Meet Our Team


Maria G

Registered Dental Hygienist

My name is Maria. I was born and raised in San Juan, Puerto Rico. I moved to California at age 14 and attended high school in Livermore and college in Hayward, California. I attended the Chabot College dental hygiene program and graduated with honors in 1991.

I have been a Registered Dental Hygienist for over 25 years and I am current on all my license requirements. I also attend continuing education courses on an ongoing basis. I love my profession and my patients affirm my passion for my work. I provide thorough gentle hygiene care with comprehensive patient education to enable patients to maintain optimum oral hygiene.

I am married and have two children. We enjoy traveling, sightseeing and sports. During my spare time, I enjoy reading and exercising.



Kathy M

Registered Dental Assistant

My name is Kathy. I've been in dentistry for over 20 years. My goal is to take excellent care of patients during their time with me. Outside of work, I can be found spending time with my family, traveling, fun outdoor activities and savoring delicious food at some of my favorite restaurants. I am happily married and have 3 wonderful children.



Esther L

Office Administrator

Hello, my name is Esther. I am Dr. Ko's Office Administrator. As your insurance and billing specialist, I am here to assist you through explaining and discussing your insurance benefits and processing dental claims. i enjoy working with you on the financial aspects of your dental needs. I am privileged to be part of his wonderful team. We all work extremely well together to provide the best service for you. Our staff is very warm and caring. I love the positive energy felt by everyone and I appreciate the attentive care Dr. Ko and the team strive to provide, as individuals and collectively, to each patient.

I am the youngest of 16 children in my family. I love outdoor activities, especially gardening. In my spare time, I enjoy spending quality time with my grandchildren.


John H Ko, DDS
5720 Stoneridge Mall Rd, Suite 200
Pleasanton, CA 94588
Phone: 925-847-8790
Fax: 925-847-0728
Office Hours

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