Sonia R. Mendez, DDS

Dr. Mendez received her degree in dental surgery at UCSF in 2004. She worked for 10 years in San Francisco before taking over the practice of Dr. Dean DeRanieri in 2014. She strives to continue to provide excellent dental care to the residents of South San Francisco and its surrounding areas. Being a true believer in lifelong learning, her knowledge of dentistry is kept up-to-date with continuing education courses on a variety of subjects, including implants, cosmetic dentistry, and much more. She is an active member of the American Dental Association, the California Dental Association, and the San Mateo Dental Society. Her commitment to patient comfort and satisfaction ensures that every patient that comes into her care is treated with respect, kindness, patience, and a gentle touch. In her free time, she enjoys cooking, reading, and spending time with her two daughters. In addition, she volunteers at a clinic in San Mateo, providing free dental care to people in need.



Judith Reece, Da

Our longest standing staff member, Judy, is a dental assistant who has been with the practice since 2000. She is semi-retired, and now only comes in every other Monday to confirm patients and answer phone calls. She enjoys baking and taking care of plants with her green thumb.



Esme has been the office manager at this practice since 2002. The part of her job that she finds most rewarding is getting to know people and developing relationships with patients over the years. Hers is the friendly face that greets patients as they walk through the door. She enjoys spending time with her family, and hanging out with her boys in her free time.


Nancy Gonzalez, RDA

Nancy is a Registered Dental Assistant and has been working in this dental practice since 2001. She likes her job because no day is the same in her line of work. Patient care and procedure knowledge are on top of her list for helping patients feel comfortable in the dental office. Family time and keeping her kids busy in activities is what she loves to do in her free time.


Kathleen Hartford, RDH

Kathleen obtained her dental degree (Registered Dental Hygienist) from Foothill College in 2010. Her love for clean teeth developed early because she grew up around the dental field with her mom managing a dental office. She enjoys cooking, hiking, reading, and spending time with her loved ones, including her husband and pup, Jameson.

Sonia is a fantastic dentist! I’ve been seeing her for years and appreciate her wonderful personality and top-notch skills — I highly recommend her and her practice.
— Jenny Oh, Producer at KQED