The use of autologous cartilage and bone grafts remains the gold standard in augmentation rhinoplasty performed to reconstruct of the nasal dorsum. Meanwhile, limited number of available sources, donor site morbidity, and unpredictable graft resorption represent significant disadvantages of autografting. The aim of this study is to test combination of autologous stromal vascular fraction (SVF) and commercially available bone substitutes (BSs) as new tissue-engineered grafting material (GM) for rhinoplasty. A series of consecutive cases includes four adult patients who underwent rhinoplasty to correct saddle nose deformity (SND) using the new graft technique. SVF was isolated from liposuction aspirate using standard methodology of enzymatic digestion. Two types of BSs were combined with SVF: Bio-Oss granules to create a moldable graft (M-graft), and block-shaped BoneMedik-S to create rigid grafts (R-grafts). The moderate SND was treated using an M-graft. In case of major or complex SND, the nasal dorsum was reconstructed with dorso-columellar L-shaped framework made of R-grafts. The results were evaluated over a period of 6 months to 3 years postoperatively using photogrammetry and FACE-Q appearance appraisal scales. Computerised tomography (CT) scanning of the reconstructed nose and histological analysis of grafted material were also carried out. No complications were observed. The photograms show the restoration of the correct contour of the nose. FACE-Q appraisal scale scores increased significantly, including satisfaction with nose appearance, psychological well-being, and social function. In CT evaluation, there was no substantial resorption or warping of the grafts. Histological findings show osteogenic remodeling of the grafted material. Thus, combining autologous SVF with BSs is a promising strategy for developing rhinoplasty GM.
Aim: In this study, the finite elements analysis (FEA) was performed on an intramedullary (IM) pin to be used in the canine femur. The 03 different biomaterials [17-4-precipitated hardened (PH)-stainless steel (SS), nickel alloys (Ni)-625, titanium alloys (Ti)-6Al-4V] were selected for comparative FEA. In-vitro analysis was also performed in simulated body fluid (SBF) on selected biomaterials for possible application in the canine femur. Methods: FEA was performed on 03 different biomaterials (17-4-PH-SS, Ni-625, and Ti-6Al-4V) based on Von-Mises criteria (at an applied load of 1,500 N, cell type: tetrahedron, grit size: 0.15 mm, number of nodes: 213,989 and elements: 145,012). The distal end of the IM pin was fixed, and the load was applied to the proximal end. In-vitro analysis was performed (on a potentiostat setup) to establish the corrosion rate of various biomaterials (17-4-PH-SS, Ni-625, and Ti-6Al-4V). Results: The results of FEA show Ni-625 absorbed the maximum Von-Mises stress in the case of tensile and compression loading (104.12 MPa). In the case of torsion loading, the maximum Von-Mises stress was absorbed by 17-4-PH-SS (63.331 MPa). The maximum Von-Mises elastic strain (0.00093473) was observed for Ti-6Al-4V while tensile and compression and minimum deformation (0.013869 mm) in tensile loading. Conclusions: Based on this study, the maximum safety factor against failure (N) [ratio of 0.2% of yield strength (σy) to the Von-Mises stress (σv)] was observed as 10.75, 11.38, and 15.89, respectively, for tensile, compression, and torsional loading in the case of Ti-6Al-4V. Also, the better biocompatible material for the orthopaedic implant application based on the corrosion result is Ti-6Al-4V due to a lower corrosion rate (2.63211 × 10–10 mm/year) in comparison to 17-4-PH-SS and Ni-625. Overall, the Ti-6Al-4V is a better material than 17-4-PH-SS and Ni-625 for the intended application.