About the Doctors


Dr. Mandelaris attended the University of Michigan from undergraduate through dental school. In 1999, he completed a three-year post-graduate residency program in Periodontology at the University of Louisville, School of Dentistry, where he also obtained a Master of Science (M.S.) degree in Oral Biology.

Dr. Mandelaris is a Diplomate of the American Board of Periodontology and has served as an examiner for Part II (oral examination) of the American Board of Periodontology certification process. He has served as an Assistant Clinical Professor in the Department of Oral and Maxillofacial Surgery at Louisiana State University, School of Dentistry (New Orleans, LA) and currently serves as an Adjunct Clinical Assistant Professor in the Department of Graduate Periodontics at the University of Illinois, College of Dentistry (Chicago, IL). He is a Fellow in the American College of Dentists and the International College of Dentists.

Dr. Mandelaris serves as an ad-hoc reviewer for the Journal of Periodontology, the International Journal of Periodontics and Restorative Dentistry, and the International Journal of Oral and Maxillofacial Implants. He has published in several peer-reviewed journals such as the International Journal of Periodontics and Restorative Dentistry, Compendium for Continuing Education in Dentistry, Practical Procedures and Aesthetic Dentistry, the Journal of Periodontology, Clinical Advances in Periodontics, and The Journal of Oral and Maxillofacial Surgery. He has also contributed several chapters in five different textbooks used worldwide on subjects related to computer guided implantology, CT diagnostics and, most recently, Surgically Facilitated Orthodontic Therapy (a book he edited and which he authored the chapter on surgical therapy). He is a Past President of the Illinois Society of Periodontists and has served on several committees for the American Academy of Periodontology.

In 2014, he was one of 52 periodontists worldwide selected to participate in the American Academy of Periodontology’s commissioned Periodontal Regenerative Medicine World Workshop on Emerging Regenerative Approaches for Periodontal Reconstruction. A nationally recognized expert, he was appointed by the American Academy of Periodontology in 2015 to co-chair the best-evidence consensus workshop on the use of CBCT imaging in Periodontics as well as co-author the academy guidelines. He holds memberships in many professional organizations, most recently including the American Academy of Restorative Dentistry and American Society of Bone and Mineral Research.

Dr. Mandelaris has been a part of the attending medical staff at Advocate Lutheran General Hospital, Department of Surgery, and Division of Dentistry since 2000. In addition to his medical staff appointment, he has actively participated on the head and neck oncology team and helped develop oral health care protocols for patient management. He is licensed to deliver intravenous (I.V.) conscious sedation for patient comfort during surgical therapy.

Download CV for George Mandelaris, DDS, MS, Diplomate, American Board of Periodontology, Attending Medical Staff, Lutheran General Hospital


Dr. Alan Rosenfeld, attended the University of Illinois, College of Dentistry, where he graduated with honors and awards for academic excellence. Following his dental training, Dr. Rosenfeld completed a general practice residency at Michael Reese Hospital in Chicago. He is hospital trained and licensed to provide intravenous sedation for patient comfort.

In 1977, Dr. Rosenfeld completed his specialty training in periodontics at the prestigious University of Pennsylvania. From 1977-1983, he served as an Associate Professor of Periodontics and Program Director of Graduate Periodontics at Northwestern University Dental School.

In 1982, he qualified to become a Diplomate of the American Board of Periodontology. This certification is held by less than one third of all periodontists. In 1995, he was inducted into the American College of Dentists, an honor held by fewer than three percent of all dentists.

Dr. Rosenfeld has lectured extensively both nationally and internationally and presented several hundred presentations on dental topics throughout his career. He began using CT scans for diagnosis and treatment planning in 1987, nearly two decades before its wide acceptance in dentistry. Most notably, his groundbreaking work with Dr. Richard Mecall and later Dr. George Mandelaris has set the educational and professional standard for the use of CT scans for diagnostic purposes, surgical treatment planning, computer guided implant placement, and determination of prosthetic outcomes in the dental profession. He has published in numerous peer-reviewed journals and textbooks and is considered an expert in this field. Dr. Rosenfeld’s most current accomplishment is as editor and author of multiple chapters for the internationally recognized textbook entitled The Art of Computer Guided Implantology.

Dr. Rosenfeld serves on the medical advisory board of Materialise Dental, a Belgium company which manufactures SimPlant software for CT scan analysis and surgical implant guides. He is also a mentor to the SimPlant Academy, a website devoted to this field. Dr. Rosenfeld lectures for Biomet 3i, an international dental implant manufacturer on the topic of CT guided surgery.

Dr. Rosenfeld is actively involved in numerous professional organizations, including the American Academy of Periodontology, the Illinois Society of Periodontology, the Midwest Society of Periodontology, the Academy of Osseointegration, the American Dental Association, the Illinois State Dental Society and the Chicago Dental Society.

Dr. Rosenfeld has been a member of the attending medical staff in the Department of Surgery, Division of Dentistry, at Advocate Lutheran General Hospital for nearly 30 years. He is also a Clinical Professor in the Graduate Periodontics Department at the University of Illinois – College of Dentistry, where his chief responsibility is teaching residents in periodontal plastic surgery and implant surgery.

