ABSTRACT
BACKGROUND: Mesenchymal stem cell (MSC) therapy gained interest among scientists following the discovery of its therapeutic potential. However, their clinical use has been hindered due to their immunogenicity and tumorigenicity. Relatively recently, it has been unveiled that the mechanism by which MSC promote healing is by secreting exosomes. This raised the interest in developing cell-free therapy, avoiding the obstacles that deterred the translation of MSC therapy into clinical practice. REVIEW: This comprehensive narrative review summarises the current understanding of exosome biogenesis and content. Moreover, the existing research on exosome use in bone tissue engineering is discussed. CONCLUSIONS: Exosome-based therapy may provide excellent potential in the field of bone tissue engineering and craniofacial reconstructive surgery. Further investigation is required before the technology can be translated into clinical practice.
ABSTRACT
BACKGROUND: Bone grafting has been considered the gold standard for hard tissue reconstructive surgery and is widely used for large mandibular defect reconstruction. However, the midface encompasses delicate structures that are surrounded by a complex bone architecture, which makes bone grafting using traditional methods very challenging. Three-dimensional (3D) bioprinting is a developing technology that is derived from the evolution of additive manufacturing. It enables precise development of a scaffold from different available biomaterials that mimic the shape, size, and dimension of a defect without relying only on the surgeon's skills and capabilities, and subsequently, may enhance surgical outcomes and, in turn, patient satisfaction and quality of life. REVIEW: This review summarizes different biomaterial classes that can be used in 3D bioprinters as bioinks to fabricate bone scaffolds, including polymers, bioceramics, and composites. It also describes the advantages and limitations of the three currently used 3D bioprinting technologies: inkjet bioprinting, micro-extrusion, and laser-assisted bioprinting. CONCLUSIONS: Although 3D bioprinting technology is still in its infancy and requires further development and optimization both in biomaterials and techniques, it offers great promise and potential for facial reconstruction with improved outcome.
ABSTRACT
BACKGROUND: Ethnic differences in craniofacial dimensions and proportional relationships means that ethnicity-specific data is required for both diagnosis and treatment planning. This investigation establishes normative craniofacial anthropometric values for the Sudanese female (SF) population, compares with North American White (NAW) and African-American females (AA), and analyses the occurrence of neoclassical norms within the study sample. METHODS: Standardized frontal and profile facial photographs were taken of 100 female participants. Five vertical and five horizontal anthropometric measurements were determined. RESULTS: Significant differences were found between the 3 populations. The sample showed very poor compliance with the neoclassical norms. The upper face height of the SF was â¼ 20-mm taller than the AA faces (p < 0.001). Midface, nasal and lower face heights were also significantly taller, by 15-mm, 10-mm and 10-mm respectively (p < 0.001). SF showed significant reduction in bizygomatic width (â¼ 30-mm), compared to NAW and AA (p < 0.001). Eye width was â¼ 5-mm less than the AA sample and 3-mm less than the NAW sample (p < 0.001). Mouth width was â¼ 5-mm less in SF than the other two groups (p < 0.001). The SF exhibited a reduced interalar width compared with AA (p < 0.001), but wider than the NAW (p < 0.001). CONCLUSIONS: The average SF face is significantly taller and narrower than the AA or NAW female face. The neoclassical proportional norms appear to be unreliable guides in relation to the SF face, and should not be used in comparative diagnosis and treatment planning. Use of the normative anthropometric data presented in this article, both linear and proportional values, should be considered in the diagnosis and treatment planning of young adult female patients of Sudanese descent.
