About Us | Sierra Dental Group - Dentist Fontana, CA 92337 | (909) 327-4308

AboutSierra Dental Group

Sierra Dental Group is a Fontana based family dentist practice that treats patients of all ages. We are committed to delivering the highest quality dental care and do so using advanced dental equipment. We are a cosmetic dentist that offers services like checkups, teeth cleaning, crowns, veneers and more.

We also perform emergency dentist services that include bonding, root canals, crowns, and bridges. As a local dentist, we create lifelong relationships with our patients and their families and work to ensure that they receive treatments in a comfortable and relaxed environment. Dr. Ra and our team invite you to schedule an appointment by calling 909-327-4308 and experience why our patients think Sierra Dental Group is the best dentist in Fontana.



Dr. Phil J. Ra was raised in Southern California and currently takes pride in residing and practicing the art and science of dentistry in Upland and the surrounding areas. His childhood goal of becoming a dentist became a reality when he was accepted into the prestigious six-year Accelerated Dental Acceptance Program Tract (ADAPT) at the University of Southern California School of Dentistry right out of high school in 1994. Dr. Ra is proud of this accomplishment, as only a select group of students in the nation are accepted into this academically rigorous and clinically grueling accelerated program.

After becoming one of the youngest doctors to graduate with a Doctor of Dental Surgery degree in the history of USC in 2000, Dr. Ra spent several years (and still spends many hours) attaining up-to-date continuing dental education and training to better serve the Inland Empire for over 15 years. . His unwavering commitment to staying on top of dentistry's latest techniques and research has earned him the highly prestigious Fellowship from the Academy of General Dentistry. This means he has the skills gained from more post-doctorate education in 3 years than the State of California requires dentists to take in 20 years of practice.

In 2007, Dr. Ra received the "Top Dentists in America" award, given annually by the Consumer Research Council to selected dental healthcare professionals. Starting in 2008, Dr. Ra was extremely honored to be voted as one of the "FAVORITE DENTIST OF THE INLAND EMPIRE" by the Inland Empire Magazine for 7 years straight.

Currently, Dr. Phil J. Ra is a member of the ADA, AGD, IAOMT, and the ICOI and has a FELLOWSHIP in the Academy of General Dentistry (AGD) and FELLOWSHIP in the International Congress of Oral Implantology (ICOI) and also an Associate Fellow from the World Clinical Laser Institute (WCLI). Dr. Ra is one of the very select few in the Inland Empire to be certified in the LANAP (Laser Assisted New Attachment Protocol) and was one of the first doctors to be trained in the pinhole gum rejuvenation procedure. He is also actively involved in organized dentistry, previously serving as a board member in the Southern California Academy of General Dentistry. Dr. Ra was a regular contributor to dental health articles for the Inland Empire Family Magazine and is also a manuscript peer-reviewer for the General Dentistry magazine, which is the leading peer reviewed publication for the general dentist. He is also involved in numerous study clubs in order to maintain the latest knowledge in cutting edge dentistry.

Dr. Ra practices Biologic Dentistry and maximizes the power of cavity re-mineralization, alkalization of the mouth, and other homeopathic and minimally invasive techniques to help every patient be as healthy as possible.

In our Upland dental office, patients have the opportunity to complete dental material compatibility testing. This test will inform your dentist of any reactivity within your body to specific dental materials. Dr. Ra only uses the most biocompatible materials.

Our office uses the latest in digital dental radiographs, digital 3D radiographs (CBCT), digital photography, and polarized infrared light (diagnocam technology) to offer the safest and most accurate diagnosis. We also employ CEREC (CAD/CAM Technology) which allows us to perform same day permanent conservative biocompatible restorations. This is convenient for our many patients who travel in from out of the area for treatment.

The 3D (CBCT) is a wonderful technology employed to evaluate root-canalled teeth for cracks and chronic infections that potentially leak pathogenic bacteria into your body. When needed, this technology is used to perform simple guided flap-less implant surgery. This is the least traumatic and least painful implant procedure.

Another great advantage to Dr. Phil Ra's SmileStudio is his "in-house" dental laboratory. When aesthetic services are needed or desired, no work is out-sourced from the office. Our in house lab allows perfect communication of patients' desired outcomes to the ceramist fabricating the crown or veneer. We perform custom smile design, custom shade matching, and in house quality control using the highest quality ceramics in existence. Whether it is one tooth in the front of the mouth or your entire smile, our in-house laboratory ensures your aesthetic desires are met and exceeded.

Chris Yoo, DMD – General Dentist

Dr. Christopher Yoo was born and raised in Southern California. He received his Bachelor Degree in Economics from the University of California, Irvine. He then moved to Boston, MA where he received his Doctor of Dental Medicine degree from Tufts University School of Dental Medicine. After graduating, Dr. Yoo has moved back to Southern California where he is now practicing dentistry full time.

In his spare time, Dr. Yoo enjoys playing a variety of sports (basketball and tennis, mostly), watching movies, and exploring new places to eat.

Roy Yoo, DMD – Periodontist Specialist / Gum Specialist

Dr. Roy Yoo spent most of his childhood years in the South Bay area before he moved to the Bay area to attend college. He graduated from UC Berkeley with a major in Molecular & Cell Biology. After graduating from UC Berkeley, Dr. Yoo moved to Boston where he attended the Harvard School of Dental Medicine.

Dr. Yoo received his Doctor of Dental Medicine degree from Harvard in 2004. After finishing dental school, Dr. Yoo moved back to Southern California and continued his specialty training in periodontics at the USC School of Dentistry. During his training, Dr. Yoo has done extensive research and has published articles in The International Journal of Oral & Maxillofacial Implants and The Journal of the Western Society of Periodontology.

As a Board Eligible Periodontist, Dr. Yoo limits his clinical practice to periodontics & implant dentistry. He is qualified in all areas of periodontics and has extensive clinical experience with most major implant systems. Dr. Yoo is dedicated to serving his community with the highest quality of care and stays updated with the latest developments in his specialty. Dr. Yoo continues to be actively involved in his community. He remains affiliated with the USC Advanced Periodontics Department as a part-time faculty member and his professional affiliations include memberships to the American Academy of Periodontology, Academy of Osseointegration, California Society of Periodontists, Western Society of Periodontology, South Coast Periodontal Group, Interdisciplinary Dentofacial Institute, California Dental Association, and the American Dental Association. He currently works in our office once a month.

Dr. Garrett Dacker, DDS, MDS – Orthodontist

Meet Dr. Garrett. He is an orthodontic specialist and a SoCal native from Glendora. He graduated from the prestigious NYU College of Dentistry at the top of his class and was inducted into the Omicron Kappa Upsilon national dental honor society. Dr. Garrett then attended Rutgers School of Dental Medicine where he received his Masters in Dental Science and Certificate in Orthodontics. He’s ecstatic to be back home in sunny SoCal creating beautiful smiles for his home community.

His passion is to help you achieve your best smile. Every patient’s treatment is a unique puzzle but the end goal is always a smile filled with self-confidence. Dr. Garrett and his team can’t wait to meet you and work hard for you on your journey to straight teeth.

Dr. Jon Hoang, DDS

Dr. Jon has been involved in the field of dentistry since high school. His passion led him to completing his Doctor of Dental Surgery degree at UCLA. He is a firm believer in providing honest and quality dentistry to all patients. His patience and compassion allow him to see patients of all ages.

Dr. Jon’s goal is to help patients get the smile they desire while helping them feel more comfortable and lessening their fears of dentistry.