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In engineering design, material alternatives evaluate according to different criteria depending on the objectives of the problem. Performance ratings for different criteria are measured by different units, but in the decision matrix in order to have a valid comparison all the elements must be dimensionless. However, a lot of normalization methods have been developed for cost and benefit criteria, not only there has not been enough attention for engineering design situations in which approaching the target values are desirable but also the available methods have shortcomings. A new version of VIKOR method, which covers all types of criteria with emphasize on compromise solution, is proposed in this paper. The proposed comprehensive version of VIKOR also overcomes the main error of traditional VIKOR by a simpler approach. Suggested method can enhance exactness of material selection results in different applications, especially in biomedical application where the implant materials should possess similar properties to those of human tissues. Five examples are included to illustrate and justify the suggested method.

Background Bones in human body are prone to damage due to different causes such as fractures, diseases, and infections. Nevertheless, they have a remarkable capacity to repair and heal themselves after trauma and illness. Large defects, however, are never completely reinstated because their sizes are beyond the limit up to which the bones can repair [1]. In these conditions, therefore, a medical remedy is required to stabilize, align and support the damaged bone region to restore the lost function. Bone autografts are considered the gold standard treatment. However, they have a number of shortcomings including the limited sources and donor site morbidity. Allografts also have the risk of immune rejection and disease transmission [2, 3]. Therefore, the research has headed for other solutions via tissue engineering. Bone tissue engineering provides three-dimensional (3D)

Large injuries to bones are still one of the most challenging musculoskeletal problems. Tissue engineering can combine stem cells, scaffold biomaterials, and biofactors to aid in resolving this complication. Therefore, this review aims to provide information on the recent advances made to utilize the potential of biomaterials for making bone scaffolds and the assisted stem cell therapy and use of biofactors for bone tissue engineering. The requirements and different types of biomaterials used for making scaffolds are reviewed. Furthermore, the importance of stem cells and biofactors (growth factors and extracellular vesicles) in bone regeneration and their use in bone scaffolds and the key findings are discussed. Lastly, some of the main obstacles in bone tissue engineering and future trends are highlighted.

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