Welcome to Our Practice

Dentist St. Johns, MI - Christine M. Mason, MS, DDS & Ona Erdt, DMD, MSHS, CDA

Christine M. Mason DDS has been working with patients in the St. Johns area for over twenty-five years providing excellent dental care. Dr. Mason expertise in dentistry coupled with genuine concern for his patients results in a very caring and exceptional patient experience.  Our talented dental team is dedicated to providing comfortable and prompt care. Our goal is to keep your teeth healthy and your smile bright.

This website provides you with an overview of our practice and the field of dentistry. As you navigate the site, you'll find information about Dr. Mason practice philosophy, our St. Johns office location, insurance policies, and appointment scheduling procedures. Please browse the site at your convenience and feel free to contact us with any questions or to make an appointment.

You'll find valuable information on this website about dental problems, diagnoses and treatments, and the services we offer, such as crowns and bridges and fillings. We believe informed patients are better prepared to make decisions about their health and well-being. We encourage you to review this information to help you understand any health concerns you may face.

Meet the Doctors

  • Christine M. Mason DDS

    - Masters degree focused on dental materials; member of the International Association of Dental Research. Has lectured nationally and internationally.
    - Graduate of the Dawson Academy for Advanced Dentistry.
    - Current participant in the Kois Center for aesthetic, implant and restorative dentistry.
    - Over 600 hours of continuous education in dentistry.
    - Focused on Health-centered dentistry and the mouth-body connection
    - Member ADA, MDA, Central District Dental Society, AAOSH (American Academy for Oral and Systemic Health)
    - MDA Trustee

    Click here to view the full CV

  • Ona R.
    Erdt, DMD, MSHS, CDA

    Celebrating a diverse 19-year career in dentistry, Dr. Ona coalesces her experiences as a dental assistant, dental educator, dentist, dental product evaluator and clinical editor into one unique viewpoint. Dr. Ona graduated in 2002 with an AAS in Dental Assisting. It was there that a love affair with all things dental was born. Always wanting to learn more about the art and science of dentistry, she went on to graduate from dental school. She obtained her DMD as well as completed a MSHS degree, majoring in Health Professions Education, from Western University of Health Sciences in Pomona, CA. After practicing dentistry with Indian Health for a number of years, she now brings her diverse experience and passion to the St. Johns community.

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Systemic Health and Dentistry

Our Location

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Hours of Operation

Our Regular Schedule


9:00 am-5:00 pm


8:00 am-5:00 pm


8:00 am-5:00 pm


8:00 am-5:00 pm


8:00 am-12:00 pm