants who "promise payment of Friday," and which never comes.  With regard to the second option-- your daughter needs to be careful not to make any admissions.... if she admits that it was theft versus a misunderstanding, then the law enforcement agency or DA's office can use it against her later.  That's why most people want to have any attorney before they talk to the DA's office.  If she cannot afford an attorney, call the district clerk in your county to see if they have a public defender's officer than can help her get the bill paid and the warrant lifted.