Richard Gesker, Chief Dental Officer, DMD, MBA

Chief Dental Officer and dentist Richard Gesker started his career as a Lieutenant in the United States Navy Dental Corps after graduating from Temple University's School of Dentistry and School of Business. He joined Mary's Center in early 2010 after four years in the military and three years in private practice. He is responsible for delivering high-quality dental care and maintaining the care delivery and management model for all administrative and clinical staff. His commitment to continuing education is supplemented by the various federal and private research projects that he oversees. In March, 2014, Dr. Gesker was announced as one of the two winners of the DOCS Education's 2014 Sedation Dentist of the Year Award.


Dr. Ashley FaganAshley Fagan

Dr. Ashley D. Fagan graduated from the University Of Maryland School of Dentistry and is a licensed dentist in both Maryland and Washington DC. While in school, Dr. Fagan was a recipient of the Dr. Charles W. Hennessey Scholarship Fund and was also one of the recipients of the Dean’s Community Service Award. She is a member of the Gamma Pi Delta Prosthodontic Honor Society and was also a CAD/CAM Clerk, helping with the computer-aided design and computer-aided manufacturing of dental prosthetics. She enjoys eating, traveling, working out and spending time with friends and family.



Dr. James GriffinJames Griffin, DDS

Dr. James Griffin, who joined Mary’s Center in September 2017, graduated from the University of Maryland School of Dentistry and is a licensed dentist in both Washington, DC and Maryland. Dr. Griffin is originally from Connecticut, where he was in private practice early in his career. He relocated to the Mid-Atlantic area and has worked for a number of years in hospital-based dentistry, convalescent home dental care, and in a private practice setting. Dr. Griffin is a seasoned clinician, who enjoys working with the diverse and underserved populations cared for by Mary’s Center. He enjoys boating, kayaking and biking, and is a huge Maryland Terrapin fan.


Rodrigo Guevara, dentist at Mary's CenterRodrigo Guevara, DDS

Dr. Rodrigo Guevara graduated from the University of Maryland School of Dentistry and is a licensed dentist in Virginia and Washington, DC. Born in Peru, he is fluent in Spanish and enjoys seeing patients from different cultural backgrounds. Dr. Guevara has experience as a general dentist in both non-profit and private practice clinics. He enjoys staying active in his free time, playing basketball and soccer.


Sandra Kim, DMD

Dentist Sandra Kim graduated from the Pennsylvania School of Dental Medicine and completed her residency at the Hospital of the University of Pennsylvania. Her experience in Philadelphia included teaching dental students and working as a general dentist in a private practice. Dr. Kim also has provided free dental services to the needy during mission trips abroad in Ecuador, Romania, Korea, Haiti and Kenya. She moved from South Korea to the U.S twelve years ago and has been a member of Mary's Center team since February 2012. Dr. Kim currently sees her patients at the Mary's Center site on Georgia Avenue in Petworth, D.C. She speaks English and Korean, along with a limited amount of Spanish. In her free time, she enjoys serving special needs friends in her church ministry and going on mission trips.


Dr. Erica Lo, dentistErica Lo, DMD

Dr. Erica Lo graduated from Bryn Mawr College with honors where she earned her Bachelor of Arts in Chemistry. She worked as a Philadelphia high school teacher before deciding to combine her love of science with serving people by becoming a dentist. Dr. Lo received her Doctor of Dental Medicine from Temple University and is licensed in both Washington, D.C. and Maryland. She is excited to be a part of the team at Mary’s Center. In her free time she enjoys museums, trying new restaurants, and watching cooking shows.


Divesh Mistry, DMD, MBS

Dentist Divesh Mistry has been a member of the Mary's Center Team since October 2013. He graduated from Temple Kornberg School of Dentistry and sees his patients at the Mary's Center site on Georgia Avenue in Petworth, D.C. In his free time, Dr. Mistry enjoys playing video games, hanging out with friends, and watching sports.

Dr. Mistry says: The reason why I chose to work at the Mary's Center is because (here) the patient can receive care in multiple ways. Not only can the patients have their dental needs taken care of, but they can get their medical and educational needs satisfied, as well. The Mary's Center is all about caring for the patient and I really appreciate that.

