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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. 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)

Dr. 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

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 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, two cats – Bonnie and Clyde, their dog Abby, cycling, running, hiking, yoga, traveling and watching movies.

Novato Office Staff

Our Novato Staff

Briana Richards - Patient Care Coordinator (Novato)

Briana 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.