Our Team

About Our Office

Greeley Dental Health is located in Greeley, Colorado. Our team of dental specialists includes regular and cosmetic dentists and an endodontist.

Dr. Charles Johnson, DDS

Dr Charles Johnson

Dr. Charles Johnson is a graduate of the University of Nebraska School of Dentistry. In 1979 he received his undergraduate Bachelor of Science degree from Brigham Young University in Provo, Utah. He has been a practicing General Dentist for over 22 years and 18 of those years were spent here in Greeley. Dr. Johnson completed a one-year general dentistry postgraduate hospital residency program in California and then moved to Colorado in 1994. He practiced first in Denver, then in Longmont, and for the last 16 years in Greeley. He has been practicing with Greeley Dental Health since its inception in October 1997. He has completed advanced training in C02 laser surgery and implants.

Dr. Johnson is especially concerned with patient education and disease/decay prevention. Oral health is an important aspect of a person’s general well-being. It can significantly improve the quality of life if it is maintained. He believes in a team effort approach to dental care where the patient and doctor mutually decide and work together to meet the goals of obtaining and maintaining good oral health.

Dr. Johnson is a graduate of Cerinate Smile Design and the Academy of Laser Dentistry in the use of the DEKA Ultraspeed CO2 laser.

Dr. Austin DePorter, DMD

Dr Austin DeporterDr. Austin DePorter is a graduate of Southern Illinois University’s School of Dental Medicine and a member of the American Dental Association. Before attending dental school, he earned his undergraduate Bachelor’s degree in Biology from Augustana College in Rock Island, Illinois. After practicing dentistry in Moline, IL, for several years, he moved to Colorado with his wife, Laura, in the spring of 2016.

Dr. DePorter believes in providing his patients with the best possible dental care. He is passionate about helping people achieve a confident smile through improving oral health. Dr. DePorter prides himself on helping patients understand all of their options, so they can make educated decisions about their personal treatment plans. In his free time, Dr. DePorter enjoys spending time outdoors with his wife, Laura, and their dog, Rez. He enjoys playing video games, trying new foods, and all things nerdy.

Dr. Donald J. Thorne, DMD

Dr Donald ThorneDr. Thorne grew up in Sunnyvale, California (in the San Francisco Bay Area). He attended Brigham Young University in Provo, Utah. Dr. Thorne graduated with a Bachelor’s degree in Biology. He did his dental training at Southern Illinois University School of Dental Medicine in Alton, Illinois and graduated in 1997. While there, he developed a keen interest in the specialty of oral/maxillofacial surgery and decided to pursue further education.

He then entered the University of Nebraska at Lincoln for a one-year fellowship in advanced oral surgery techniques, which included training in the use of I.V. conscious sedation.

In 1998, he moved to Greeley, Colorado. Dr. Thorne says “I chose Colorado because of the beautiful mountains, the outdoor recreation, and the great people here. I enjoy my work with patients and have a great staff to support me.” In his personal time, he thoroughly enjoys music and currently sings with the Greeley Chorale.  He likes to travel and take in the beautiful scenery with his wife, Michele.

Dr. Chris Hahn, DDS, Endodontist

Dr. Chris HahnDr. Chris Hahn received his Masters of Science (MS), Doctorate of Dental Surgery (DDS) and Certificate of Endodontics from the University of Nebraska Medical Center College of Dentistry. He completed his General Practice Residency at the Naval Hospital Great Lakes and later became Dental Command. He has served as a Dental Officer for the United States Navy and was part of USS THEODORE ROOSEVELT (CVN-71) in Bosnia and Iraq. He has also practiced at the Faculty Emergency Clinic of his alma mater, the University of Nebraska Medical Center College of Dentistry. He now practices privately and specializes in endodontics.

Dr. Chelsea Twohig, Periodontist

Dr. Chelsea TwohigDr. Twohig was born and raised in small-town Wisconsin.  She attended the University of Wisconsin-Madison, graduating with a Bachelor of Science in Biology and Spanish.  Rather than immediately entering dental school, Dr. Twohig pursued her passion for Spanish language and culture, spending two years in northern Spain as an English language assistant in high school classrooms.  It was during those two years that Dr. Twohig began to play ultimate Frisbee, which has become the pastime that dominates her free time to this day.

Although Dr. Twohig fell in love with Spain, she felt it time to return to the US and begin the next phase of her academic and professional life, and so she enrolled in the University of Iowa College of Dentistry.  Prior to her periodontal residency program, in the interest of developing her ability to practice dentistry in Spanish, Dr. Twohig completed a two year advanced education in general dentistry residency at the University of Puerto Rico School of Dental Medicine.  She then completed her periodontal residency at Oregon Health and Science University.  Dr. Twohig enjoys all aspects of her work, but specifically enjoys forming relationships with her patients and colleagues.

She and her husband, Derek, recently moved to Colorado as Derek accepted a position at the University of Northern Colorado.  Together they enjoy traveling, snowboarding, and ultimate Frisbee.


Wendy – Office Manager


Roxanne – Insurance and Billing


Ginger- Front Desk


Heather – Front Desk


Hillary – RDH


Kristy – RDH


Antonio – RDH


Tyler – RDH


Arturo – DA


Denise – DA


Nicole – DA


Rosalba – DA


Tammie – DA


Isaias – Sterilization Tech