Thamar Petit, DMD

Dr .Thamar Petit graduated from Temple Kornberg School of Dentistry in 2013 and is licensed in D.C. and MD. While in dental school she was a recipient of the Maurice H. Kornberg Dental School Scholarship and served as the Student National Dental Association (SNDA) president. She is currently a member the American Dental Association (ADA) and Academy of General Dentists (AGD). At Mary’s Center, she sees her patients at the Georgia Avenue site in Petworth, D.C. In her free time, Dr. Petit enjoys taking continuing education courses, reading thrillers, cooking, biking, traveling, badminton and basketball.

Dr. Petit says: "I chose to work at Mary's Center because it's like one big family. The atmosphere is comfortable, happy and open. The patients receive the best care in an environment where the staff genuinely cares."

Joseph Rizk, DMD

Dentist Dr. Joseph Rizk sees participants at Mary's Center's site on Georgia Avenue in Petworth, D.C. and on Mary's Center's mobile pediatric dentistry unit. He completed his dentistry degree at Temple Dental School. Dr. Rizk joined the Mary's Center team in October 2012 and enjoys traveling and playing sports in his free time.

Dr. Rizk says: "Having grown up outside of Detroit, I chose to work at Mary's Center to help out underserved communities. I love bringing a relaxed and pleasant experience to every patient I see."



Ava Selya, DMD

Dr. Ava Selya joined Mary’s Center team in October 2015. After graduating from Temple University’s Kornberg School of Dentistry, she worked in a pediatric dental office in Pennsylvania, where she gained valuable experience in treating pediatric and special needs patients. Dr. Selya was drawn to Mary’s Center by the staff’s emphasis on helping each and every patient that walks through the door. She describes her Mary’s Center colleagues as “incredibly kind and caring”, and she is pleased to contribute to the success of the Dental team. Dr. Selya enjoys traveling, reading, and spending time with friends and family.


Dr. Derejew TessemaDerejew Tessema, DDS

Dr. Derejew Tessema joined Mary’s Center in September 2016. However, his relationship to Mary’s Center dates back to 2006, when he and his family used to receive care at the Center. Now, he serves his patients with the same care, respect and love he received. Dr. Tessema is from Ethiopia and speaks English and Amharic, which helps him eliminate access barriers for the larger Ethiopian diaspora around DC. He enjoys working with the diverse patient population at Mary’s Center. He initially graduated with an architecture degree from Addis Ababa University and a postgraduate diploma in project management from Wits University in South Africa and practiced as an architect and engineer for about 13 years. He then decided to become a dentist and graduated with a biology degree from the University of the District of Columbia and a Doctor of Dental Surgery degree from the University of Maryland School of Dentistry in Baltimore. He was the recipient of the Dr. Henry S. Hohouser Memorial Scholarship and the Champion of Excellence Award at UMB. He also received the American Academy of Oral and Maxillofacial Radiology Award and the American Association of Oral and Maxillofacial Surgeons Dental Implant Student Award.


Dr. Jessica Yoo, dentistJessica Yoo, DMD

Dr. Jessica Yoo graduated from Temple University’s Kornberg School of Dentistry. While in school, she provided high-quality dental care to patients in Pennsylvania and remote villages in Haiti. Dr. Yoo joined Mary’s Center in 2017 and is a licensed dentist in Virginia, Maryland, and Washington, DC. She is equally fluent in both English and Korean. She loves to dance, whether it’s waltz, kpop, swing, or jazz, and spend time with friends and family, which includes a menacing pup and an older dog that gets fed up with the menacing pup.


Dental Hygienists

Ayesha AhmadAyesha Ahmad

Ayesha Ahmad graduated with her Bachelors in Public Health from George Mason University in 2014 and later received her degree in Dental Hygiene from Howard University College of Dentistry in 2017. She joined Mary’s Center shortly after graduating and currently practices at the Fort Totten site. Ayesha is passionate about public health and strives to provide quality care and oral hygiene education to each of her patients. On the weekends, Ayesha can be found at local farmers markets, spending time outdoors or baking cakes for her small side business. She’s also a huge Toronto Raptors fan.



