Unparalleled Support

What sets OU's advanced dentistry residency program apart from other programs is its strong clinical component, coupled with the support of an outstanding faculty to help guide and educate our residents. The residents have the advantage of working in our clinic with faculty, which hold specialties in Endodontics, Prosthodontics, Periodontics, Oral Maxillofacial Surgery and Oral Pathology. Our goal is to develop a clinician that has a strong background in restorative dentistry to better serve their future dental needs of their patients. 

Program Director, Phoebe Vaughan, DDS

A native of Oklahoma City, Dr. Vaughan earned her undergraduate degree in biology and music from the University of Central Oklahoma. She graduated with her Doctor of Dental Surgery degree from the University of Oklahoma College of Dentistry and completed the Advanced Education in General Dentistry residency, also at OUCOD. Following graduation, she joined Dr. Shannon Griffin in private practice. Their practice is committed to the same type of high quality, comprehensive dentistry taught and practiced in the AEGD program. In addition, she joined the faculty of OUCOD in the Department of Operative Dentistry as a part-time Clinical Instructor. In 2015, she began teaching in AEGD, and assumed the role of Assistant Director. This year, she was appointed as Director of OU AEGD, and is excited to lead the program. Serving the community through dentistry is her passion. She is active in several dental and statewide activities that target those with unmet dental needs. Because of her commitment to the dental profession, education, and service, she received the "Young Alumnus of the Year" Award in 2013 from the OUCOD. She is a board member and volunteer dentist with D-DENT, a charity that provides free dental care to low-income elderly and disabled Oklahomans. In addition, she is the volunteer clinic dentist at Baptist Mission Center and a Lead Dentist in the OKMOM Restorative section.

Assistant Director, Shannon L. Griffin, DMD

A native New Mexican, Dr. Griffin graduated from Tufts University School of Dental Medicine in 1996.  She came to Oklahoma to be a resident in the AEGD program and after completion of the program stayed for an additional year earning a Certificate in Advanced Comprehensive Dentistry.  It was during her two years of residency that OU AEGD implemented a surgical implant protocol. Upon completion of the program, she opened a private practice in Edmond, Oklahoma. At the same time, she accepted a position at the University of Oklahoma as a clinical instructor in Oral Diagnosis, Restorative Dentistry and AEGD. She is a CEREC certified trainer and continues to guest lecture at Tufts. She has volunteered in the community by serving the Oklahoma City Zoo. She is an active member of the Oklahoma County Dental Association, having served as a Board Member multiple times. Dr. Griffin has served the Oklahoma Mission of Mercy since 2010 and has been a Lead Dentist in the Restorative section from 2011-2015 and served as the State Chairman of OKMOM in 2016. She has given many continuing education presentations throughout the local community.  Her private practice experience, coupled with her background in AEGD and clinical teaching experience, offers a great value to AEGD program at the University of Oklahoma. Dr. Griffin is a Fellow of the prestigious Pierre Fauchard Academy, and the American College of Dentists. She had received the ODA Presidential Leadership Award and the University of Oklahoma College of Dentistry Outstanding Part Time Faculty Award. She is currently serving as the Vice President of the Oklahoma Dental Association.

Paul Mullasseril, DDS

Dr. Paul Mullasseril completed his residency in Prosthodontics at the University of Oklahoma in 1994. He then completed a Fellowship in Maxillofacial Prosthetics at M.D. Anderson Cancer Center in 1996. That led to his return to the department of Removable of Prosthetics at the OUCOD where he was appointed and served as Director of Maxillofacial Prosthetics until 2008. From 2008 till 2011 he taught at Eastern Washington University. He returned to OUCOD in July 2011 and was appointed Chair of Restorative Dentistry. Twice, in 2000 and 2014,  he was awarded the Outstanding Full Time Faculty Award from the Student Council, OUHSC. He is also a recognized national lecturer having been a Consultant and Key opinion leader for 3M - conducted CE courses for 3M nationally and internationally from 2008 to 2011. Since 2011 he has been a consultant for Park Dental Research and Science. His expertise enables our residents to better understand the importance of sound treatment planning in fixed and removable prosthodontics. He also teaches the significance of proper case selection and design for restoring a variety of implant supported  restorations.

Lars Bouma, DDS

Dr. Bouma is a Diplomat with the American Board of Prosthodontists.  He has been in private practice in Oklahoma City since 2006 and prior to that he spent 11 years in the United States Air Force with stops at Lackland Air Force Base in San Antonio, TX and Offutt Air Force Base in Omaha, Nebraska. During his time in the Air Force, Dr. Bouma served as Chief of Prosthodontics, Dental Laboratory Flight Commander, and Assistant Director for the AEGD Residency. He separated from the United States Air Force as a Lieutenant Colonel, and has since been in private practice in Oklahoma City. His knowledge of all areas of dentistry, especially the surgical aspects, greatly bolsters the educational and clinical components of OU AEGD.

