Meet Our Team

Our Dentists

Dr. Tim Sellner

Dr. Tim Sellner, B.Sc, DDS


Dr. Sellner obtained his Bachelor of Science and Doctor of Dental Surgery degrees from University of Western Ontario, and has been with TechTown Dentistry since opening in 2007.


Dr. Sellner enjoys meeting new people and providing superior dental care in a technologically advanced office setting.  He also enjoys continuing education and lifelong learning to offer his patient's the most up-to-date knowledge and treatment options.  Dr. Sellner is a member of the Canadian Dental Association, Ontario Dental Association and has recently been elected President of the Waterloo Wellington Dental Society.


Dr. Sellner was born and raised in Waterloo, Ontario and still resides in Waterloo with his wife, Hayley and daughters, Brooklyn and Olivia.  In Dr. Sellner's spare time, he enjoys sailing, downhill skiing and golfing.

Dr. Tim Sellner

Dr. Marcia Domingos, B.Sc, M.Sc., BDS


Dr. Marcia Domingos obtained her Bachelor of Science and Master of Science degrees from the University of Waterloo. She then graduated with honours with a Bachelor of Dental Surgery degree from the University College Cork, in Ireland.


Dr. Domingos is passionate about building trusted relationships with her patients. She strives to help her patients feel comfortable, relaxed, and cared for within the dental setting. 


Dr. Domingos is also committed to giving back to the community. During her time as a student in Waterloo, she volunteered with Hardy Hearts and UW-Well Fit. As a dental student she devoted much of her spare time to mental health awareness and research.


In her personal life, Dr. Domingos loves to spend time with her husband and daughter, Gioia. She loves to run, bake, and is an advocate for living a balanced healthy lifestyle.

Our Dental Hygienists

Dr. Tim Sellner

Hayley, RDH, RHN, Hygiene Coordinator


Hayley obtained her Dental Hygiene diploma in 2007. Prior to her Dental Hygiene degree she completed her level II Dental Assisting certificate. Hayley is a member of the College of Dental Hygientists of Ontario & the Ontario Dental Hygiene Association. Beyond her dental credentials Hayley is also a Registered Nutritionist.


Hayley is dedicated in providing optimal oral health and overall health through education and preventive treatment.  She keeps her knowledge current by being part of a dental hygiene study group where their main focus is Periodontal knowledge.


Hayley was born and raised in Peterborough and currently resides in Kitchener with husband Tim, daughters Brooklyn and Olivia, and their dog, Charlie. When not in the office, Hayley loves to run, ski, play tennis and enjoys a good glass of wine. 

Dr. Tim Sellner

Alana, RDH


Alana has worked with TechTown Dentistry since we first opened in 2007.  She obtained her certification in Level II Dental Assisting from Fanshawe College in 2004 prior to receiving her Dental Hygiene diploma in 2006 from Georgian College.  Alana is an active member at the College of Dental Hygienists of Ontario and Canadian Dental Hygienists Assocation.


Alana loves to meet new people every day and feels she can make a difference in helping our community improve their oral health and their overall health.  She finds her job rewarding as she applies her knowledge gained from many continuing education courses and feels continued learning is curcial in her ability to advise her patients regarding their oral heath condition and needs.


Alana is originally from Kincardine, Ontario where she spends a lot of her spare time with family and friends.  Alana also enjoys horse back riding and volleyball.

Dr. Tim Sellner

Nikki, RDH


Nikki obtained her dental hygiene advanced diploma in 2014 from Canadore College. She also completed her Dental Assisting levels I  &  II from Canadore College in 2011. Nikki is currently licensed with CDHO, and has been licensed in Alberta and British Columbia before returning back to Ontario. 


Nikki has a passion for educating her clients and making them feel comfortable during their visit. 


Nikki was born and raised in Peterborough, Ontario. She currently resides in Cambridge with her husband Matthew and their son, Wayne, a dog named Earl, and cat named Neville.  Nikki enjoys baking, reading, knitting and yoga.

Dr. Tim Sellner

Krista, RDH


Krista graduated with an advanced diploma from Algonquin College in 2017. She is a current member of the College of Dental Hygienists of Ontario and of the Ontario Dental Hygiene Association.


Krista likes to bond with her patients, and get to know their oral health goals. This allows her to help her patients in maintaining and improving their dental health. Krista believes that everyone should have a smile that they can be proud of.


After growing up in Cambridge, ON, Krista lived in different cities, including Victoria, B.C., Lake Louise, AB., and Ottawa, ON., before returning to live in Waterloo. In her free time, she enjoys hot yoga, playing volleyball, reading, and baking.

Dr. Tim Sellner

Ashley, RDH


Ashley obtained her Dental Hygiene diploma in 2010 from the Canadian Institute of Dental Hygiene in Hamilton. Prior to completing her Dental Hygiene diploma, she completed an undergraduate degree in Environmental Studies from the University of Waterloo.  Ashley is an active member of the College of Dental Hygienists of Ontario and the Ontario Dental Hygiene Association.


