About Us

The Doctors at 4M Dental

With thousands of implants placed, the doctors at 4M Dental Implant Center have successfully taken on some of the most complex cases. Dr. Sean is a leader and educator in the field of dental implants – at the forefront of what’s happening in the industry – and passes his knowledge on to his associates. Through the 4M Institute (located in our Long Beach facility), Dr. Sean teaches the art and science of the All-on-X solution to dentists from around the world. His years of experience and wealth of knowledge enable us to educate our patients on their best options and what to expect.
Love Your Smile Again at 4M Dental Implants!
full mouth dental implants at 4M Dental Implant Center

Meet Our Doctors

Choosing to invest in dental implants is a big decision. There are many dentists who say they specialize in full-arch dental implants. So what makes us any different? Quite a lot, actually.

Sean Mohtashami,
DDS

Dr. Sean is a leading authority on full-mouth dental implants and is a world renowned expert in cosmetic dentistry. He truly knows how to design a beautiful and personalized smile.

Upon graduating from the USC School of Dentistry he continued his quest for knowledge and completed many specialty programs in his field. Deeply committed to education, in 2018 Dr. Sean created his own institute for learning in Long Beach, CA, and is currently teaching and mentoring doctors from around the world.

This, combined with over 20 years of practical experience, has made Dr. Mohtashami a Top 100 Implant Surgeon worldwide.

Samira Houshiar, DDS

Since earning her doctoral credentials at the University of California, Los Angeles, Dr. Samira has established herself as an artist in the dental field. Her attention to detail is what sets her apart as a leading cosmetic specialist in Southern California.

Her commitment to studying the newest advances in cosmetic and surgical dentistry places her in a select group of doctors able to address their patients’ most difficult dental concerns.

Dr. Samira practices in her own community of Newport Beach, California. Most rewarding to Dr. Sam is being there for her patients, making sure they receive the smiles they’ve always wanted.

Athena Goodarzi, DDS

Dr. Athena graduated from The University at Buffalo School of Dental Medicine, one of the top dental programs in the nation. She completed her residency at the College of Physicians & Surgeons of Columbia University, New York City.

Dr. Athena’s area of expertise is full mouth rehabilitation through the All On X Dental Implants Solution. She strives for excellence and is passionate about utilizing her research and academic teaching background to share her unique skills in full mouth rehabilitation with colleagues, whom she mentors across the nation. Dr. Athena takes pride in teaching full arch restorative concepts alongside Dr. Sean Mohtashami at 4M institute. 

Dr. Athena’s skills in blending art with function are unique, but her attention to detail and gentle approach to dentistry are what stand out the most. Dr. Athena’s ability to connect with her patients, create relationships, and design the best treatment possible makes her the perfect addition to our team.

Dr. Athena has profoundly affected the smiles and lives of many of our patients globally and would love to do that for you, too.

Philip Konopa, DDS

Dr. Phil received his doctoral degree from the University of Washington and completed his residency at the University of California, Los Angeles (UCLA). 

His skills and experience enable him to excel in full-service general and cosmetic dentistry with an emphasis on comprehensive/reconstructive procedures.

Dr. Konopa is well versed in fixed restorations & aesthetics, and helps our patients achieve a beautiful, functional smile they are proud to show the world.

Philip Konopa, DDS

Dr. Phil received his doctoral degree from the University of Washington and completed his residency at the University of California, Los Angeles (UCLA). 

His skills and experience enable him to excel in full-service general and cosmetic dentistry with an emphasis on comprehensive/reconstructive procedures.

Dr. Konopa is well versed in fixed restorations & aesthetics, and helps our patients achieve a beautiful, functional smile they are proud to show the world.

Derik Alexanians, DDS

Upon graduating from UCLA, Dr. Derik has made Southern California his home and has been practicing dentistry here for over two decades.

His comprehensive knowledge of restorative dentistry techniques such as extractions, bone and tissue grafting, implant surgery & placement through the use of oral and IV sedation, allows him to provide unparalleled care.

