*4.2. Patient No. 2*

A 52-year-old man with no known allergies or medical or toxicological history of interest came to the clinic to assess the extraction of the 15 root remnant (Figure 5A) and placement of an implant. The case was assessed and, as there was not enough apical bone (Figure 6A), the possibility of placing an implant immediately after extraction was ruled out; it was decided to perform alveolar preservation after extraction and placement of the implant in a second surgical phase. We proceeded to the extraction of 15 and alveolar preservation with Bond Apatite® according to the manufacturer's protocol, extraction, curettage of the alveolus, placement of a Bond Apatite® syringe, compression with dry and sterile gauze, coverage with a collagen sponge and point of cross suture (Figure 7). There were no intraoperative complications. The recommendations and postoperative pharmacological guidelines were delivered. A week later, the patient attended suture removal reporting considerable pain. On examination, alveolitis and loss of graft material were observed, so the medication was changed to Amoxicillin/Clavulanic Acid 875/125 mg every 8 h × 7 days, Dexketoprofen 25mg every 8 h alternated with Metamizole 575 mg every 8 h if there was pain. Periodic monthly follow-ups were carried out (Figure 5B,C) and at 4 months a new CBCT of the area was requested (Figure 6B) for implant planning, where good healing and maintenance of bone volume were observed. On the day of surgery, a trephine biopsy was taken in the regenerated area for histopathological analysis (Figure 8) and a 3.5 × 10 mm Microdent® Genius implant was placed following the milling protocol of the commercial house (Figure 5D). The same pharmacological regimen was prescribed as on the day of the extraction and monthly follow-up visits were scheduled. Currently, he must undergo the second surgical phase and subsequent prosthodontic rehabilitation.

**Figure 5.** (**A**) Immediate postoperative periapical; (**B**) One week IOPA; (**C**) One month IOPA; (**D**) Two months IOPA; (**E**) IOPA after implant placement.

**Figure 6.** (**A**) Previous CBCT; (**B**) CBCT after 4 months.

**Figure 7.** (**A**) Preoperative occlusal view; (**B**) Dental extraction of 25; (**C**) Placement of Bond Apatite®; (**D**) Postoperative occlusal view; (**E**) One-week follow-up.

**Figure 8.** (**A**) Remains of inorganic material with newly formed bone trabeculae in (**A**) at 50× and in (**B**) at 200×. Total bone length of 5.97 mm and newformed bone of 2.98 mm.

## *4.3. Patient No. 3*

A 61-year-old male with no known allergies or relevant medical or toxicological history presented with pain in 24. He had a 24 endodontic treatment, with a filtered metal-ceramic crown in the distal part, non-restorable caries, so extraction was decided (Figure 9A). A CBCT was requested to assess the possibility of immediate implant placement, but the option was ruled out due to the presence of an apical lesion (Figure 10A). It was decided to perform alveolar preservation after extraction and placement of the implant in a second surgical phase. We proceeded to extract 24, profuse curettage of the alveolus, placement of a Bond Apatite® syringe, compression with dry and sterile gauze, and instead of placing a collagen sponge, the manufacturer's protocol was slightly changed since the closure was carried out by primary intention using a vestibular mucoperiosteal flap (Figure 11). There were no intraoperative complications. The recommendations and postoperative pharmacological guidelines were delivered. The stitches were removed a week after surgery and regular monthly check-ups were performed (Figure 9B–E). At 4 months, a new CBCT of the area was requested for implant planning, where good healing and maintenance of bone volume were observed (Figure 10C). On the day of surgery, a trephine biopsy was taken in the regenerated area for histopathological analysis (Figure 12) and a 3.5 × 12 mm

Microdent® Genius implant was placed following the milling protocol of the commercial house (Figure 9F). The same pharmacological regimen was prescribed as on the day of the extraction and monthly follow-up visits were scheduled. Four months after the placement of the implant, the second surgical phase was performed and at the time of removal of the closure plug, the implant was explanted in its entirety, showing the lack of osseointegration of it, a profuse curettage of the area and the implant replacement visit was scheduled after 3 months.

**Figure 9.** (**A**) Preoperative IOPA; (**B**) Immediate postoperative IOPA; (**C**) One week IOPA; (**D**) One month IOPA; (**E**) Two months IOPA; (**F**) IOPA after implant placement.

**Figure 10.** (**A**) Previous CBCT; (**B**) Immediate postoperative CBCT; (**C**) Postoperative CBCT after 4 months.

**Figure 11.** (**A**) Preoperative occlusal view; (**B**) Dental extraction of 24; (**C**) Mucoperiosteal flap; (**D**) Passivity check; (**E**) Placement of Bond Apatite®; (**F**) Closing by the first intention; (**G**) Oneweek follow-up.

**Figure 12.** Remains of inorganic material and abundant newformed bone. Some degree of spinal cord fibrosis. (**A**) at 50× and (**B**) at 200×.Total bone length is 4.7 mm and newformed bone is 2.34 mm.
