Realistic high-resolution lateral cephalometric radiography generated by progressive growing generative adversarial network and quality evaluations.

Realistic image generation is valuable in dental medicine, but still challenging for generative adversarial networks (GANs), which require large amounts of data to overcome the training instability. Thus, we generated lateral cephalogram X-ray images using a deep-learning-based progressive growing GAN (PGGAN). The quality of generated images was evaluated by three methods.

Comparing intra-observer variation and external variations of a fully automated cephalometric analysis with a cascade convolutional neural net.

The quality of cephalometric analysis depends on the accuracy of the delineating landmarks in orthodontic and maxillofacial surgery. Due to the extensive number of landmarks, each analysis costs orthodontists considerable time per patient, leading to fatigue and inter- and intra-observer variabilities. Therefore, we proposed a fully automated cephalometry analysis with a cascade convolutional neural net (CNN).

Fully automated estimation of arch forms in cone-beam CT with cubic B-spline approximation: Evaluation of digital dental models with missing teeth.

Background And Objective: To evaluate the automatic determination method for the arch form in cone-beam computed tomography (CBCT) images with cubic B-spline approximation on digital dental models using various types of missing teeth.

Methods: The maxilla and mandible from eight dental CBCT images with Class I occlusion and no missing teeth were used in this study. The dental arch determination algorithm using cubic B-spline approximation was modified by applying a smoothing function for reliable curve fitting to the digital dental models with various types of missing teeth.

Accuracy of a simplified 3D-printed implant surgical guide.

Statement Of Problem: The accuracy of 3D printing technology is essential for clinical applications. However, depending on the 3D printing method, machine, and environment, the accuracy varies even if the same computer-aided design (CAD) model is printed.

Purpose: The purpose of this in vitro study was to evaluate the differences between the CAD model and the printed parts with a simplified guide designed based on the implant guide and to compare the accuracy among 3 types of 3D printers.

Semi-automatic and robust determination of dental arch form in dental cone-beam CT with B-spline approximation.

Background And Objective: The dental arch form is generally used as a base for planning orthodontic treatments. It is, therefore, vital to determine the proper individual dental arch form for more accurate orthodontic treatment. We aimed to develop and validate a robust algorithm for semi-automatic determination of the dental arch form in dental cone-beam CT (CBCT) images with the cubic B-spline approximation.

Surgery-first approach in class III open-bite.

Recently, surgical-orthodontic treatment without preoperative orthodontic treatment (known as the surgery-first approach or SFA) has been proposed to improve facial aesthetics from the beginning of treatment, to shorten the entire treatment period, and to take advantage of the regional accelerated phenomenon for orthodontic tooth movement. The SFA concept involves the prediction and simulation of dental alignment, incisor decompensation, and arch coordination using manual setup models. Based on this, decisions regarding the surgical movement of the maxilla and mandible can be made to correct skeletal discrepancies through manual model surgery (MMS).

Volumetric, planar, and linear analyses of pharyngeal airway change on computed tomography and cephalometry after mandibular setback surgery.

Introduction: The purpose of this study was to use lateral cephalometry and computed tomography (CT) to examine the volumetric, planar, and linear changes in the pharyngeal airway after mandibular setback surgery.

Methods: The pharyngeal airways of 12 subjects who underwent mandibular setback surgery at Seoul National University Dental Hospital were assessed linearly and volumetrically on lateral cephalometric radiographs and CT before surgery and 6 months after surgery. The pharynx, nasopharynx, and oropharynx were evaluated by volumetric analysis.