Medicine by Alexandros G. Sfakianakis,Αλέξανδρος Γ. Σφακιανάκης

Long-Term Outcomes of Tooth-Implant-Supported Rehabilitation of Periodontally Compromised and Treated Patients Refusing Bone Grafting Surgical Therapies

Objective: To evaluate the long-term incidence of complications in abutment teeth and dental implants in periodontally treated and maintained patients, refusing bone grafting surgical therapies, rehabilitated with full-arch telescopic-retained retrievable prostheses (TRPs) and full-arch fixed prosthesis (FPs), both supported by teeth-implants combination. Materials and Methods: After active periodontal therapy, 18 patients were rehabilitated with full-arch TRPs, whereas 17 patients were rehabilitated with full-arch FPs. Patients were annually evaluated for technical and/or biological failures/complications. Results: During the 15-year observation period, 6 of 164 (3.6%) implants failed and 19 of 233 teeth were extracted (9.2%) in the TRPs group, whereas 6 of 152 (3.9%) implants failed and 23 of 221 (10.4%) abutment teeth were extracted in the FPs group. Differences in implant failures and abutment teeth loss between the 2 groups were not statistically significant. In both the groups, Cox regressions identified significant difference (P < 0.05) for mean initial bone loss, aggressive periodontitis, and smoking, as factors contributing to tooth loss and implant failures in general. Conclusion: In periodontally treated patients, refusing bone grafting surgical therapies, rehabilitated with full-arch TRPs and full-arch fixed prostheses, both supported by teeth-implants connection, high survival rates can be expected if regular supportive periodontal therapy had been performed.

Sinus Floor Elevation and Antrostomy Healing: A Histomorphometric Clinical Study in Humans

Objectives: To compare the histomorphometric outcomes of biopsies collected from the antrostomy and from the alveolar crest of the maxillary sinus after a sinus-lift procedure. Material and Methods: In 12 volunteers, sinus floor elevation was performed using collagenated corticocancellous porcine bone. Nine months after the surgery, 2 biopsies, 1 from the alveolar crest and 1 from the antrostomy, were collected for histological analysis. Results: Biopsies from 11 patients were available for histological analyses (n = 11). At the alveolar crest sites, the percentage of mineralized bone was 40.1 ± 14.1%, of bone marrow was 40.1 ± 18.0%, and of the xenograft was 14.7 ± 15.2%. Small amounts of soft tissue were found. At the antrostomy sites, the percentages of mineralized bone, bone marrow, and xenograft were 26.0 ± 10.8%, 23.4 ± 17.0%, and 28.2 ± 15.7%, respectively. Soft tissue was represented by 19.7 ± 19.4%. Conclusion: Higher amounts of mineralized bone and bone marrow were found in the alveolar crest compared with the antrostomy.

Evaluation of Risk Parameters in Bone Regeneration Using a Customized Titanium Mesh: Results of a Clinical Study

Purpose: The aim of the study was an evaluation of risk factors for an innovative bone regeneration technique using a customized titanium mesh that was tested in a clinical setting. Materials and Methods: This retrospective study included 65 patients with 70 grafting procedures of osseous defects of the jaws with a customized titanium mesh together with Advanced- and Injectable-Platelet-Rich Fibrin (A- and I-PRF), resorbable membranes, and bone grafting materials. Exposures of the meshes and grafting outcome were analyzed according to a novel classification as (a) punctual and (b) tooth width or complete exposure of the mesh (c). No exposure was stated as (d). Results: In 37% of cases, exposures of the meshes occurred that were significantly associated with loss of grafted material (P < 0.001). Tobacco abuse (P = 0.032) and grafting procedures together with simultaneous sinus floor elevation techniques (P = 0.001) were found to be risk factors for success of the grafted material. Implant placement was not possible in 2 cases only. Conclusion: The results of this study verified the treatment of large defects with a customized titanium mesh as a useful protocol with a predictable outcome, even in cases of dehiscences.

