She graduated from the University of Sydney and undertook postgraduate training in Periodontics at the University of London, followed by a lectureship in Periodontology at the Eastman Dental Hospital, University of London. She spent many years in specialist practice in Brisbane and as a Senior Research Fellow at The University of Queensland.　She has been active in clinical and basic research, has published widely in the international literature and is on the editorial board of several international journals. As director of the Clinical Research Group of the Sir John Walsh Research Institute Mary established the dental practice based research network (PBRN) at the University of Otago and built collaborations with PBRNs internationally.