Meet Our Staff


Tiburon Office Staff


Dental Assistants

All of our experienced dental assistants are certified Registered Dental Assistants. They're not only trained and registered in orthodontic procedures, but they know how to make you comfortable during your treatment. After all, we want your visit – whether it’s your very first to determine if you even need orthodontic services or one of the last to remove an appliance – to be a pleasant one!


Front Desk Staff

When you come in for treatment, you’ll be greeted first by our friendly receptionists. They understand your scheduling challenges and financial concerns. Be assured that they will do their best to set appointments that are convenient for you, answer your billing and insurance concerns and diligently keep all your medical records accurate and up-to-date.


Our Doctors

Dr. Garry G. Gast, D.D.S. (Novato/Tiburon)

Dr.jpgDr. Garry Gast has been practicing orthodontics in Marin since 1978. After graduating from Redwood High School, he earned a Bachelor of Science degree from the University of Oregon and his Doctorate of Dental Surgery degree from the University of Detroit, Mercy. After practicing general dentistry in Tiburon, he attended UC San Francisco and received his Certificate in Orthodontics. He is past president of the Marin County Dental Society and served as Chairman of the Ethics Committee for 13 years. For the past decade, Dr. Gast has been an Associate Clinical Professor in the orthodontic department at the University of the Pacific, Arthur A. Dugoni School of Dentistry.

Dr. Gast is a member of the American Association of Orthodontists and the Pacific Coast Society of Orthodontics. A long-time Rotarian, he is past president of the Ignacio Rotary Club. With Rotaplast, he has treated cleft palate and cleft lip patients in Bolivia, Venezuela and Mexico.   

Dr. Gast is an avid sailor and enjoys skiing and fly-fishing. Dr. Gast is married to his wife, Lori, and they have two children. His daughter and two grandchildren live in Kauai, Hawaii. His son, a general dentist, is a graduate of the University of the Pacific, Arthur Dugoni School of Dentistry and currently lives in Chicago with his wife and son.Our Doctor

Dr. Matthew A. Nielsen, D.D.S., M.S.D. (Novato)

Dr1.jpgDr. Matthew Nielsen joined Dr. Gast in Novato in early 2015. Dr. Nielsen was born and raised in the Bay Area and is excited to be back in the area to raise his family. Dr. Nielsen attended dental school at the University of the Pacific in San Francisco and performed his orthodontic residency at the University of Colorado. He is a member of the American Association of Orthodontists and The American Dental Association, as well as the Marin County Dental Society.

He aims to provide the community of Novato with the highest quality orthodontic care in a comfortable and fun setting. He knows that gaining a beautiful smile can be a positive change and loves helping his patients achieve the smile they deserve.

When not in the office, Dr. Nielsen spends his time with his family. He and his wife, Bethany, have three boys and a girl. He loves hiking and exploring the beaches and trails of Marin with his family, as well as camping, photography and drawing.

Our Tiburon Staff

Consuelo “Connie” Hooper - Office Manager (Tiburon)

Connie-Hooper-photo.jpgConnie is a first generation San Franciscan. She graduated from Sonoma State University and received a degree in biology. She later received her Registered Dental Assistant license. She has been working for Dr. Gast for over 36 years.

She enjoys working with parents and their children undergoing treatment with joyful, successful results. The most rewarding part is to see several generations of family getting orthodontic treatment. The before and after results are so gratifying and truly makes her day complete.

Connie has three children, nine grandchildren, and five great-grandchildren. She enjoys spending her free time with her partner, Ed, and two dogs, Rocky and Buster. She is a nature docent, has taken international cooking classes, and loves to travel.

Lea Bumbesti - Patient Care Coordinator (Tiburon)

Lea-Bumbesti-photo.jpgLea joined the team in June of 2011. She has excellent customer service skills and enjoys making the patients feel at home. “I love talking with the patients and creating a bond. I want them to feel like this is more than just an orthodontic office. We are a family, and the patients are part of our family.”

