Health and Technology

, Volume 9, Issue 5, pp 715–724 | Cite as

Identification and analysis of photometric points on 2D facial images: a machine learning approach in orthodontics

  • Gururajaprasad Kaggal Lakshmana RaoEmail author
  • Arvind Channarayapatna Srinivasa
  • Yulita Hanum P. Iskandar
  • Norehan Mokhtar
Original Paper


The lack of an effective and automated facial landmark identification tool has prompted us to design and develop a smart machine learning approach. The study aims to address two objectives. The primary objective is to assess the effectiveness and accuracy of algorithmic methodology in identifying and analysing facial landmarks on two dimensional (2D) facial images and the secondary objective is to understand the clinical application of automation in facial landmark identification. The study has utilised 418 facial landmark points and 220 landmark measures from 22 2D facial images of volunteers. The study has used a deep learning algorithm ‘You Only Look Once (YOLO)’ to determine the accuracy of the developed system and its clinical applications. The system identified 418 landmarks in total with facial recognition being 100%. Of the total 220 landmark measures, the system provided 48 (21.81%) measures in the error range of 0 to 1 mm, 75 (34.09%) measures in the error range of 2 to 3 mm, 92 (41.81%) measures in the error range of 4 to 5 mm followed by 5 (2.2%) measures in the range of 6 mm. The smart and innovative approach provides valuable training and a helpful tool for the students performing the clinical facial analysis. The automated system with its effective and efficient algorithm delivers fast and reliable landmark identification and analysis.


Orthodontic photometric points Orthodontic facial measures Frontal facial photography YOLO Machine learning algorithm Deep learning Orthodontics Smart learning 


Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

No ethical approval was required as the study only utilised images of volunteers faces. Suitable written consent was taken from each of the volunteers before the start of the study.

Informed consent

Informed written consent was obtained from all individual participants included in the study.


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Copyright information

© IUPESM and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Craniofacial and Biomaterial Science Cluster, Advanced Medical and Dental InstituteUniversiti Sains MalaysiaPenangMalaysia
  2. 2.Cognitive Computing and Data Science Research Lab, Global Technology OfficeCognizant Technology SolutionsBengaluruIndia
  3. 3.Graduate School of BusinessUniversiti Sains MalaysiaPenangMalaysia

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