Download CV for Alan L. Rosenfeld, DDS, FACD

Bradley S DeGroot, DDS, MS

Dr. Bradley DeGroot grew up in Green Bay, Wisconsin. He attended Marquette University where he majored in Biological Sciences and graduated summa cum laude. He then attended dental school at Marquette University where he also graduated summa cum laude. Following his graduation from dental school, Dr. DeGroot attended the University of Texas Health Science Center San Antonio (UTHSCSA) for a three-year residency program in Periodontology and Dental Implantology. While at UTHSCSA, Dr. DeGroot earned his specialty certification as well as obtaining a Masters of Science in Dentistry. His clinical research focused on improving treatment protocols for immediate implants placed in the esthetic zone.

Dr. DeGroot holds dental and specialty licensure in the State of Illinois. He is an active member in the American Academy of Periodontology, the International Team for Implantology, American Dental Association, Illinois Dental Association, Illinois Society of Periodontists, Midwest Society of Periodontology, and the Chicago Dental Society. Dr. DeGroot is also a member of the attending medical staff in the Department of Surgery, Division of Dentistry, at Advocate Lutheran General Hospital.

Dr. DeGroot is in private practice at Periodontal Medicine & Surgical Specialists, LTD in Park Ridge and Oakbrook Terrace, Illinois. He limits his practice to Periodontology, Dental Implant and Bone Reconstruction Surgery.

Download CV for Bradley S DeGroot, DDS, MS


Dr. Rosenfeld and Dr. Mandelaris occasionally need the assistance of an office anesthesiologist for certain periodontal and implant surgical procedures. We have privileges for periodontal and oral surgery procedures in the operating room at Advocate Lutheran General Hospital. However, many of these procedures are better suited in our office based setting rather than the O.R. We offer general anesthesia and deep level sedation during extensive surgical procedures for patients where mild-moderate IV conscious sedation is not adequate. Dr. Zakaria Messieha serves as our office based anesthesiologist.

Dr. Messieha received his DDS (Doctor of Dental Surgery) degree from The Ohio State University. He then completed a General Practice Residency at the College of Virginia Medical Center and McGuire VA Medical Center in Richmond, Virginia. From there, he went to Long Island Jewish Medical Center, where he completed a residency in Anesthesiology.

After working in an office-based practice for almost a year and a half, Dr. Messieha came to the University of Illinois at Chicago, where he worked full-time between the College of Dentistry and the Anesthesiology Department.

Dr. Messieha has lectured nationally and internationally on Anesthesiology and Pain Anxiety Control. He has several published papers and abstracts. He continues his academic post on a part-time basis as a Clinical Associate Professor of Anesthesiology both at the College of Medicine and the College of Dentistry. Dr. Messieha has filled leadership positions at the National and State levels including:

  • President of the Illinois Dental Society of Anesthesiology
  • Secretary and member, the Board of Directors of the American Dental Board of Anesthesiology
  • Chair, The American Dental Education Association Council on Hospitals and Advanced Education Programs
  • Chair, The American Dental Education Association Section on Anesthesiology, Oral Surgery and Hospital Dentistry

Board Certifications:

  • Diplomate, National Board of Anesthesiology
  • Diplomate, American Dental Board of Anesthesiology
  • Diplomate, National Dental Board of Anesthesiology
  • Certified Advanced Cardiac Life Support and Pediatric Advanced Life Support instructor by the American Heart Association

Feel free to learn more about Dr. Messieha by visiting his website www.officeanesthesiology.com.



Dr Angelopoulos is a diplomate of the American Board of Oral and Maxillofacial Radiology and a fellow of the International College of Oral Implantologists. He has held University appointments at University of Missouri-Kansas City, School of Dentistry (assistant professor 08/02-02/07) and at Columbia University, College of Dental Medicine (associate professor and director of Oral and Maxillofacial Radiology 03/07-12/10). Currently, he holds an Oral and Maxillofacial Radiology consultant’s appointment at James J. Peters VA Medical Center (Bronx NY).

Dr Angelopoulos is serving as the Executive Director of the American Academy of Oral and Maxillofacial Radiology (AAOMR) since 10/2009 and has served as an officer of the AAOMR for several years. Moreover, he is the Associate Editor of OOOOE (the official journal of the AAOMR). He has published over 40 scientific papers and has spoken in several conventions and CE courses, nationally as well as internationally, on a variety of radiology topics. His main research interests include diagnostic ultrasound, cone beam computed tomography, implant imaging etc.

Dr Angelopoulos maintains a maxillofacial radiologic consultation practice, Maxillofacial Radiology Consultants (www.mfr-co.com), in New York City (Manhattan), NY.


Richard is the head radiology technologist for our cone beam computed tomography (CBCT) imaging center. He is a registered radiology technologist, holding specific credentials in Computed Tomography (CT). He has been in the radiology field for over 20 years and began specializing in dental CT scans13 years ago. Richard’s training and experience as a radiology technologist ensures that patient positioning, radiation dosing and image acquisition for both digital panorex and CBCT imaging is the very best. He works closely with Dr. Christos Angelopoulos, who is our oral and maxillofacial radiologist reading every panorex and CBCT volume to ensuring the highest standards in radiology interpretation for patients. Our CBCT imaging center is also a SimPlant Master center which allows processing of all CT exams into an implant planning software program on site (i.e. Simplant®).

Richard’s accomplishments with Simplant® reformatting and segmentation have earned him recognition throughout the dental community as an expert, training local offices and staff on the software. Richard’s primary concern is providing excellent patient care with greatly reduced radiation exposure, while maintaining exceptional image quality.