Lea graduated with an art degree from the Santa Rosa Junior College and spent her last semester of school abroad in Barcelona. Outside of the office, Lea enjoys cooking vegan food and volunteering at farm animal sanctuaries. The animals and nature are inspiration for her art. Lea spends her weekends in Sonoma County with her boyfriend and cat. She loves exercising, exploring the outdoors, reading, and hanging out with family and friends.

Adele Langwell - Registered Dental Assistant (Tiburon/Novato)

Adele was raised in the quiet town of San Anselmo. She graduated from Drake High School and graduated from the College of Marin as a Registered Dental Assistant in 1985. Adele joined our team in 1987 and has enjoyed working together to create beautiful smiles. She enjoys the relaxed, friendly atmosphere the offices offer while giving excellent patient care.

Adele had the wonderful opportunity and experience of joining Dr. Gast and a group of medical professionals on a Rotaplast trip to Venezuela in 2001. They spent 15 days helping patients with cleft palates.

Marli Cooper - Registered Dental Assistant (Tiburon/Novato)

Marli-Cooper-photo.jpgMarli has been a Novato resident since 1987. She attended Rancho Elementary, Hill Middle School and Novato High School. She graduated from Southern Oregon University in Ashland, Oregon with a bachelor’s degree in health promotion. After graduating from SOU, she attended the College of Marin Registered Dental Assisting Program and got her RDA license in 2001. She has been part of the team ever since. She truly enjoys playing a part in the transformation in patients' smiles and watching their excitement when treatment is completed.

She enjoys spending her free time with her husband and two cats, Bonnie and Clyde, cycling, running, hiking, yoga, traveling, watching movies, and cooking healthy plant-based meals.

Novato Office Staff


Our Novato Staff

Kathy Boyle - Administrative Manager (Novato) & Patient Care Coordinator (Tiburon)

Kathy-Boyle-photo.jpgKathy has been with the practice for over 20 years and loves having a part in creating the next generation of beautiful smiles. “We have the most exceptional, friendly staff, and I am so proud of every one of them. It is so great to come to work and know that it is my job to take care of the families and to make them feel like they are part of our family. I want every part of their visit to be a positive one, and I honestly enjoy helping with their insurance and finances so that they can have the beautiful, confident smile they always wanted.”

Kathy and her husband, Scott, have lived in Novato since 1971 where they raised their five children. They are now enjoy being “Grammy and Grumpy” to seven grandchildren. 

Briana Richards - Patient Care Coordinator (Novato)

Briana-Richards-photo.jpgBriana was born in Marin County and raised in Novato. She attended Pleasant Valley Elementary, Sinaloa Middle School and San Marin High School. She has been working for the practice for 14 years. Her favorite thing about the office is the family dynamic between the staff, and she loves to provide excellent patient care at the front desk. “I strive on getting to know our patients and their parents and establish a friendly relationship.”

During the summer, she enjoys spending her time camping and enjoying the Russian River with her husband and 3three children. She loves to watch football, and her favorite team is the San Francisco 49ers.

Katherine “Kathy” Navarro - Registered Dental Assistant (Novato/Tiburon)

Kathy-Navarro-photo.jpgKathy was born and raised in San Rafael. She is fluent in English and Spanish. She graduated from San Rafael High School and then attended the College of Marin. She graduated from the Registered Dental Assisting Program in 2014. Kathy started coming to the office at the age of 14 for her orthodontic treatment, and she began working with our team in 2014.

When she is not working, she loves to hike with her two dogs, Butter and Bella. She also enjoys cooking and creating new recipes.

Tami Gannon - Registered Dental Assistant (Novato)

Tami-Gannon-photoTami was raised in Petaluma. She has been with the practice for 23 years. “I am blessed to work in a positive and caring atmosphere. My favorite part of my job is watching a patient come in, who is shy because of the way their teeth look, and when the treatment is complete, they have become confident and love their smile.”

In her spare time, she enjoys exploring the outdoors. She loves being close to her friends and family and hanging out with her French Bulldog, Stewie.