Dr McKenzie graduated from the University of London in 1993 with a bachelor's degree in dental surgery. She was awarded the Prize in Biochemistry, Physiology, Anatomy and Special anatomy.
Her next four years was spent working as general dentist in a variety of posts acquiring valuable skills in dealing with children and patients with special needs.
In 2001 she graduated from the University of Sydney with a Masters Degree in Orthodontics and spent the next five years gaining extensive experience in private practice working in one of the leading orthodontic practices in Sydney's North Shore.
Dr McKenzie founded the Smiles Orthodontic Practice in 2006 to cater for her patients living in the Inner West of Sydney.