Deep learning and clustering approaches for dental implant size classification based of periapical radiographs

Abstract

This study investigated two artificial intelligence methods for automatically classifying dental implant size based on periapical radiographs. The first method, deep learning (DL), involved utilizing the pretrained VGG16 model and adjusting the fine-tuning degree to analyze image data obtained from periapical radiographs. The second method, cluster analysis, was accomplished by analyzing the implant-specific feature vector derived from three key-point coordinates of the dental implant using the k-means + + algorithm and adjusting the weight of the feature vector. DL and clustering model classified dental implant size into nine groups. The performance metrics of AI models were accuracy, sensitivity, specificity, F1-score, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUC). The final DL model yielded performances above 0.994, 0.950, 0.994, 0.974, 0.952, 0.994, and 0.975, respectively, and the final clustering model yielded performances above 0.983, 0.900, 0.988, 0.923, 0.909, 0.988, and 0.947, respectively. When comparing the AI model before tuning and the final AI model, statistically significant performance improvements were observed in six out of nine groups for DL models and four out of nine groups for clustering models based on AUC. For clinical applications, AI models require validation on various multicenter data.