Welcome to Redondo Oral Surgery! Our oral surgeons and team make it their mission to provide the highest standard of personalized oral surgery in a caring and compassionate environment. Our goal is to create a calming atmosphere, and to provide you with exceptional service. We stay at the forefront of oral and maxillofacial surgery through continuing education courses, and we use the latest treatment techniques and technologies available to ensure excellent care. We invite you to call us at 310-375-0514 or visit us today to schedule your consultation with Dr. Barry Johnsin, Dr. Trent Westernoff, or Dr. Martin Mardirosian and to learn more about oral and maxillofacial surgery in Redondo Beach, California. We look forward to meeting you!

Barry Johnsin

Barry Johnsin, DDS

Dr. Barry Johnsin graduated from Penn State University summa cum laude with a bachelor’s degree in Biology. He graduated from Temple University School of Dentistry, which is a traditional four-year program, in the top 10% of his class in three years. He completed his oral and maxillofacial surgeon residency at the Los Angeles County Medical Center.

After graduating from dental school, and prior to the starting his oral and maxillofacial residency, Dr. Johnsin taught at the Temple University School of Dentistry Oral Diagnostic Department. He has also taught at the University of Southern California Dental School.

Dr. Johnsin has received the following honors: Temple University School of Dentistry Oral Surgery Honor Society and Temple University School of Dentistry Stomatognathic Society. Dr. Johnsin has been in private practice at the same location in Redondo Beach since 1977. He is currently on staff at Torrance Memorial Medical Center and Little Company of Mary Hospital. Dr. Johnsin’s special interests are outpatient general anesthesia and dental implants.

He has held the following positions:

  • Program Chairman – Western Los Angeles Dental Society
  • Secretary, Treasurer – Western Los Angeles Dental Society
  • Vice President – Western Los Angeles Dental Society

Trent Westernoff

Trent Westernoff, DMD, MD

Dr. Trent Westernoff is a board-certified oral and maxillofacial surgeon with seven years of extensive surgical experience. He graduated with honors when he received his bachelor’s degree at the University of California, Santa Barbara in 1994. In 1998, Dr. Westernoff completed his post-graduate degree, obtaining a doctorate in Dental Medicine at the Harvard School of Dental Medicine, with cum laude honors. During dental school, he became a US Army reservist and was commissioned as a captain on the USS Constitution.

Wanting to pursue a profession in oral and maxillofacial surgery, Dr. Westernoff continued his education at the University of California, San Francisco (UCSF) residency program and the UCSF School of Medicine. During his six years at UCSF, he completed oral maxillofacial surgery training, obtained his medical degree (MD) and finished a year of general surgery training. In addition to his extensive education, Dr. Westernoff was activated and promoted to the rank of major in the US Army where he served for three years as full-time hospital staff at William Beaumont Army Medical Center. While there, he practiced full-scope oral and maxillofacial surgery. He was deployed in 2005 during Operation Iraqi Freedom and served at a Combat Support Hospital in Mosul, Iraq. Dr. Westernoff received a Meritorious Service Medal for his outstanding service while in Iraq.

Dr. Westernoff completed board certification for both the American Board of Oral and Maxillofacial Surgery and National Dental Board of Anesthesiology, and he currently holds diplomate status in both organizations.

After completing nine years in the US Army Ready Reserve and three years of active duty, Dr. Westernoff and his wife elected to move back home to Southern California, where they are raising their family and continuing their professional careers.

