A 4 mm-Long Implant Rehabilitation in the Posterior Maxilla with Dynamic Navigation Technology: A Case Report after a Three-Years Post-Loading Follow-Up.

The use of short (<8 mm long) and ultra-short (<6 mm long) implants allows the prosthetic rehabilitation of the posterior ridges of the jaws avoiding reconstructive procedures. Nevertheless, this approach requires vast experience to ensure the primary stability of the fixture in a correct position. Computer-aided implantology (CAI) achieves better results than the free-hand one in terms of placement accuracy, reducing the surgical risks and the operative timings. Dynamic navigation (DN) allows the surgeon to track the position and movements of the drill in real-time on the CT imaging data set. It is more versatile than the computed static system, enabling the operator to change the guidance coordinates according to the intra-operative feedbacks. A mono-edentulous upper right first molar site was rehabilitated with a four mm-long implant to avoid reconstructive techniques, drastically rejected by the patients. The case was managed within a DN protocol considering the minimal available bone and the prosthetic demands. The phases of this procedure were strictly documented up to a 3-year follow-up. No intra-operative problems occurred, and adequate primary stability of the implant was obtained. The prosthetic loading was carried out within only six weeks without any complications. No variation of the baseline clinical scenario as evidenced clinically and radiographically at the end of follow-up. No similar cases are reported in the literature.

Two-Year Follow-Up of 4-mm-Long Implants Used as Distal Support of Full-Arch FDPs Compared to 10-mm Implants Installed after Sinus Floor Elevation. A Randomized Clinical Trial.

BACKGROUND: In edentulous patients, bone resorption cannot allow the installation of standard implants and it is demanded to use short implants in the residual alveolar bone or longer implants in grafted bone. AIM: To compare the survival and bone level changes of standard plus short 4-mm implants used as distal support of a maxillary full-arch fixed dental prostheses (FDPs) with standard (10-mm) implants placed in association with a bilateral sinus floor augmentation procedure. MATERIAL AND METHODS: Full-arch FDPs supported by six implants were randomly placed in both groups. In the control group, all implants were 10 mm long and 4.1 mm in diameter. The distal implant in both sides of the maxilla was installed after 4 months from bilaterally sinus floor elevation. In the test group (short group), the distal implant in both sides of the maxilla was 4 mm long and 4.1 mm in diameter. No sinus floor elevations were performed in the test group. Clinical assessments and X-rays were taken at prosthesis delivering and after 6, 12, 18, and 24 months. Patient-reported outcome measures (PROMs) were also evaluated before surgery and after 6, 12, and 24 months. RESULTS: The changes over time of the bone level for the short implants were -0.01 ± 0.11 mm, -0.04 ± 0.13 mm, -0.17 ± 0.29 mm, and -0.28 ± 0.37 mm after 6, 12, 18, and 24 months from prosthesis delivering, respectively. For the standard implants, bone changes were -0.21 ± 0.33 mm (p = 0.103), -0.30 ± 0.32 mm (p = 0.023), -0.40 ± 0.37 mm (p = 0.144), and -0.54 ± 0.49 mm (p = 0.128), respectively. A statistically relevant difference was found only at 12 months after loading between the two groups. CONCLUSIONS: Similar results on implant survival rate and marginal bone loss were observed for the short and standard implants, placed in association with a bilateral sinus floor augmentation procedure, used as distal support of a maxillary full-arch FDP. A statistically relevant difference was found only at 12 months after loading between the two groups (p = 0.023).

Inferior alveolar nerve laceration after implant site preparation: A case report.

PURPOSE: The aim of this article is to present a referred clinical case of an inferior alveolar nerve laceration during the insertion of a dental implant in the mandible, that came to our attention after the injury. MATERIALS AND METHODS: A 71-year-old female was treated by a colleague in order to be rehabilitated with a fixed implant-supported prosthesis for her missing teeth in positions 44, 45 and 46. After implant site osteotomy in region 46, the speed of the surgical motor was not changed; as a consequence, the implant was inserted at 1200 rpm and intruded into the mandibular canal, causing the laceration of the neurovascular bundle. RESULTS: During the first 2 weeks after surgery the patient complained of paresthesia in the mental and lower lip area, with labial ptosis and drooling. After 14 days, the paresthesia reduced and mucosal and gingival normosensitivity was detected; however, the patient complained about hyperesthesia of the lower inside lip. After 21 days, the lower lip tone and function were almost completely restored and the paresthesia was further reduced, however the hyperesthesia persisted. CONCLUSIONS: It is extremely important to pay attention to preventing neurological complications through proper preoperative planning, careful execution of the surgical techniques and correct management of instruments and motor speed settings. The latter procedure should be double-checked by both the operator and the assistant.