A deep learning approach to automatic teeth detection and numbering based on object detection in dental periapical films.

Journal: Scientific reports
PMID:

Abstract

We propose using faster regions with convolutional neural network features (faster R-CNN) in the TensorFlow tool package to detect and number teeth in dental periapical films. To improve detection precisions, we propose three post-processing techniques to supplement the baseline faster R-CNN according to certain prior domain knowledge. First, a filtering algorithm is constructed to delete overlapping boxes detected by faster R-CNN associated with the same tooth. Next, a neural network model is implemented to detect missing teeth. Finally, a rule-base module based on a teeth numbering system is proposed to match labels of detected teeth boxes to modify detected results that violate certain intuitive rules. The intersection-over-union (IOU) value between detected and ground truth boxes are calculated to obtain precisions and recalls on a test dataset. Results demonstrate that both precisions and recalls exceed 90% and the mean value of the IOU between detected boxes and ground truths also reaches 91%. Moreover, three dentists are also invited to manually annotate the test dataset (independently), which are then compared to labels obtained by our proposed algorithms. The results indicate that machines already perform close to the level of a junior dentist.

Authors

  • Hu Chen
  • Kailai Zhang
    Department of Electronic Engineering, Tsinghua University, Beijing, China. Electronic address: zhangkl17@mails.tsinghua.edu.cn.
  • Peijun Lyu
    Center of Digital Dentistry, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081, PR China.
  • Hong Li
    Department of Public Health Sciences, Medical College of South Carolina, Charleston, SC.
  • Ludan Zhang
    Center of Digital Dentistry, Peking University School and Hospital of Stomatology & National Engineering Laboratory for Digital and Material Technology of Stomatology & Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health & Beijing Key Laboratory of Digital Stomatology, Beijing, China.
  • Ji Wu
    Department of Urology, Nanchong Central Hospital, Nanchong, Sichuan, China.
  • Chin-Hui Lee
    School of Electrical and Computer Engineering, Georgia Institute of Technology, Georgia, USA.