# Microstructural Evaluation of Dental Implant Success Using Micro-CT: A Comprehensive Review
## 7 Micro-CT in Biomaterial Evaluation and Bone Augmentation  
In circumstances where bone damage has been incurred as a result of trauma or disease, a bone graft is typically employed as a replacement. The bone graft utilized is typically derived from the patient's own bone tissue (autogenous) or can be procured from alternative sources, including bovine bone, allogenic bone, and hydroxyapatite. The use of autogenous bone is the optimal choice, but there are several disadvantages, including the necessity for additional surgical procedures, the risk of infection, and postoperative discomfort. Consequently, the use of allogenic and xenogeneic bone as bone substitutes is a prevalent practice [78].  
The structural characterization of biomaterials is a crucial aspect in the investigation of the properties of bone substitutes prior to implantation and the selection of biomaterials for specific clinical applications. Porosity represents a crucial factor in the development of bone tissue engineering scaffolds, as it facilitates the invasion of progenitor cells. A high degree of porosity will facilitate the migration of mesenchymal and osteoblast cells to the recipient site. Pores between 100 and 300 \(\upmu\)m are necessary to facilitate osteogenesis; however, larger pores may compromise the mechanical strength of the material. The results of preclinical micro-tomography analysis indicate that biomaterials derived from cattle and horses exhibit a greater resemblance to human bone than other materials [79].  
The characteristics of porosity and pore size influence the surface area per volume. A high degree of porosity is conducive to the diffusion of nutrients, the transport of waste products, the formation of new blood vessels, and the growth of tissue. The control of porosity is of significance for all applications, given its impact on the mechanical properties of the material in question. The characterization of the microstructure is of great importance with regard to the performance of scaffolds. In this context, micro-CT represents a valuable instrument for the aforementioned purpose [80].  
[PERSON] et al. (2020) conducted research related to bone augmentation in dental implants. In this study, [PERSON] examined three types of bone material utilized for augmentation: auto-genous bone, allogenic bone, and artificial bone (bone substitute material). The micro-CT analysis conducted at weeks 4 and 12 yielded the following results: the bones derived from artificial bone exhibited higher values for BV/TV and bone mineral density (BMD) when compared to those derived from autogenous bone and allogenic bone. Furthermore, in Tb. Th, significant change was observed in the three groups. The Tb. N from the artificial bone group exhibited a significantly higher value compared to the autogenous and allogenic bone groups. With regard to Tb. Sp, the value of the artificial bone group was found to be relatively lower than that of the autogenous and allogenic bone groups. This suggests that the artificial bone group exhibits a more comprehensive repair process [81].  
Recent studies have employed micro-CT analysis to evaluate various bone augmentation techniques. [PERSON] et al. (2020) discovered a positive correlation between CBCT and micro-CT data, indicating the potential of CBCT for the analysis of bone microarchitecture in augmented sinuses [82]. In a recent study, [PERSON] et al. (2024) developed a novel volumetric micro-CT analysis to quantify new bone formation in rabbit calvarias. Their findings revealed a notable decline in bone formation from the outer to the inner regions across the grafting material [83]. In their 2020 study, [PERSON] and colleagues employed micro-CT to evaluate bone replacement scaffolds in human subjects. They analyzed morphological parameters, including porosity, bone volume fraction, and trabecular thickness,to assess biomaterial properties and their impact on bone regeneration [79]. These studies underscore the value of micro-CT in evaluating bone augmentation techniques and biomaterial efficacy.