Meet The Team

Our Offices

You work hard every day to keep your family smiling and we want to be a part of that mission! As your local Philadelphia, PA orthodontists, our team is proud to offer comprehensive orthodontic services that are convenient, comfortable and cost-effective. Our goal is to help you and your family maintain a happy, healthy smile for years to come.

Hanel Choi, DDS

Dr. Hanel Choi, a Virginia native, received her Bachelor's Degree in Chemistry at the University of Virginia. She later went on to receive her Doctorate in Dental Surgery from Virginia Commonwealth University School of Dentistry. Realizing she had profound a love for orthodontics and braces, Dr. Choi pursued her Certificate in Orthodontics from the Tufts University School of Dental Medicine. Dr. Choi is excited to be working in her dream profession in the Greater Philadelphia area a place she loves for its food, culture, and diversity. As an orthodontist, Dr. Choi finds it especially worthwhile to individualize the care she provides to her patients in order to create wonderful smiles. She has a passion for working with adolescents and teenagers and finds great joy in seeing them come out of their shell with the help of orthodontic treatment. You can frequently find Dr. Choi engaging with adult patients one-on-one to discuss their treatment and further their education on good oral hygiene. In her free time, Dr. Choi loves spending time baking cookies for her friends and family and trying out new recipes. She is also an avid yoga student and is currently trying to master the handstand and the crow pose!

Evan Tran, DDS

Trapped in a young man’s body with a wise man’s brain, Dr. Evan Tran considers himself to be a great listener. To this end, Dr. Tran strives to understand his patients’ treatment goals and works with them to thoroughly explore how to achieve them. As a native Florida Gator, he chomped his way through The Big Apple for dental training at Columbia University. Not long after, he completed his orthodontic training at Seton Hill University in the small town of Greensburg, Pennsylvania. It was here, that he added the hobby of blacksmithing to his repertoire which also includes skiing, water sports, and computing. In 2016, Dr. Tran moved to Philadelphia to join Rich Orthodontics. He looks forward to meeting you and wants you to know that he will do his best to give you the smile you deserve!

Hamid Hashemi, DMD

Inspired by his love for art and science, Dr. Hamid Hashemi pursued a career in orthodontics. After graduating from Temple University Kornberg School of Dentistry, Dr. Hashemi attended Seton Hill University’s Orthodontic Residency Program. As an orthodontist, Dr. Hashemi is able to utilize his skills to not only restore the function and health of his patients’ teeth, but also to witness smile transformations, and a tangible boost in their confidence. Seeing the positive impact an attractive smile can make in a person’s life is extremely rewarding, he strongly believes in treating patients as he would his own family with care and compassion. In this vein, he strives to be more than a healthcare provider; he aims to serve as a sympathetic individual who can be a role model to others. In his free time, Dr. Hashemi enjoys camping, participating in recreational sports, writing poetry, and spending time with his family.

Silke Cummings, DMD, MSD

Born in Kingston, Jamaica, Dr. Silke Cummings always felt she would pursue something in medicine as her mother was a doctor. However, after coming to the US for high school, she always happened to find herself hanging around in the dental clinic after her orthodontic appointments. When she finally got to experience a week-long dental summer program at the University of Pennsylvania, her heart became set on dentistry.

Dr. Cummings decided to attend UPenn where she majored in Biology and then continued there to receive her Doctor of Medicine in Dentistry degree. Although she found dental school very demanding, she received the Dean’s Scholarship all 4 years and graduated cum laude. She then went on to complete her orthodontics residency at the University of the Pacific in San Francisco. She is a member of the AAO (American Association of Orthodontists) and is an ABO board certified orthodontist. She is passionate about volunteer work, and especially enjoys interacting with the visitors at her local soup kitchen. In her free time, she enjoys jigsaw puzzles and being outdoors.
Silke Cummings, DMD, MSD

Sarah Prehn, DDS

Dr. Sarah Prehn is originally from Kingston, NY. Her mother worked as a dental assistant, and after shadowing her in high school at the office, she knew she wanted to be a dentist. Dr. Prehn completed her undergraduate degree at the State University of New York at New Paltz. She then went on to graduate with a Doctorate of Dental Surgery from New York University as the top woman in her class, and obtained her Orthodontic Certificate from Saint Barnabas Hospital in Bronx, NY. After residency, Dr. Prehn became a Diplomate of the American Board of Orthodontics. To further her dental knowledge, Dr. Prehn attends conferences and courses throughout the year. Her most recent coursework includes completing an advanced fellowship in clear aligner treatment. Dr. Prehn is also a member of the American Association of Orthodontics, Omicron Kappa Upsilon Dental Honors Society, the American Dental Association and the Pennsylvania Dental Association.

When asked why she chose orthodontics as her profession, Dr. Prehn said: “Practicing orthodontics allows me to help people in many ways. Some people seeking treatment are unhappy with the position of their teeth and want to straighten them for aesthetic purposes. For these patients, giving them the smile of their dreams gives them self-confidence. Other people are looking to correct more serious problems that affect eating, speaking and tasks that help them function in life. Whether their problem is mild or severe, it is so rewarding to see patients walking out of the office feeling happy about their treatment.”

Dr. Prehn now lives in Wynnewood, PA with her husband, Joseph and her kitten, Maisie. When she isn’t working, you can usually find her outside running. Her other favorite pastimes include going to musical concerts, traveling, reading and spending time with friends and family. Dr. Prehn is a singer and plays the trombone and piano. In addition to her work in the office, Dr. Prehn volunteers her time at local health fairs, performing dental screenings and teaching people about keeping their teeth healthy. She is also an active member in her church, getting to know her neighbors and giving back to the community.
Dr. Sarah Prehn
Rich Orthodontics
Philadelphia, PA
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