Three-dimensional printing in integrated multi-modality imaging approach for management of prosthetic valves infective endocarditis.

After heart failure, infectious endocarditis is the second leading cause of death in patients with prosthetic valves. Aortic pseudoaneurysms are a serious complication of infective endocarditis in mechanical or bioprosthetic aortic prostheses. Diagnostic and management challenges are posed by aortic pseudoaneurysms. In these cases, a multi-modality imaging approach with a heart team is recommended. We described two cases of aortic pseudoaneurysms that developed as a result of infective endocarditis. The first case involved a TAVI patient who developed infective endocarditis as a result of diabetic foot complications. Because traditional echocardiography and computed tomography failed to show the anatomy of the lesion, we used 3D printing to show the anatomy, extension of the pseudoaneurysm, and proximity to the right coronary artery. The second case involved a patient who underwent Bentall's surgery with an aortic root and mechanical aortic valve and later developed infective endocarditis complicated by pseudoaneurysms. In this case, 3D printing was used for preoperative surgical planning.

Fracture resistance and failure location of zirconium and metallic implant abutments.

AIM: The purpose of this study was to evaluate the fracture resistance and failure location of single-tooth, implant-supported, all-ceramic restorations on different implant abutments subjected to a maximum load. METHODS AND MATERIALS: Forty Certain 3i implants and 20 ITI Straumann implants were used in this study in combination with 20 UCLA abutments, 20 ZiReal abutments, and 20 synOcta Ceramic Blanks to form three groups according to abutment type. All 60 abutments were prepared with standard measurements: a 1.0 mm deep chamfer, 2.0 mm of incisal reduction, and a total height of 7 mm. Sixty IPS Empress 2 full ceramic crowns were fabricated and cemented on each abutment with a resin cement. Static loading was simulated under maximum loading and fracture locations were noted. RESULTS: The mean load to failure data and standard deviations for the three groups were as follows: Group 1 (792.7 N +/- 122.5) and Group 3 (793.6 +/- 162.3) showed no significant difference in fracture resistance while the values for specimens in Group 2 (604 N +/- 191.1) had the lowest mean value and were significantly lower. In Group 1, 16 crowns and four abutment fractures were reported, while in Group 3, 17 crowns and three abutments fractured. Group 2 actually showed three types of fractures. Two specimen fractures were located at the implant level, six with fractures occuring within the Empress 2 all-ceramic crown, and the remaining 12 failures were located at the abutment level. CONCLUSION: Within the limitations of this laboratory study, the following conclusions were drawn: The mean load-to-failure values for all three groups were well above the reported normal maximal incisal load range. The load to failure for both the zirconium oxide (ZrO2) abutments (ZiReal on 3i Certain implants and synOcta Ceramic Blanks on SLA ITI Straumann implants) had mean fracture loads of 792.7 N (+122.6) and 604.2 N (+191.2), respectively. The zirconium oxide (ZrO2) ZiReal and titanium (UCLA) abutments on the 3i Certain implants had statistically significantly higher fracture loads (792.7 N and 703.7 N, respectively) than those recorded for the 3i Ceramic Blank abutments on the SLA ITI Straumann implant (604.2 N). The ITI Straumann Ceramic Blank abutments showed uniform fracture behavior. Fracture mainly emanated from the cervical buccal aspect of the abutment. CLINICAL SIGNIFICANCE: The three abutments tested showed they can withstand clinical loads above the normal range of mastication.