Our Doctors

Meet Our Doctors


Dr. Jeff Mastroianni

Jeff believes in always giving 100% both in the office and in his personal life. Whether that’s coaching his daughter’s soccer team, or motivating and inspiring his orthodontic team on a Monday morning, Jeff is fully committed to anything he takes on. You will often find him straightening teeth at the office or out as a leader in his community - both jobs are always done with a drive and passion to help others be their best.

Dr. Jeff feels privileged and blessed every single day to be a member of this great profession! Beautiful smiles build confidence in so many ways and he feels strongly about the lasting value of orthodontic treatment.

Dr. Julie McCray

Dr. McCray grew up in Iowa and has wanted to be an orthodontist since she was a patient of the University of Iowa orthodontics department as a middle schooler.

She attended the University Of Iowa as an undergrad with a major in Biomedical Engineering while working as a research assistant in the orthodontic department.

Meet Our Doctors-Dr. Julie
Dr. Julie Ruppel from Amazing Smiles

Dr. Julie Ruppel

We are excited to announce Dr. Julie Ruppel joined our practice, and she will be working primarily at our Clayton location, and occasionally at our Glen Carbon and O'Fallon locations. The entire Amazing Smiles team is thrilled to have her on board!

Being an orthodontist is Dr. Ruppel's passion! She genuinely cares about her patients and wants to be accessible to them during their orthodontic journey. She takes pride in providing excellent care in a warm and friendly environment. She uses the latest technologies to make your orthodontic experience as efficient, effective, and painless as possible.


We look forward to helping you keep your smile amazing!