# Allogeneicic Demineralized Dentin Matrix Graft for Guided Bone Regeneration in Dental Implants
## 4 Discussion
However, we did not measure the thickness of the remaining BMB before GBR because the resorbing buccal marginal bone was trimmed to at least 0.5 mm thickness or more. Regarding the maxilla and mandible, maxillary BMB height showed more resorption than that of the mandible during both the initial and functional periods. However, [PERSON] et al. reported that implants placed in the maxilla showed less bone loss than implants placed in the mandible after 1-year loading [35]. This result suggests that there are differences in remodeling procedures after GBR between the maxilla and mandible, and there may be greater volumetric shrinkage in the maxilla than in the mandible. The BMB resorption in CBCT was associated with a remodeling process rather than inflammatory destruction of the cortical bone around the implant neck [9]. Both in the maxilla and mandible, the BMB was less mineralized and mature before prosthetic loading. Twelve months after prosthetic loading, the BMB showed sound cortico-cancellous bone complexes surrounding the implant neck area without inflammatory destruction of the cortical bone. Therefore, the BMB resorption in this study was commensurate with the remodeling process rather than inflammatory bone resorption [36]. There have been previous concerns regarding the antigenicity of Allo-DDM in clinical applications. In the 1970s, several animal studies investigating the antigenicity of Allo-DDM showed a negligible inflammatory reaction. Therefore, the immune response to the first set of demineralized and lyophilized allogeneic dentin implants did not prevent bone induction [15; 16]. In 1983, [PERSON] examined the prevalence of allogeneic immune reactions elicited by implantation of allogeneic dentin using a blood test and reported no correlation between the incidence of immune reactions and the clinical or radiographic course of treatment. Moreover, there was a feeble correlation between the immune reaction and the HLA- or ABO-matched grades [37]. [PERSON] et al. [38] and [PERSON] et al. [39] reported that the use of Allo-DDM was biocompatible with the process of bone repair and showed excellent rates of graft acceptance in rabbits treated with Allo-DDM. [PERSON] et al., however, reported very similar results to those of Auto-DDM in qualitative and histological observations [20]. Although we obtained only one sample each Auto-DDM and Allo-DDM graft, histological findings presented excellent biocompatibility and satisfactory bone formation and remodeling, which corresponded to previous clinical reports of Auto- and Allo-DDM in 2016 [9; 36]. In 2017, [PERSON] et al. [21] reported that the occasional immunizing effects of Allo-DDM did not contraindicate future clinical applications in humans. The allogeneic applications of human DDM have several differences when compared with demineralized freeze-dried bone (DFDB), which has been extensively used in alveolar bone augmentation since 1980s [40] with a risk of transmission of viral diseases such as HIV, HBV, HCV, and venereal diseases such as syphilis. Foremost, dentin is a cell-free matrix without blood vessels, while bone includes osteocytes and blood vessels, which are the principal carriers of viruses and antigenicity [41; 42]. Additionally, DFDB is collected from the deceased, while DDM can be legally procured and collected from patients during dental treatment. Therefore, the risk of infection and transmissible viral diseases can be significantly reduced with the application of DDM [23; 42]. Furthermore, demineralization has been confirmed as a viral inactivation method and is used by many tissue banks to validate viral clearance for DFDB [43; 44]. Additionally, the demineralization of dentin can be a potent viral inactivation method for DDM [23]. Thus, the use of Allo-DDM has resolved the issues of antigenicity and reduced the risk of transmissible viral diseases [23; 43; 44]. This clinical pilot study had several limitations.