The accuracy comparison of 3D-printed post and core using castable resin and castable wax resin.

PURPOSE: The purpose of this research was to compare the accuracy of three-dimensionally (3D) printed post and core fabricated with two different materials: reinforced wax and castable resin. MATERIALS AND METHODS: Fifteen extracted single root central incisors were selected. Root canal treatment and tooth preparation for crown were performed on all teeth. Eleven millimeters post space was created with standardized prefabricated fiber post drill. Polyvinylsiloxane impression material was used for root canal impressions. Each impression was then 3D scanned using an extraoral scanner and cast posts and cores were designed using 3Shape software. The digitally designed post and cores were 3D printed with two different materials: castable wax resin and castable resin. The castable resin patterns were scanned before and after complete polymerization. The wax patterns were also scanned. Digital volumetric measurement using Geomagic® Control X™ software was performed to determine accuracy. RESULTS: The printed post and core had reduced volume (16.09 ± 3.839 mm3 ) compared to the digital design (17.828 ± 3.904, p < 0.05). Before complete polymerization, the accuracy of 3D printed resin pattern (16.464 ± 3.017) was found to be superior to post and core printed with wax (16.193 ± 3.018, p < 0.05). However, no volume difference was found between completely polymerized resin (16.09 ± 3.839) and wax (16.044 ± 3.834, p = 1). CONCLUSION: 3D printed post and core showed significant volume shrinkage from the digital files used to create them. However, different materials had no effect on the accuracy of 3D printed post and core.

The Use of 3D Printed Tooth Preparation to Assist in Teaching and Learning in Preclinical Fixed Prosthodontics Courses.

Tooth preparation for fixed dental prostheses is not an easy procedure to understand spatially, especially for first-year dental students. This technical report describes an innovative technique for assisting learning in preclinical fixed prosthodontics courses. Ideal full-contour tooth preparations are digitally scanned and 3D printed to the exact specifications of the ideal preparation. Students and faculty use these printed tooth preparations as teaching and learning tools to facilitate in 3D visualization for fixed prosthodontics courses.

Prosthodontic Considerations in Post-cancer Reconstructions.

The restoration of function after oncologic surgery of the oral cavity constitutes one of the major challenges facing head and neck oncology. Within the general objective of securing esthetic as well as functional reconstructions, dental rehabilitation is crucial for achieving a good outcome. Adequate dental rehabilitation allows the patient to chew food and considerably improves speech and swallowing. These reconstructions will be driven biologically or prosthetically following surgical design and outcome.