Greig graduated from University of Glasgow in 2012 with honours and completed a 2-years longitudinal dental foundation training programme, undertaking rotations in oral surgery, community dental services and general practice. He completed the Diploma of Membership of the Faculty of Dental Surgery through the Royal College of Surgeons of Glasgow (MFDS RCPS(Glasg)) in 2014. He completed further training in oral-maxillofacial surgery, orthodontics and paediatric dentistry in the West of Scotland.

He started his specialist training in Newcastle in 2016, and successfully passed both a master’s in clinical research (with distinction) and Membership in Paediatric Dentistry specialist exams in 2019. He then completed his PhD, funded by a prestigious personal NIHR Doctoral Research Fellowship, entitled the DECIDE study “Dental ExtraCtion versus filling In aDult teeth: an economic evaluation”, based at Newcastle University.

In 2023, Greig was appointed as a Clinical Lecturer in Paediatric Dentistry, whilst continuing to provide specialist care to paediatric patients at Newcastle Dental Hospital. Greig is actively involved in research, with several peer reviewed publications in the field of paediatric dentistry. He has published and presented nationally and internationally and was co-author on both the recently updated International ‘Best clinical practice guidelines for Molar-Incisor Hypomineralisation’ and the Royal College of Surgeons guideline for the Extraction of First Permanent Molars in Children.

Greig splits his time between working at Newcastle Advanced Dentistry and completing higher post-specialist consultant training in Paediatric Dentistry at Newcastle Dental Hospital.