Private Orthodontic Practice of Nguyen, Katsura, Loos, Moutsatson. Tradition, Quality, Care Established 1966

Nguyen, Katsura, Loos, and Moutsatson. Practice Limited to Orthodontics

Staff Photo with a patient who just got braces. He's happy.

Practice Limited to Orthodontics

Orthodontic Specialists. We are a private orthodontic office located in Long Beach. We do one thing only: Braces. Our training, experience, and facility are all dedicated to orthodontics. We offer traditional metal brackets and ceramic brackets. Invisible braces and removable appliances are utilized when feasible.

Positioning brackets using special positioning guide.

Hands-On. The doctor is always there, supervising and executing every step.

Old School. We have no problem forming wires from scratch and making intricate adjustments to the wire to create a truly unique, beautiful smile.

Twin just got their braces off.

Our Mission. We strive to deliver quality orthodontic care at a reasonable fee in a personable, enjoyable environment. Our goal is your satisfaction, not just during treatment, but years later. We want to be remembered for the quality of the work we did, as well as the care that was given.

Cephalometric analysis.


Please welcome Dr. Thao V Nguyen to our practice. She graduated from USC with honors, and is a Diplomate of the American Board of Orthodontics, the highest level of professional achievement in this field. She is gentle and kind, and will be bringing the latest techniques to our office.

Dr Thao V Nguyen.

Dr. Michael Katsura is a graduate of Harvard School of Dental Medicine, cum laude. He received his orthodontic training at the University of Southern California. Energetic, sociable, and good-natured, Dr. Katsura has been practicing since 1989, and at the current location since 1996.

Emblem of Harvard School of Dental Medicine.

Dr. John Moutsatson is also a graduate of the University of Southern California. Sincere and easygoing, Dr. Moutsatson has been here since 1976, along with former doctors, Dr. James Loos and Dr. Eldor Sagehorn. They are all USC graduates. We're as Trojan as it gets. Fight On!

USC's Tommy Trojan.


We are located in a professional medical/dental building with ample parking and disability access. We maintain a comfortable, open environment, both physically and figuratively. There is not much partition between the waiting area, the treatment area, and the sterilization area. Everything is done in the open. Parents and friends are welcome to join us in the treatment area, as long as the patient doesn't mind, to ask questions, observe, or just keep company.

Waiting area and the treatment area, showing the openness of our facility.

We have magazines, wireless internet, coffee, tea, hot chocolate, and juice. We get muffins and fresh fruit delivered daily.

Welcome to our practice!

Fresh flowers on the main desk.

  • No charge for consultation.
  • We accept most insurance plans. We go by the book. No games.
  • All charges and financial arrangements will be clearly laid out ahead of time. No hidden charges or other surprises.
  • Sterilization monitored weekly by Sterilizer Monitoring Service.
  • Safety procedures monitored by OSHA Compliance Partners.
  • We also speak Spanish (staff), Vietnamese (Dr N), Japanese (Dr K), and Greek (Dr M).

Instruments packaged in a sterilization bag.

Tooth brush, floss, and tooth paste.

Caring for your teeth
during orthodontic treatment

Traditional Hawley retainer and a clear retainer.