Dr. Gianmarco O'Brien, DDS

Dr. Gianmarco O'Brien, DDS

Prosthodontics  |  
Male  |  
Age 44
Dr. Gianmarco O'Brien, DDS is a prosthodontics practitioner in Orange, CA and has been practicing for 12 years. He graduated from University Of The Pacific / School Of Dentistry in 2003 and practices prosthodontics, dentistry, and more.

1140 W La Veta Ave Ste 530

Orange, CA 92868

Contact Information

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Practice Areas

  • Prosthodontics
  • Cosmetic Dentistry
  • Dentistry
  • Emergency Dentistry
  • Family Dentistry
  • Minimally Invasive Dentistry
  • Neuromuscular Dentistry
  • Orofacial Pain Dentistry
  • Reconstructive Dentistry
  • Sedation Dentistry
  • Special Care Dentistry
  • Sports Dentistry

Conditions Treated

  • Cavity
  • Chipped Tooth
  • Dental Disorders
  • Edentulism
  • Gingivitis
  • Grinding of Teeth
  • Gum Disease
  • Phobia
  • Sleep Apnea
  • Tempormandibular Joint Pain
  • TMJ
  • Tooth Abrasion
  • Tooth Abscess
  • Tooth Attrition
  • Tooth Decay
  • Tooth Demineralization
  • Tooth Discoloration
  • Tooth Loss
  • Toothache


Background Check

0 Malpractice Claims

No malpractice history found for California.

0 Sanctions

No sanctions history found for the years that Healthgrades collects data.

0 Board Actions

No board actions found for the years that Healthgrades collects data.


  • Santa Clara University
    Undergraduate School | Graduated 1996
  • University Of The Pacific / School Of Dentistry
    Medical School | Graduated 2003
  • Prosthodontics (Prosthetic Dentistry)
    Residency Hospital | Completed 2006
  • University Of California, Los Angeles. (UCLA)
    Residency Hospital | Completed 2006

Awards & Recognition

Awards & Honors

Dr. O'Brien has no awards or honors listed.

Media & Publications

Dr. O'Brien has no media or publications listed.

Languages Spoken

  • English

Memberships & Professional Affiliations

Dr. O'Brien does not have any memberships or affiliations listed. If you are Dr. O'Brien and would like to add memberships or affiliations, please update your profile.

Dr. O'Brien's Reviews

Likelihood of recommending Dr. O'Brien to family and friends
based on 34 total reviews (16 with comments)

Likelihood to Recommend (34)

  • 5
  • 4
  • 3
  • 2
  • 1

Dr. O'Brien's Performance

Explains condition(s) well
Answers Questions
Time well spent

Office & Staff Performance

Office environment
Staff friendliness
Average wait time
Under 10 minutes

Patient Comments (16)

in Upland, CA
500 characters wasn't enough to adequately describe the extraordinary expertise and attention to detail that this doctor has, so here's my continuation. If you really care about your teeth & the work being done, "and" if you really want the BEST IN CLASS, Dr. O'Brien is the DDS you must see! The...more
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in Upland, CA
Dr. O'Brien is just incredible!! A few years ago I was referred to Dr. O'Brien by another dental practitioner.I wondered, "why is my appt scheduled for such a long time?" I had gone through a similar procedure w/another dentist a couple of yrs earlier & the same procedure only took a fraction of...more
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in Santa Ana, CA
I have been a patient of Dr. O'Brien's for two years. From my first experience, I was impressed with his knowledge and enthusiasm for my difficult case. He is great to work with, and I'm pleased to have been recommended to him. His professional confidence and communication ability has always...more
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in Los Angeles, CA
Dr. O'Brien is a magnificent dentist! He is a superb technician, a skilled artist and a perfectionist. He is very gentle and makes sure that you are comfortable. I am very pleased with the work he has done for me and my family. I highly recommend him.
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Dr. O'brien is one of the best doctors I met. He is very friendly and extremely skillful in what he is doing. He will listen to you and write down the history about your teeth problems so that he would be able to come up with the wisest decision in order to treat your teeth problem. Thank you so...more
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