Tiffany ColonTiffany Colon

Tiffany Colon obtained a  degree in Computer Information Systems from Pace University, but later decided to pursue a career in oral health. She graduated from New York University with a Bachelor of Science degree in Dental Hygiene. Her professors praised her for her determination, her commitment to increasing access to dental care and her ability to relate well to patients. During her studies, Ms. Colon volunteered for many outreach programs, including to Puebla, Mexico. Originally from Brooklyn, NY, she has also had the opportunity to travel the world with her military parents. In her spare time Ms. Colon enjoys traveling and spending time with her son. Her goal as a hygienist is to ensure the best care for all her patients.


Carla C. Cornejo, RDH

Dental hygienist Carla C. Cornejo graduated from dentistry school at Universidad Automoma Juan Misael Saracho in Bolivia and completed the Dental Hygiene Program at Northern Virginia Community College. Ms. Cornejo has her CPR and BLS certification and is fluent in Spanish and English. She sees her patients at the Mary's Center site on Georgia Avenue in Petworth, D.C. Ms. Cornejo has been a member of the Mary's Center team since February 2011. In her free time, she enjoys riding roller coasters, cooking, hiking, camping, and doing other outdoor activities.

Ms. Cornejo says: "My goal is to provide quality dental service to the community through education and prevention."



Susan FrancosSusan Francos, RDH

Susan “Susie” Francos is a Registered Dental Hygienist in Maryland, District of Colombia, and Florida. She graduated from Miami Dade College in 2010 and has been a part of many volunteer services including Mission of Mercy and the Special Olympics. In 2011, Ms. Francos moved to Australia, where she traveled and worked as a dental assistant in Brisbane, Queensland. After that, she worked for four years as a dental hygienist with The Mobile Dentist in Silver Spring, MD, gaining experience in working with special needs and geriatric patients, among others. Ms. Franco also served as the hygienist to the veterans at the Armed Forces Retirement Home of D.C. When she's not fixing smiles, Susie spends her time exploring new places. She also teaches yoga. 


Jillian HartmanJillian Hartman, RDH, BSDH

Jillian Hartman, a Registered Dental Hygienist in Pennsylvania and Washington, DC, joined Mary's Center at the Fort Totten location in July 2017. A 2016 graduate of West Virginia University's School of Dentistry with a Bachelor of Science degree in Dental Hygiene, Ms. Hartman has her certification in BLS (Basic Life Support) and CPR (Cardiopulmonary Resuscitation), and is board certified to administer local anesthesia and nitrous oxide. A native of York, Pennsylvania, she worked in private practice in the Keystone State's state capital, Harrisburg, for one year before relocating to our nation's capital to pursue her passion for engaging with and providing comprehensive oral health care to our diverse community. In her free time, she enjoys exploring the city with her Bichon-A-Ranian puppy, Remy.


Faiza Ismail

Dental Hygienist Faiza Ismail, an alumna of Howard University, has been a member of the Mary's Center team since January 2010. Ms. Ismail has been practicing Dental Hygiene for thirteen years and has her CPR certification as well as a Dental Hygiene License for Maryland, Virginia and the District of Washington. She speaks Somali and English and is also studying Spanish. In her free time, Ms. Ismail enjoys exploring the outdoors, practicing Bikram Yoga and spending time with family and friends.

Ms. Ismail says: "I absolutely enjoy being a hygienist. I look forward to [treating and educating] my patients on the importance of maintain oral health and overall well-being. I'm so proud of how Mary's Center [has] improved the communities around it and I feel lucky to be a part of it."

BeYonne White, RDH, BS

Dental Hygienist BeYonne M. White graduated from University of Maryland School of Dentistry's dental hygiene program in May 2013. At Maryland her passion for public health was nurtured by various community outreach programs and exposure to special patient populations. Before joining the Mary's Center team in October of 2013, Ms. White worked for the Center for Investigative Diseases, Management and Research dental clinic at Howard University where she treated patients living with HIV. The experience taught her a lot about public health, grants and allowed her many unique experiences. Ms. White has her CPR and BLS certification and is board certified to administer local anesthesia. She sees her patients at Mary's Center's site on Georgia Avenue in Petworth, D.C. In her free time, she enjoys traveling, making jewelry, home improvement projects and researching anything and everything.

Ms. White says: "I researched Mary's Center in 2011 hoping to simply volunteer, however being a full time employee and part of a wonderful group of people feels amazing."


Education - This is a contributing Drupal Theme
Design by WeebPal.