## 4 Discussion
However, the literature reveals successful cases [8; 9; 16], suggesting it is a safe technique with over 6 years of follow-up [16]. Furthermore, the results show no difference in the pro-inflammatory cytokine between the types of treatment in immunoassay. The increase in IL-18 is indicative of delayed healing [26], although this cytokine decreased during the healing periods. Besides the uneventful healing with no infection, maintaining the biomaterial in the grafted site is critical. A diligent follow-up with rigorous postoperative instruction is required, and it was reinforced at the recall visits during sample collections. Another concern about exposing the DBBM to the oral environment is maintaining the material in position during the healing phases. Based on the follow-up tomography performed at 4 months postoperatively, where the presence of xenogeneic bone particles was clearly visible, it is possible to verify that the biomaterial was kept in place. Additionally, this finding is supported by the results of the horizontal and vertical linear bone measurements taken at 4 months, which were similar in both the exposed group and the group that used collagen matrix to seal the wound, suggesting that the bone was well maintained, comparable to the control group. The grafted sites with the DBBM and membrane exhibited a superior band of KM compared to non-grafted sites [19]. A collagen matrix can speed up the initial phases of soft tissue healing and potentially result in increased soft tissue thickness [2]. Recovery was faster in the BM group, with almost complete healing achieved in 7 days, whereas in the B group, this outcome was seen after 7 days. Considering the healing time, it is possible to justify why in the maxilla, the width of keratinized gingiva was notably higher in the BM group (3.42 \(\pm\) 0.36 mm) compared to the B group (2.00 \(\pm\) 0.31 mm) during the baseline to 1-2 months post-implant placement variation period (_p_ < 0.05). In the earlier assessment, the B group was still in a slower maturation phase, resulting in this difference, whereas in a longer evaluation period, from baseline variation due to gingival conditioning, the B group already has a greater width of keratinized gingiva. A KM width measuring under 2 mm was significantly associated with discomfort during brushing, a predisposition for the development of peri-implantitis, and a reduction in vestibular depth [13; 14]. It is important to emphasize the significance of the extension of this band and to highlight that in both study groups, there was an increase in KM compared to baseline. The DBBM could potentially enhance the soft tissue appearance over time, potentially attributed to the integration of particles into the soft tissue, mitigating bone loss and consequently leading to enhanced long-term esthetics [27]. Upon exposure of the DBBM to the oral cavity, the mucosal tissue that was formed is very similar to KM, suggesting a potential increase in this type of mucosa [16]. This may potentially justify the significant difference in a greater width of KM in the \(\Delta\) 1 to 2 months postoperative provisional contour in B when compared to BM (_p_ = 0.006). One of the limitations of this study was the potential influence of metal artifacts from the crown and the implant in the CBCT images could impact the results [28], potentially leading to inaccuracies in the measurements. Therefore, we chose not to perform soft tissue measurements due to the radiopacity of the implant and biomaterial in the gap. Future studies should focus on soft tissue measurements and further investigation into the histological characteristics of the tissue to deepen the understanding of these outcomes. Another limitation we must emphasize is the reliability of the assessment being constrained by the fact that the measurements were conducted by a single researcher. Furthermore, the results should be interpreted with caution, as despite the sample size calculations, the number of patients included is small and may not be sufficient to draw robust conclusions.