The medical history of this 48-year-old male patient showed a high blood pressure; otherwise, the patient was healthy. A successfully completed periodontal therapy was done before implant therapy. The patient demonstrated stable marginal bone levels. Autologous retromolar bone grafting using local anesthesia was performed in the left mandible (see Fig. 1a). This patient received a postoperative oral antibiotic therapy with amoxicillin 750 mg for 3 days. Three months after grafting two implants (Straumann, bone level) were placed in regions 36 and 37 (implant characteristic, see Table 1). During implant placement, cortical bone profiling was performed as recommended by the manufacturer guidelines. The bone graft appeared fully revascularized and incorporated. One day postoperatively the patient reported to have pain. The radiograph performed on that day demonstrated veritable inserted Straumann bone level implants. A peri-implant osteolysis was not visible (Fig. 1b). After 3 days of continuous severe pain, both implants were removed. At the time point of explantation, the local soft tissue showed no signs of inflammation. During surgical removal of the implants, an extensive osteolysis surrounding the implants was found and a thorough debridement of the area with a complete wound closure was performed. A second implant surgery was scheduled after 6 months with placement of two implants (Straumann, tissue level) in regions 36 and 37 (Fig. 1c). At reentry, the mandible appeared well vascularized; no granulation tissue was detectable. The drilling protocol was performed as recommended by the manufacturer including a cortical bone profiling before implant placement. Again after 3 days, both implants had to be removed because of continuous severe pain in the absence of any sign of soft tissue inflammation, swelling, or abscess formation.

At this time point, a screening of the relevant parameters for bone metabolism was performed and a vitamin D deficiency (vitamin D serum level 11 μg/l) was diagnosed. After vitamin D supplementation and a healing period of 6 months, a third surgical intervention was planned and one implant (Conelog ScrewLine) was inserted in region 36 (see Table 1 and Fig. 1d). During implant placement, the former explantation site appeared clinically fully re-ossified. The patient received an intraoperative intravenous single-dose antibiotic therapy with Isocillin 1.2 mega. At this time point, the patient demonstrated a vitamin D level of 46 μg/l. Second-stage surgery was successfully performed and the prosthetic restoration initiated. For all implants, a primary stability had been achieved.