Virtual Surgical Planning for Successful Second-Stage Mandibular Defect Reconstruction Using Vascularized Iliac Crest Bone Flap: A Valid and Reliable Method.

PURPOSE: Second-stage reconstruction of mandibular defects faces problems of anatomic disorder and bone displacement due to tumor resection. As a newer technique, virtual surgical planning (VSP) may help to increase the accuracy and efficiency of the complicated reconstruction. This study aims to evaluate the application of VSP and splint-guided surgery in second-stage mandibular reconstruction using vascularized iliac crest bone flap. METHODS: Between October 2016 and February 2018, 5 patients (3 men and 2 women) with mandibular defects of duration between 8 months and 8 years underwent VSP-aided secondary reconstruction in the School and Hospital of Stomatology of Wuhan University (Wuhan, China). Virtual surgical planning was performed and serial guiding splints were printed to replicate the design into the actual operation. The linear and 3-dimensional deviations after surgery were analyzed. Patient complications and feedback were recorded during follow up. RESULTS: All 5 patients underwent successful reconstruction using vascularized iliac crest bone flap. No serious donor sites or recipient site complications were observed after 10- to 28-month follow-up. In comparison with the presurgery designs, the linear deviations in coronal plane were 2.7 ± 0.4 mm (range, -2.2 to 3.9 mm) in measurements from the condylar head to the condylar head and 0.70 ± 0.6 mm (range, -0.1 to 1.7 mm) from the gonial angle to the gonial angle, and that in sagittal plane was 2.4 ± 0.88 mm (range, -3 to 4.4 mm) from the anterior inferior mandibular border to the center point on the condylar head to the condylar head line. The whole 3-dimensional deviation was 1.2 ± 1.7 mm in all patients. CONCLUSION: Well-designed splints can assist in precise mandibular reconstruction with high efficiency and accuracy, and thus are a reliable method for complicated second-stage mandibular reconstruction. However, to achieve a better outcome, a satisfactory design is required to adapt the complicated and varied defect.

Investigation on characterization of novel anti-bacterial chitosan/gelatin composite membranes loaded with quercetin via electrophoretic deposition.

Peri-implantitis is characterized by inflammation resulting from bacterial infections in peri-implant connective tissue. The purpose of this study was to prepare and characterize chitosan/gelatin (CSG)-based membranes with antibacterial agents to functionalize the surface of titanium (Ti) implants. CSG membranes were prepared on Ti substrates via electrophoretic deposition (EPD). Quercetin, an active flavonoid responsible for fulfilling various plant functions, was introduced as an antibacterial agent to be loaded into the membrane during preparation. The fabrication of quercetin-loaded CSG membranes via EPD was also investigated. Fluorescent microscope, Attenuated Total Reflection Fourier transform infrared spectroscopy, and X-ray diffraction results verified the entrapment of quercetin. The membranes swelled by 150% of mass after rehydration. The antibacterial effects of quercetin on Gram-positive bacteria, such as Staphylococcus aureus and methicillin-resistant Staphylococcus aureus, were verified by spread-plate, scanning electron microscopy, and live/dead staining. Cytological experiments showed that the biocompatibility of rat bone marrow mesenchymal stromal cells was promoted by quercetin-loaded membranes, exclusively in the group with the highest content of quercetin. The quercetin-loaded groups also enhanced the antineoplastic activity of MG-63 cells. These results suggested that quercetin-loaded CSG membranes were successfully fabricated via EPD. Thus, biocompatible and antibacterial membranes could be a potential strategy to functionalize Ti implants.