He studied Biology at the University of Missouri in Columbia. In 1994, he received his doctorate in dental medicine at Southern Illinois University School of Dental Medicine where he received the school honor awards in Dental Research, Fixed Prosthodontics, Dental Materials and Endodontics. He was also the president of the Delta Sigma Delta dental fraternity and was inducted into Phi Kappa Phi National Academic Honor Society and the Omicron Kappa Upsilon National Dental Honorary.

Dr. Holtzmann received his Certificate of Specialty in Endodontics and Masters in Oral Science at The University of Iowa. After his residency, he joined the faculty at Southern Illinois University School of Dental Medicine and Saint Louis University as an Assistant Clinical Professor in the Department of Applied Dental Medicine and Postgraduate Endodontic Program. During his time in dental school, graduate school and teaching, Dr. Holtzmann authored and co-authored several scientific papers as well as authoring a chapter in an endodontic text book. Dave moved to Colorado in January of 2000 to join Endodontics of Colorado, L.L.C.

He is active in several charitable organizations including Kids in Need of Dentistry, the Howard Dental Center, Donated Dental Services and others. Dr. Holtzmann is a member of the Metro Denver Dental Society, the Colorado Dental Association, the American Dental Association, and the American Association of Endodontists.

Dave lives in Parker Colorado with his wife, Krista, and their two sons. They enjoy many outdoor activities together including swimming, hiking, biking, basketball and volleyball.