Endodontics Faculty

Mohamed Ibrahim

Dr. Mohamed Ibrahim

Clinical Associate Professor and Director, Predoctoral Program in Endodontics

Dr. Mohamed Ibrahim (B.ChD., M.S., D.M.D., Ph.D.) is currently an Associate Professor of Endodontics and Director of Predoctoral Program in Endodontics at Marquette University School of Dentistry. He received his dental degree with honors, specialty training and MS in Endodontics and Conservative Dentistry from Mansoura University, Egypt and his Ph.D. in Endodontic Microbiology via a joint supervision program between Mansoura University, Egypt and Universität zu Köln, Germany. Dr. Ibrahim also has a doctoral degree from Universität zu Köln in the field of Hydrodynamic Disinfection in Endodontics. He is a member of the American Association of Endodontics and the American Dental Education Association. His current research focuses on factors affecting clinical outcomes for nonsurgical and surgical endodontic treatment and factors that affect the biomechanical response of natural teeth.

Joseph L. Gaffney

Dr. Joseph L. Gaffney

Clinical Professor

Lance Hashimoto

Dr. Lance Hashimoto

Clinical Professor

Dr. Hashimoto was raised in Hilo, Hawaii and received his Bachelor's Degree in Biology at the University of the Pacific in Stockton, California. He received his Doctor of Dental Surgery Degree from the Marquette University School of Dentistry in 1988.  He completed his Certificate in Prosthodontics from the Marquette University Graduate School in 1990. During his time as a Prosthodontist, he grew more passion for the field of dentistry and wanted to broaden his education. In 2002, he graduated with a Certificate in Endodontics and a Master of Science Degree from the Marquette University Graduate School.  He has since been given the "America's Most Honored Professionals" award for continuous professional recognition- an accomplishment realized by the Top 10% of American Professionals.  Dr. Hashimoto is not only sought after for his knowledge in the dental field, but for his caring and welcoming demeanor. Root canals are his specialty in meeting countless satisfied smiles. He holds the academic rank of Clinical Professor at Marquette University's School of Dentistry.  In addition to being a full time faculty member, he also practices at both Mukwonago Endodontics and Access Endodontics in Brookfield.   His passion and dedication to the field is contagious.

Joseph deGuzman

Dr. Joseph deGuzman

Adjunct Professor

Dr. Joe deGuzman is originally from Menomonee Falls.  He attended Marquette University High School, followed by Marquette University for his undergraduate studies, earning his Bachelor of Science in Biology.  He went on to receive his Doctor of Dental Surgery degree from Marquette University in 1989.  Furthermore, he then completed a year-long hospital residency at the Clement J. Zablocki VA Medical Center.  Dr. deGuzman practiced general dentistry in the Milwaukee area before returning to Marquette University for his specialty training, earning a Master of Science and Certificate in Endodontics in 1997.  He is an associate professor in the endodontics clinic, where he has taught since 1991. He is a member of the Washington-Ozaukee County Dental Society, Wisconsin Dental Association, American Dental Association, and American Association of Endodontists.  Dr. de Guzman is a published researcher in both the Journal of Dental Research and the Journal of Endodontics.  He has achieved diplomate status and is certified by the American Board of Endodontics.  Dr. deGuzman has been named one of the “Milwaukee-Area Top Dentists” every year since 1999.  Outside the office, he enjoys spending time with his family.  He also enjoys golfing and watching basketball. 

Gordon Barkley

Gordon L Barkley III, D.M.D, M.S.

Adjunct Assistant Professor

Dr. Barkley graduated from Midwestern University College of Dental Medicine - Illinois in 2015, and from Marquette University School of Dentistry with a certificate of endodontics and a masters of science in dentistry in 2017. He has taught part-time within the endodontic department at Marquette University School of Dentistry and as a faculty at OSF’s general practice residency program in Peoria, IL since graduating residency. A Diplomate of the American Board of Endodontics, Dr. Barkley has lectured nationally and is published in the Journal of Endodontics. He owns a private practice limited to endodontics in his hometown of Peoria, IL.

Enida Haxhia

Dr. Enida Haxhia, D.D.S, M.S.

Adjunct Assistant Professor

Dr. Haxhia attended the University of Missouri in Kansas City for her Doctor of Dental Surgery degree. After finishing a one-year General Practice Residency, she then worked as a general dentist in the Chicago area for several years before deciding to pursue her passion for endodontics. Dr. Haxhia received a Certificate in Endodontics and a Master of Science in Dentistry degree from Marquette University School of Dentistry in 2021. The same year, she was published in the Journal of Endodontics for her research in outcomes of endodontic nonsurgical vs surgical retreatment. Dr. Haxhia works full-time as an endodontist at a private practice in Chicago and returns to Marquette University School of Dentistry endodontics department on a part-time basis.

