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Within the limitations of this study, we conclude that the retentive force decreases with an increase in implant inclination, whereas the lateral force increases, except for in magnetic attachments.

Background In some cases, a dentist cannot solve the difficulties a patient has with an implant because the implant system is unknown. Therefore, there is a need for a system for identifying the implant system of a patient from limited data that does not depend on the dentist’s knowledge and experience. The purpose of this study was to identify dental implant systems using a deep learning method. Methods A dataset of 1282 panoramic radiograph images with implants were used for deep learning. An object detection algorithm (Yolov3) was used to identify the six implant systems by three manufactures. To implement the algorithm, TensorFlow and Keras deep-learning libraries were used. After training was complete, the true positive (TP) ratio and average precision (AP) of each implant system as well as the mean AP (mAP), and mean intersection over union (mIoU) were calculated to evaluate the performance of the model. Results The number of each implant system varied from 240 to 1919. The TP ratio and AP of each implant system varied from 0.50 to 0.82 and from 0.51 to 0.85, respectively. The mAP and mIoU of this model were 0.71 and 0.72, respectively. Conclusions The results of this study suggest that implants can be identified from panoramic radiographic images using deep learning-based object detection. This identification system could help dentists as well as patients suffering from implant problems. However, more images of other implant systems will be necessary to increase the learning performance to apply this system in clinical practice.

Because the abutment becomes the fulcrum, and the denture base over the coping is usually thin, the overdenture is susceptible to fracture. We hypothesized that rational reinforcement can reduce strain and prevent deformation and fracture of the overdenture. We investigated the effect of reinforcement on overdenture strain around the copings and at a midline. A mandibular edentulous model with a 2-mm-thick artificial mucosa and abutment teeth installed bilaterally in the canine position was produced. The coping had a dome-shaped upper surface with a height of 6 mm. On the lingual polished surface, strain gauges were attached at the canine position and at the midline. A vertical load of 49 N was applied on the occlusal surface. Among several kinds of reinforcements, the cast metal reinforcement that covers both the midline and the coping top significantly reduced the strain on the overdenture. It is suggested that this simple reinforcement is effective in preventing deformation and fracture of the overdenture.

There appears to be much confusion or misinformation worldwide regarding mouthguards and their use in sports. In an effort to clarify where the international dental community stands on mouthguards and mouthguard research, the workshop looked at some important questions. The goal was to one day formulate consensus statements related to these questions, which will be based on current scientific evidence-based research, to motivate the international community of the importance of dentally fitted laminated mouthguards and the wearing of them by athletes of all sports. There are only five sports in the United States that require the use of mouthguards. If, through workshops such as this, the importance of wearing dentally fitted laminated mouthguards can be demonstrated, then more sports may require their athletes to wear them. K E Y W O R D Sconcussion prevention, mouthguards, performance enhancement, sports dentistry, sportsguards