Ashley is dedicated to helping achieve optimal oral health while creating lasting connections with all her patients.


Ashley was born and raised in Waterloo where she still resides with her husband Peter, her son, Colton and daughter, Brinley.  In her spare time Ashley enjoys travelling and being active with her family. 

Dr. Tim Sellner

Melissa, RDH


Melissa graduated with her Dental Hygiene Diploma (Honours) from Algonquin College in 2001. Prior to dental hygiene, she attended OBC for Dental Assisting in 1998 and Niagara College for Registered Practical Nursing.


She maintains registration with the College of Dental Hygienists of Ontario, the Ontario Dental Hygienists Association and the Canadian Dental Hygienists Association. She uses her years of experience to assist people in obtaining their oral health goals and enjoys meeting new people and learning new things.


Melissa and her husband both attended high school in Fergus, Ontario, where they enjoy life with their rescue dog, Tank. In their spare time they enjoy camping, biking and spending time with their family.

Dr. Tim Sellner

Jordan, RDH


Jordan has been working as a Dental Hygienist since she obtained her Advanced Dental Hygiene Diploma in 2017. She is a member of the ODHA and continues to stay up to date and educated so that she can provide excellent patient care. 


Jordan is very passionate about oral health and educating her patients. Her contagious smile and positive attitude makes her patients feel comfortable and at ease during their visit. 


Jordan currently resides in Palmerston, ON and in her free time enjoys playing broomball, baseball and spending time with friends and family. 

Our Dental Assistants

Dr. Tim Sellner

Shakilah, CDAII 


Shakilah graduated from CDA II from Everest College in 2008.  She has been working in Waterloo ever since.  Shakilah is passionate about educating clients about good oral hygiene and providing them with the best possible dental experience. 


Shakilah enjoys living an active and healthy life style, she currently resides in Waterloo with her husband and 2 daughters Neveah and Jazmine.


Dr. Tim Sellner

Kellie, CDAII


Kellie obtained her Certified Dental Assistant Level II diploma with honours in 1997.  Kellie enjoys working in healthcare.  Seeing patients happy with the treatment they receive and the end results are very rewarding for her. 


During her spare time, Kellie enjoys gardening, walking, and loves a great action movie.  Kellie was born in Gander, NL and now resides in Kitchener with her daughters.

Dr. Tim Sellner

Rashmeet, CDAII


Rashmeet has been working as a Certified Level II Dental Assistant since graduating from Medix College in Kitchener in 2013. 


Throughout her years of experience assisting, Rashmeet enjoys meeting new people and learning new procedures in Dentistry.  Seeing patients happy with the care we provide is very fulfilling for her.


Rashmeet and her family live in Waterloo with their dog, Max. She enjoys spending time with family and occasionally enjoys a good murder mystery show.

Our Office Administrators

Dr. Tim Sellner

Katherine, CDA, Dental Administrator


Katherine received her diploma in Dental Assisting in 1990 from Durham College.  She worked as an assistant for 10 years before taking a few years off to raise her 2 sons.  Katherine re-entered the work force as a Dental Receptionist for 12 years before joining TechTown Dentistry.


Shes love working in the dental field! The bond and trust that is created with patients is such a wonderful experience. 


Katherine was born and raised in Niagara Falls and currently resides in Waterloo with her husband Chris and two sons, Cody and Kyle.

Dr. Tim Sellner

Leslie, CDAII, CDR, Treatment Coordinator


Leslie graduated from Fanshawe College's Pre-Health Sciences program in 1991. She then went onto Algonquin College in 1992 to complete her CDA diploma and finished at Holland College in P.E.I in 1992 with a Certification CDAII.  Leslie also completed the Certified Dental Reception credential in 2003. 


Leslie was invited to be on the ODAA committee to create what is now the CDTC course (Certified Dental Treatment Coordinator) in 2002.   She is an active member of the ODAA.  Leslie values the opportunity to spend time educating patients on their dental journey, has a thrist for knowledge and keeps up with continuing education. 


Leslie was raised in Elmira where she resides with her husband Steve and their children, Tanis and Joshua.  Away from the office she cheers on her kids at the hockey arena, coaches baseball and enjoys hiking, fishing, golfing, and swimming.

Dr. Tim Sellner

Lesley, CDAII, Office Manager


Lesley graduated as a Certified Level II Dental Assistant in 1996 from Niagara College.  She has spent many years experiencing the different roles of dentistry from Dental Assistant, Dental Claims Assessor, Dental Software Designer for a major insurance company, Dental Administrator, Treatment Coordinator and Office Manager. Her passion has always been providing excellent customer service and outstanding dental care to all patients.


Lesley was raised in the KW Region where she currently resides with her husband, Dennis and their children, Matthew, Megan and Charlotte.  Outside of the office, she enjoys watching their kids sporting events and after-school programs.  She loves gardening, home decorating, reading and walking the family dog, Georgia.