Jon Irelan

Dr. Jon Irelan

Adjunct Assistant Professor

Dr. Jon Irelan graduated Magna Cum Laude from Marquette University School of Dentistry, earning his D.D.S. in 2013. He later completed a three-year prosthodontic residency in 2016 at Marquette University School of Dentistry earning a master’s degree, and continued as the sole prosthodontist for a 60-practice dental group where he managed complex and esthetically-driven cases.  Dr. Irelan went on to complete his endodontic residency in 2018 at Marquette University School of Dentistry earning an additional master’s degree.  He is an active member of the Tennessee Dental Association, Nashville Dental Association, American Dental Association, American College of Prosthodontists, American Association of Endodontists, and the American Board of Endodontics. Dr. Irelan is proud to represent his profession as a Board-Certified Endodontist.  In addition to clinical practice, Dr. Irelan is passionate about speaking before his colleagues in the dental community to further the profession, and even lectured at the 2018 American Association of Endodontists Annual Session in Denver, Colorado and again in 2019 in Montreal, Québec, Canada.  He has also been published multiple times in peer-reviewed journals and lectures internationally on microsurgical procedures as an official speaker for Zeiss Meditec, a global leader in dental and medical microsurgical systems and optics.

Thomas Jahnke

Dr. Thomas Jahnke

Adjunct Assistant Professor

Dr. Thomas Jahnke, a native Wisconsinite, graduated with honors with a Bachelor’s Degree in Biology from UW - La Crosse. He went on to receive his D.D.S from the University of Indiana School of Dentistry, where he was welcomed to be a member of the National Dental Honor Society, OKU. He is a board-certified Endodontist whose focus is pain management and therapeutics. Dr. Jahnke served our country in the Army, where he practiced as a general dentist before advancing as a specialist in Endodontics by completing his endodontic residency at Fort Bragg in North Carolina. He received his Master’s Degree during residency with research on the Adoption of Endodontic Technological Advancements and received the acclaimed "Dentsply Sirona Award" for his peer-reviewed research presentation at the American Association of Endodontists annual meeting. One of his military notes of recognition is the "Army Commendation Medal", obtained for meritorious achievement and clinical service.  Dr. Jahnke took his endodontic training to Fort Drum in New York and served as the Chief of Endodontics there which, along with seeing a wide variety of root canal needs, and performing the most challenging endodontic procedures, involved overseeing and mentoring restorative dentists on the art of endodontic therapy. He was additionally the resource for dental resorption and brings his knowledge of the periodontal/endodontic resorptive connection to our practice. Dr. Jahnke further added to his endodontic and patient care talents while in private endodontic practice in upstate New York. He is a member of the American Association of Endodontists, American Board of Endodontics, American Dental Association, Greater Milwaukee Dental Association, and Waukesha County Dental Society.

Maksim (Max) Montatskiy

Dr. Maksim (Max) Montatskiy

Adjunct Assistant Professor

Dr. Maksim (Max) Montatskiy graduated from the University of Illinois at Chicago, earning a Bachelor of Science degree in biology and a minor degree in chemistry, in 2008. In 2010, he earned a Master of Science degree in biomedical science and received a certification in healthcare administration at Rosalind Franklin University of Medicine and Science. In 2015, Dr. Montatskiy graduated magna cum laude, earning his D.M.D. degree from the University of Illinois at Chicago, College of Dentistry.  Dr. Montatskiy worked in private practice as a general dentist in Southeastern Wisconsin before attending Marquette University, School of Dentistry and earning a Master of Science degree and Certificate in Endodontics. Dr. Montatskiy’s research involved injectable gels with potential use in endodontics. He is currently a part-time surgical sciences faculty member within the Endodontics Department at Marquette University School of Dentistry, where he provides guidance to both endodontic residents and dental students. He has provided volunteer dental services in both Illinois and Wisconsin through Goldie’s Place dental clinic, Mission of Mercy, and Give Kids a Smile foundation. Furthermore, he is a member of the American Association of Endodontists and the American Dental Association.

Alex Moore

Dr. Alex Moore

Adjunct Assistant Professor

Dr. Moore received his Master of Science in Endodontics from Marquette University School of Dentistry in 2018 and practiced in Chicago for two years before opening a practice in Rockford, IL. He enjoys playing tennis, golf, traveling and “searching for the best Old Fashioned in Chicago.”

F. Kris Olsen

Dr. F. Kris Olsen

Adjunct Assistant Professor

Dr. Olsen received his dental degree at Emory University in Atlanta, GA. Afterwards, he completed his specialty training in Endodontics along with a Master of Science degree at Marquette University.   In addition to his time at the office, Dr. Olsen also holds a part-time faculty position at Marquette University School of Dentistry, where he was previously the Director of the Pre-doctoral Endodontic Program.   His background includes research, lecturing and publishing papers on current topics in the field of Endodontics.  He also teaches essential clinical skills to both the dental students and post-graduate residents.  Dr. Olsen feels that the continuous pursuit of knowledge is critical in being able to assist his patients with the most up-to-date treatment choices possible.