The Team

Dr. Nathan Christensen is an advocate of biomimetic dentistry (minimally invasive dentistry preserving maximum natural tooth structure) and has done extensive post- graduate work at UCLA in root canal treatment. His memberships include the American Dental Association, California Dental Association, Academy of General Dentistry and Academy of LDS Dentists.

Dr. Nathan Christensen graduated from the Hermam Ostrow School of Dentistry at USC in 2012. During his educational period he achieved and partook in many activities, including serving as the USC Student Chapter President from 2010 to 2011 and making the Dean’s list Summer 2009, Fall 2010 and Spring, Summer and Fall 2011.

Dr. Nathan Christensen volunteers service at monthly clinics. He also volunteered at the International Clinic in Belize in April of 2011. For this, he was given a humanitarian award for service to the children of Southern California and Belize.


Dr. Nathan Christensen is a member of several local and national dental organizations including:

  • American Dental Association
  • California Dental Association
  • American Academy of Cosmetic Dentistry
  • Academy of General Dentistry
  • Academy of LDS Dentists


Hemant Sachdeva, DDS, brings extensive experience in preventive and cosmetic dentistry to Rancho San Diego Dental Group in El Cajon, California.

Dr. Sachdeva was born and raised in central California. He earned his undergraduate degree from UC Berkeley and obtained his Doctor of Dental Surgery from the Herman Ostrow School of Dentistry of the University of Southern California. At USC, doctor Sachdeva also earned the Thor Award for providing outstanding service to handicapped and disadvantaged patients.

Outside of the office, Dr. Sachdeva loves using his dentistry skills to provide humanitarian service. During the course of his career, he’s traveled as far as Cambodia to provide dental service for those in need. He’s also worked with veteran and homeless populations throughout California to promote preventive oral health care and improved hygiene.

Dr. Sachdeva is fluent in English, Spanish, Punjabi, and Hindi. When he isn’t working with patients, Dr. Sachdeva enjoys hiking, camping, and playing sports such as tennis, racquetball, and golf. He welcomes any patient seeking comprehensive oral health care to Rancho San Diego Dental Group.

Dr. Wai “Jack” Chan is a compassionate and caring pediatric dentist, whose calm demeanor has a soothing effect on children.  He loves pediatric dentistry because it gives him a chance to interact with kids and make a difference in their oral and overall health.


Dr. Jack was born in Hong Kong and immigrated to the US when he was nine years old. He spent the rest of his childhood in the picturesque adirondacks of upstate New york. After growing up and training in colder climates, he is happy to be establishing roots in sunny San Diego!


Dr. Jack attended Cornell University, where he completed his Bachelor's degree in Biological Sciences. He then received his Doctorate of Dental Surgery at SUNY Stony Brook School of Dental Medicine where he not only got training in pediatric dentistry, but also training in treating patients with special needs. After graduating from dental school, he went on to complete a year of general practice residency at SUNY Stony Brook School of Dental Medicine, where he received additional training on complex restoration for adult population and in depth focus on the special needs population. He then practiced as a general dentist at a federally qualified health center in upstate New York to help deliver care to low income individuals and   discovered his passion for pediatric dentistry. Following the stint as a general dentist, he continued to seek further education in pediatric dentistry at University of Minnesota, where he got additional training in treating the pediatric population and kids with special health care needs. He has since worked as a pediatric dentist in California.


Dr. Jack believes in creating individualized care for each child and their family. Having worked as a general dentist, he has seen the detrimental effects of a lack of education and lack of prevention have on teeth. This effect can often carry on into adulthood and have permanent effects on adult teeth. He focuses on creating a positive experience and helping to build self-esteem in a dental setting while encouraging healthy oral habits.


Dr. Jack is excited to be working with the team at San Diego Children’s Dentistry and Rancho San Diego Dental Group!  When he isn’t practicing dentistry, he enjoys being outdoors or recreating recipes he's tried in restaurants.

Thomas V. Brislin Jr., the youngest of six children, grew up in Harveys Lake, Pennsylvania. He’s a natural athlete and enjoyed competing in soccer, volleyball and is an avid water sports enthusiast. Tom was a Varsity Soccer player while he attended Saint Joseph’s University during his undergraduate studies and graduated with a Bachelor’s Degree in Accounting. “Crunching numbers,” Tom realized, was not his real passion. He decided to pursue Dentistry and in 2011, he graduated from Temple University School of Dentistry in Philadelphia, Pennsylvania.


After Dental School, Tom was commissioned as a General Dental Officer in the United States Navy and was stationed at Camp Pendleton, California. In 2013, Lieutenant Brislin was part of Pacific Angel Vietnam, a multi-service Medical and Dental Humanitarian Mission in Vietnam. Tom was Honorably discharged from the US Navy and completed his Oral Maxillofacial Surgery residency training at Temple University Hospital in Philadelphia, Pennsylvania. It was during his residency training that he realized his great interest in the pathology of the head and neck, implant restorations of missing teeth and advanced sedation techniques.


Tom and his wife, Kirby, have five children. The family returned to Southern California to enjoy the sand, sun, and surf. When he’s not busy transforming smiles with his oral surgery skills, he is spending time with his family at the beach, camping, running or golfing.

Dr. Jeff Takai, is a dental implant and gum disease specialist at Rancho San Diego Dental Group. Dr. Takai grew up in southern California where his father was also a dentist. As a result, he has been involved in dentistry in some capacity his entire life and he developed a strong passion for dentistry at a young age.

Dr. Takai completed his undergraduate schooling at UC Berkeley. He then attended University of the Pacific for dental school and earned his Doctorate of Dental Surgery. While in dental school Dr. Takai was attracted to the surgical side of dentistry and decided he wanted to become more specialized. Upon graduation, he furthered his education and training in periodontics at UC San Francisco where he completed his surgical residency in 2013.

Dr Takai is a member of the following organizations:

  • Academy of Osseointegration
  • American Academy of Periodontology
  • California Society of Periodontology
  • American Dental Association
  • California Dental Association

Dr. Takai and his wife, Sarah live in southern California where they enjoy cooking and traveling together. During his free time, Dr. Takai also enjoys reading, practicing Jiu Jitsu and playing golf.

Dr. Patricia Campillo obtained her doctor in dental medicine degree from Temple University in Philadelphia, where she graduated Summa Cum Laude. In 2014 she was inducted to the Omicron Kappa Upsilon Kappa Kappa Chapter, a national dental honor society.‍

She continued her training at Temple University where she received her certificate in Orthodontics and Masters degree in Oral Biology in 2016. She is a member of the American Dental Association, California Dental Association and the American Association of Orthodontists.

Dr. Patricia is committed to providing quality and orthodontic care to her patients in a comfortable and welcoming environment. In her free time, Dr. Patricia enjoys spending time with her family, baking and traveling.

Dr. Mark Karpman is the in-house endodontist at Rancho San Diego Dental Group.  Dr. Karpman is a highly trained and compassionate endodontist with over 30 years of experience.  He has remained at the top of his field by completing extensive continuing education studies throughout his career.  He truly cares about his patients, and approaches each patient's treatment plan with an unbiased approach.  Dr. Karpman is committed to providing excellence in endodontic service in a professional, caring and comfortable atmosphere, and is an integral part of the team at Rancho San Diego Dental Group.  Dr. Karpman is married with children and enjoys spending his free time playing outside with them!