Awards and Honors:

  • 2014-15: Board Member South Bay Children’s Health Center
  • 2013-14: Board Member South Bay Children’s Health Center
  • 2014: Immediate Past President Western Los Angeles Dental society (WLADS)
  • 2012-14: Board Member Dental foundation of California
  • 2012: President West Los Angeles Dental Society
  • 2012: Treasurer West Los Angeles Dental Society
  • 2011: Secretary West Los Angeles Dental Society
  • 2009: Editor West Los Angeles Dental Society
  • 2008-09: Local Area Representative West Los Angeles Dental Society
  • 2008: Who’s Who in America
  • 2007: Army Commendation Medal, Ft. Bliss Dentac, US Army.
  • 2005: Meritorious Unit Commendation, 228th Combat Support Hospital, Iraq, US Army.
  • 2005: Meritorious Service Medal, 228th Combat Support Hospital, Iraq, US Army.
  • 2005: Order of the Combat Spur, 11th U.S. Calvary Regiment, US Army.
  • 1998: Graduated cum laude, Harvard School of Dental Medicine.
  • 1998: Oral Biology Award, The American Association of Oral Biologists.
  • 1998: Award for Excellence in Research, The Harvard Odontologic Society
  • 1998: Hatton Award Finalist, International Association of Dental Research.
  • 1997: American Association for Dental Research Student Research Fellowship.
  • 1995-1998: U S Army Health Professions Scholarship Program.
  • 1994: Graduated Honors, College of Letters and Science, University of California, Santa Barbara.
  • 1993: Certificate of Achievement, Order of Omega Honor Society.
  • 1993: Sigma Chi Foundation Student Scholarship Award.
  • 1992: Dean’s List Scholars Award.
  • 1992: Golden Key National Honor Society.
  • 1991: Dean’s List Scholars Award.
  • 1991: Alpha Lambda Delta Honor Society.

Martin Mardirosian

Martin Mardirosian, DDS, MS, MD

Education and Training

Southern California native Martin Mardirosian graduated from the University of California, Los Angeles with a bachelor’s degree in Biology. He earned his Master of Science in Oral Biology & Medicine, as well as his Doctor of Dental Surgery (DDS) degree from the UCLA School of Dentistry, all while on the Dean’s Honor List. He then went on to earn his Doctor of Medicine (MD) degree at the UCLA School of Medicine and completed his residency in Oral & Maxillofacial Surgery at the UCLA School of Dentistry, along with a year of general surgery residency at the Ronald Reagan UCLA Medical Center.

Oral Surgery Interests
Full scope oral surgery; with extensive training in implant surgery and implant dentistry, bone grafting and reconstructive surgery, benign and malignant pathology, dentoalveolar surgery, trauma surgery, ambulatory anesthesia, and clef lip and palate surgery.

Dr. Mardirosian is affiliated with the following professional organizations:



  • General Anesthesia Sedation Permit
  • Basic Life Support (BLS)
  • Advanced Cardiac Life Support (ACLS)
  • Pediatric Advanced Life Support (PALS)
  • Advanced Trauma Life Support (ATLS)
Activities & Community Service

  • May 2010-Present: Thousand Smiles Foundation – Maxillofacial Deformities
  • July 2013-Present: Bank of Hope Community Outreach
  • July 2010-Prsent: Academy of Osseointegration’s Young Clinician’s Committee
  • September 2007-Present: Armenian Graduate Student Association Mentorship Volunteer
  • September2007-Present: American Student Dental Association
  • September 2007-June 2011: Hispanic Dental Association
  • November 2007-June 2011: Class of 2011 Oral Surgical Track Coordinator
  • January 2005-March 2007: Pre-Dental Student Outreach Program
  • March 2007-March2007: Sigma Alpha Epsilon Fraternity, Committee Member
  • September 2004-March 2007: Armenian Students Association, Social & Publicity Committee

Awards & Honors

  • 2010: Student Grant Award – American Academy of Implant Dentistry
  • 2010: Best Oral Scientific Research Presentation – Academy of Osseointegration
  • 2010: Dean’s Honor List – UCLA

Martin and his wife, Sharis, have been happily married since 2014 and recently welcomed their son, Leo, in April of 2017. In his spare time, Dr. Mardirosian enjoys working with computers, snowboarding, cycling, cooking, and running with Teddy — the Mardirosian family’s Golden Retriever.