Dr. Derik is our Clinical Director. He will light up your day with his contagious smile and is one of the best people you’ll ever meet.

Derik Alexanians, DDS

Upon graduating from UCLA, Dr. Derik has made Southern California his home and has been practicing dentistry here for over two decades.

His comprehensive knowledge of restorative dentistry techniques such as extractions, bone and tissue grafting, implant surgery & placement through the use of oral and IV sedation, allows him to provide unparalleled care.

Dr. Derik will light up your day with his contagious smile and is one of the best people you’ll ever meet.

Audrey Lakani, DDS

A graduate of UCLA Dental School, Dr. Lakani comes to us from a family of longstanding healthcare professionals. As an avid learner, she has completed several residency programs in cosmetic dentistry, implant restorations, laser, and full arch dentistry.

She believes that everyone deserves a beautiful smile. As a cosmetic dentist, she treats every patient uniquely with a personalized plan of care by using modern techniques combined with the artistic aspect of dentistry to fit every patient’s needs.

We are grateful for Dr. Lakani’s talent and skill, as she is one of the most caring and knowledgeable dentists anywhere!

Kostika Polena, DDS

“I believe everyone deserves the benefit of a happy and healthy smile. As your dental provider, I am committed to helping you overcome any barriers preventing you from receiving the best oral health care possible.”

Early on Dr. Polena discovered a love and talent for art and later for science, graduating from UNLV with a degree in Biochemistry. Dentistry has turned out to be an ideal blend of his two passions. For Dr. Polena, dentistry has been a tremendously rewarding experience thus far and looks forward to a long career and enduring relationships with his patients.

Dr. Polena’s patients will quickly recognize the quality and the personal dental care he delivers. Through effective treatment plan presentation and patient communication, he has been able to consistently exceed patient expectations.

Dr. Polena excels in dental implants, extractions, dentures/partials, crowns and bridges, laser dentistry, Invisalign, and more.

Kostika Polena, DDS

“I believe everyone deserves the benefit of a happy and healthy smile. As your dental provider, I am committed to helping you overcome any barriers preventing you from receiving the best oral health care possible.”

Early on Dr. Polena discovered a love and talent for art and later for science, graduating from UNLV with a degree in Biochemistry. Dentistry has turned out to be an ideal blend of his two passions. For Dr. Polena, dentistry has been a tremendously rewarding experience thus far and looks forward to a long career and enduring relationships with his patients.

Dr. Polena’s patients will quickly recognize the quality and the personal dental care he delivers. Through effective treatment plan presentation and patient communication, he has been able to consistently exceed patient expectations.

Dr. Polena excels in dental implants, extractions, dentures/partials, crowns and bridges, laser dentistry, Invisalign, and more.

Tira Emadi, DDS, MS

Dr. Emadi is a specialized implant-prosthodontic surgeon practicing in Long Beach, Ca. He received his D.D.S. (Doctor of Dental Surgery) degree in 2009 from Tehran Azad University of Dentistry, Tehran, IRAN. Dr. Emadi practiced general dentistry for several years. He was a prosthodontics preceptor at the University of California, San Francisco before he entered Nova Southeastern University College of Dental Medicine in Ft Lauderdale, FL where he received his specialty certificate in Prosthodontics as well as Master of Science in Dentistry. Dr. Emadi was serving as a Chief Resident during his residency. He was honored with the dental implant surgery award at the end of his residency. Dr. Emadi completed the Maxicourse dental implant education in the American Academy of Implant Dentistry. He also excels in digital dentistry.

Dr. Emadi is very passionate in practicing and teaching on full mouth dental implant rehabilitation as well as doing research. He had more than twenty-five presentations in different dental meetings and he published several papers in peer-reviewed dental journals. His presentation in 70th AAID annual conference received first-place award. He also received a second-place award in 29th Academy of Osseointegration Annual Meeting.

Dr. Emadi is an active member of American Dental Association (ADA), American Academy of Implant Dentistry (AAID), Academy of Osseointegration (AO) and he is a member of Young Clinician Committee in AO.