Fifteen-Year Follow-up of Short Dental Implants in the Completely Edentulous Jaw: Submerged Versus Nonsubmerged Healing

Purpose: Short implants are a minimally invasive alternative in the management of alveolar bone atrophy. This study aimed to assess the influence of the surgical approach (1-stage vs 2-stage) on the 15-year survival and marginal bone loss of short implants in a fixed complete denture. Materials and Methods: A retrospective clinical study was conducted in a single private dental clinic that included short implants placed between January 2001 and December 2002. Results: Forty-one short implants supported 18 screw-retained complete dentures. The mean follow-up time was 15 ± 3 years. The surgical approach (1-stage vs 2-stage) did not significantly affect implant survival and marginal bone loss. The implant survival rate was 90.2%. Conclusions: Short dental implants could be predictably indicated to support fixed complete dentures. The implants could be placed through a 1- or 2-stage surgery.

Accuracy of Computer-Guided Template-Based Implant Surgery: A Computed Tomography–Based Clinical Follow-Up Study

Objective: The aim of this clinical study was to analyze the accuracy of computer-guided implant surgery. Materials and Methods: Assisted by computed tomography (CT)-based planning software and navigational templates, 16 patients successfully received 26 dental implants. Each implant parameter (a–d) was calculated based on superimposed preoperative and postoperative cone beam CT scans: (a) deviation at entry point; (b) deviation at apex; (c) angular deviation; and (d) depth deviation. Results: Mean central deviation at implant entry point and apex was 0.91 mm (standard error [SE] = 0.11 mm; 95% confidence interval [CI]: 0.69–1.13) and 1.22 mm (SE = 0.11 mm; 95% CI: 0.99–1.45), respectively. Mean angulation deviation was 4.11 degrees (SE = 0.52 degrees; 95% CI: 3.04–5.17) and the average depth deviation was 0.65 mm (SE = 0.11 mm; 95% CI: 0.42–0.87). For the total number of implants placed, the maximum error was 2.34 mm at entry point, 2.71 mm at apex, 9.44 degrees in angular deviation, and 2.00 mm in depth deviation. Conclusion: Great accuracy was reached even in advanced cases with prior bone augmentation and complex traumas. This leads to the conclusion that particularly in advanced cases, computer-guided implantation can be beneficial.

Chemical Stability and Antimicrobial Activity of Plasma-Sprayed Cerium Oxide–Incorporated Calcium Silicate Coating in Dental Implants

Purpose: The aim of this study is to investigate the biological activity and antibacterial property of cerium oxide–incorporated calcium silicate coatings (CeO2-CS) in dental implants. Materials and Methods: In this study, MC3T3-E1 cells cultured on the plastic, Ti-6Al-4V, and the cerium oxide–incorporated calcium silicate coatings (CeO2-CS) coating served as the blank, control, and CeO2-CS groups, respectively. A cell counting kit-8 (CCK-8) and flow cytometry were used to evaluate the biocompatibility. The osteoblastic differentiation of the MC3T3-E1 cells was also analyzed by quantitative real-time polymerase chain reaction analysis. The CCK-8 and counts of colony-forming units (CFUs) were used to detect the antibacterial activity of the coating on Enterococcus faecalis. The study showed that the cerium oxide–incorporated calcium silicate coating (CeO2-CS) has better biocompatibility. Meanwhile, the ALP, OCN, and BSP mRNA expression levels in the CeO2-CS group were significantly upregulated (P < 0.05). The number of viable bacteria and the CFU results were significantly reduced in the CeO2-CS group (P < 0.05). Conclusion: The cerium oxide–incorporated calcium silicate coatings (CeO2-CS) may promote the osteoblastic differentiation of osteoblasts. Meanwhile, the cerium oxide–incorporated calcium silicate coating (CeO2-CS) showed strong antimicrobial activity on E. faecalis, with good biocompatibility.