Taylor Barton, DDS

The newest member of our faculty, Dr. Barton has recently received his Certificate from the OU AEGD. He is a distinguished graduate of the University of Oklahoma College of Dentistry and his year in AEGD has exemplified why he came to our program with the highest of recommendations. Prior to attending dental school, Dr. Barton received a Masters of Arts in Dietetics and was trained and worked as a dental laboratory technician. He is in private practice with Dr. Shannon Griffin in Edmond.

Mike Fling, DDS

Michael C. Fling, D.D.S. began his career in dentistry in 1976 as a laboratory technician. He soon discovered a passion for dentistry and entered dental school. He graduated from Oklahoma University College of Dentistry in 1984 and went into private practice in Oklahoma City. In 1988, only four short years after entering the profession, he received the "Young Dentist of the Year Award" from the Oklahoma Dental Association.  His private practice focuses on restorative and cosmetic dentistry, as well as TMJ treatment. As a renowned clinical instructor and guest lecturer, he is consistently on the leading edge of dentistry, and incorporates the latest in dental innovation, technology and techniques into his practice.  Aside from his faculty appointment at OU, he also serves as Associate Faculty at the L.D. Pankey Institute. Dr. Fling recently completed the process to be awarded the title of "Pankey  Scholar." As a member of the American Academy of Restorative Dentistry, the American Academy of Fixed Prosthodontics, and the American College of Dentists, he has lectured throughout the country to dental and laboratory associations and to various study groups on fundamental principles of restorative dentistry and achieving technical excellence.

Barry Greenley, DDS

Dr. Greenley is a distinguished Diplomat of the Federal Services of General Dentistry.  He attended the University of Missouri at Kansas City School of Dentistry while on active duty in the U.S. Air Force. Upon graduation in 1978, he completed a one year General Practice Residency at Malcolm Grow USAF Medical Center, Andrews AFB, Maryland. In 1987, he completed a two-year AEGD program at Keesler AFB, Mississippi. After serving our country for a full military career, Dr. Greenley was recruited to Oklahoma in 1995 where he joined the University of Oklahoma AEGD. He previously served as the Assistant Director of AEGD and has most recently been serving as a General Practice Director for the College of Dentistry. We are very fortunate to have Dr. Greenley in our clinic as a part time faculty and lecturer as he is an avid clinician with extensive knowledge and experience  in fixed prosthodontics, removable prosthodontics, dental materials, and esthetic dentistry.

German Luezas, DDS, MS

Dr. Luezas completed his endodontic training with a Masters of Dental Science Degree at the University of Connecticut after finishing dental school and a 2-year residency in Advanced Education in General Dentistry. Prior to attending residency, he practiced as a general dentist where he was able to find his passion for performing root canals. Now as an endodontist, he has expertise in working with specialists and general dentists. Dr. Luezas enjoys the opportunity to be able to give back to his community, participating with Mission of Mercy and working with special needs patients. Dr. Luezas is a member of the American Association of Endodontics, American Dental Association and Oklahoma Dental Association.

Mark Phan, DDS

Dr. Phan was born in Vietnam and relocated to the United States at a young age. He has since made Oklahoma City his home. Dr. Phan graduated from University of Oklahoma College of Dentistry and stayed for the additional year of AEGD. After completing his residency, he became a faculty member at the Oklahoma University College of Dentistry as well as entering into private practice.  Dr. Phan has volunteered  his time and dentistry on several mission trips around the world to help treat families in need. Dr. Phan has a heart for Third World Countries and is committed to lending a hand every year.


The additional specialists who work with our residents are a combination of faculty from OUCOD as well as experienced clinicians from the local community.  Together, we formulate a program that offers our residents one-on-one attention which helps them build their confidence in their clinical skills.

The support staff is essential in helping our residents transition into a private practice-like setting. Each AEGD resident will work a chairside dental assistant throughout the program. Working with the assistants allows the resident to provide quality care efficiently in a setting that better reflects the true working environment of dentists in private practice. 

The program also employs an office manager who supervises three office employees and seven clinic employees. The experienced office staff handle appointments, billing, insurance, and other managerial tasks. Interaction with a working business office gives the residents experience in practice management.

The AEGD resident will complete the normal laboratory work that a private dentist might do: trimming dies, pouring impressions mounting cases and learning to discuss their cases with the technician. The resident will have the ability to work with a variety of dental laboratories to better understand the value of quality restorations and the expertise and strengths of each technician.