# Clinical Case Employing Two Different Biomaterials in Bone Regeneration
## 2 Clinical Report  
### Case Description  
Our patient was a 59-year-old Caucasian woman, who was a nonsmoker and a nondrinker. Her medical history reported recurring abscessual episodes in regions 34-36, where a fixed prosthesis was present. Its pillars had exhibited several issues since 2010, as is visible in Figures 1 and 2. Indeed, it was possible to see a periapical lesion in Region 34, and peri-implantitis around the implant in Region 36. At the same time, there was also a radiolucent lesion at the apexes of regions 45 and 46. Over time, all lesions in the oral cavity were treated. Lastly, with the patient's agreement, the rehabilitation of Regions 34-36 was initiated, ending with prosthetic restoration. Initially, retreatment of Region 34 was performed since it presented a periapical lesion (which was already present in 2010). In May 2017, as the lesion was already significantly regressing, we proceeded to extract Region 35 and remove the implant at Region 36, since it had begun exhibiting pericoronitis in a large area. At the site where we extracted Region 35, we proceeded to implant xenohybrid graft SmartBone (SB), developed and manufactured by Industrie Biomediche Insubri SA (IBI-SA) via a proprietary process that improves the properties of naturally derived biomaterials [23]. SB was specifically developed for regenerative-medicine applications, and has a long track record of clinical applications [24; 25; 26; 27; 28]. SB is composed of a decellularized-bovine-bone matrix reinforced with bioresorbable aliphatic polyesters and RGD-containing collagen fragments [23; 29], where RGD is the tripeptide sequence ArginylGlycylAspartic acid that is the most common peptide motif responsible for cell adhesion to the extracellular matrix. SB was mixed with concentrated growth factors (CGFs; Medifuge MF200, Silfradent S.R.C., 47018 Santa Sofia FC, Italy) using a special technique that ensured a product richer in regeneration factors and easy to manipulate [30; 31]. In this region, recurring inflammatory episodes due to the longitudinal radicular fracture had caused considerable vestibular-cortical-bone loss, which was the reason for using a xenograft in this area. In Region 36, peri-implantitis had created a substantial bone-erosion cone, but had not caused much vestibular-cortical-bone loss, hence the decision to graft a calcium-phosphosilicate-based alloplastic material (NovaBone Dental Putty, Novabone, Jacksonville, FL USA). This was placed inside the remaining residual site after implant removal. Calcium phosphate derivatives provide less mechanical support than SB xenografts, as they have low resistance to tension, and during their degradation, their mechanical resistance is quickly reduced [20]. We knew from the scientific literature that, in septic cases, the best course of action is to operate on two different occasions separated by at least  
Figure 1: Rx Opt from 2010, taken when treating the patient. Figure 2: Cone-beam computed tomography (CBCT) analysis (Acteon X-Mind Trium) before surgical treatment showed severe impairment of Region 35 caused by radicular fracture and accentuated peri-implantitis around fixture in Region 36. (**A**) Curved planar reformation, and cross-sections of Regions (**B**) 35 and (**C**) 36. 40-60 days. However, we chose a more aggressive procedure, treating the bone sites with an antibiotic wash (RIFOCIN(r) rifamycin, Sanofi Aventis, Paris, France), and applying laser decontamination (Deka SmartFile Nd:YAG, DEKA, Calenzano, FI, Italy). We proceeded to apply the materials as previously described using a CGF membrane (Sifradent Medifuge MF200), and then sutured the trapezoidal flap with silk along its width, having previously sculpted the area through full-thickness skeletonization of the external mandibular cortex with respect to the neurovascular bundle emerging from the mental hole. This design allowed us to obtain a tissue cover for the graft from the periosteum in order to achieve the best revascularization possible.