Navigational exploration of bony defect mimicking a solid lesion of the mandible compared to conventional surgery by young professionals.

INTRODUCTION: The aim of the current study was to evaluate the accuracy of resection a solid lesion in an acrylic lower jaw by young professionals using a dynamic computer-assisted surgical system comparted to conventional surgery technique. MATERIAL AND METHODS: Twenty students performed the removal of the lesion conventionally and twenty students did the operation with a dynamic computer-assisted surgical system. Both groups were compared regarding the defect size, operation time, and surgical complications. RESULTS: The defect size in the jaw was significant smaller with the navigated surgery (p < 0.001). Operation time was shorter without navigation system, but no significance was found (p = 0.137). Without navigation system three young professionals perforated the lingual cortex. DISCUSSION: Navigated surgery can immediately be used by young professionals and support young surgeons in everyday clinical practice, especially in operations with difficult anatomic situations.

Pronounced mediastinal emphysema after restorative treatment of the lower left molar-a case report and a systematic review of the literature.

This case report presents an iatrogenic induced mediastinal emphysema after restorative treatment of the lower left second molar, aimed to highlight the potential life-threatening consequences, and providing diagnostics and treatment concepts of complicated dental induced emphysema based on literature review. A 74-year-old female patient was admitted to the emergency department due to a fall on her shoulder. Additional finding was a significant swelling of the face and neck. In the computer tomography of the head, neck, and thorax, a humerus fracture and pronounced soft tissue emphysema from the infraorbital region to the mediastinum was detected. The patient reported that she had been treated by her dentist 4 days earlier. The treatment had to be discontinued after beginning of a pronounced swelling. Other reasons for the emphysema could be excluded out on an interdisciplinary teamwork. The patient was monitored as an inpatient for 5 days and received intravenous antibiotic therapy. This case report shows the rare complication of pronounced mediastinal emphysema after root canal treatment. Emphysema should always be a differential diagnosis of soft tissue swelling and, in case of doubt, a general medical presentation should be made.

Learning Curve and Comparison of Dynamic Implant Placement Accuracy Using a Navigation System in Young Professionals.

The aim of the current study was to evaluate the learning curve and accuracy of implant placement by young professionals using a dynamic computer-assisted surgical system for dental implant placement. Ten students tried to place eight implants with a dynamic surgical system in predefined positions on two consecutive weekends, resulting in 160 implant placements in total. Postoperatively, the positions of the implants were scanned with an intraoral scanner and compared for deviations at the entry point, the apex, as well as angular deviations to the master model. The mean values of all measurements improved; statistical significance was found for the changes in the angle as well as for the position of the implants to the apex (p < 0.001). Furthermore, the young professionals indicated subjective improvement in handling the dynamic surgery system. Navigated surgical dental implant placement can be learned quickly and can support young professionals in everyday clinical practice, especially in difficult anatomic situations.

Assessment of marginal integrity of five different polymers in retrograde root-end filling following apicoectomy: An in-vitro analysis with scanning electron microscope and micro-radiography.

PURPOSE: The aim of the study was to evaluate marginal adaptation properties of five different sealers used as root filling material. MATERIALS: Apical resection was performed on 100 canals of 50 maxillary premolars in slaughtered pigs. The root end of 24 canals were retrogradely filled with Diaket™, 37 root canals with Super-EBA™ including 18 with Super-EBA™. Regular and 19 with Super-EBA™ fast, 20 canals with ProRoot® MTA and 19 canals with AH-Plus™. For quantitative examination, scanning electron microscope (SEM) analysis and for qualitative examination, microradiography was performed. RESULTS: Diaket™ achieved an overall average of 4.872 microns gap value as the best result. The mean values of marginal gap widths of AH-Plus™ and Super-EBA™ were almost with 8.044 microns and 9.951 microns in about the same magnitude, followed by Super-EBA™ Regular with 11,560 microns. Highest marginal gap value was found for ProRoot® MTA with 18.343 microns ( p < 0.001). CONCLUSIONS: Both in terms of its marginal integrity and material properties, Diaket™ is the most suitable material for retrograde obturation. A preliminary version of the current paper could be found at www.researchsquare.com/article/rs-6198/v1.