Comparison of Autogenous Block Bone Graft and Screw Tent-Pole Techniques for Vertical Bone Augmentation in the Posterior Mandible: A Split-Mouth Randomized Controlled Study

Aim: To evaluate the effect on vertical bone augmentation of the screw tent-pole technique using particulate allograft in combination with injectable platelet-rich fibrin, and to compare this with autogenous block bone graft. Materials and Methods: This split-mouth randomized controlled study involved patients with bilateral partial edentulism and vertical bone loss in the posterior mandible. In each patient, the control side was treated with autogenous block bone graft harvested from the mandibular ramus and, on the test side, the screw tent-pole technique was employed, using particulate allograft in combination with injectable platelet-rich fibrin. All augmented sites were covered by leukocyte and platelet-rich fibrin membrane. The primary outcome variable of this study was the radiographic changes to bone height 6 months after augmentation. The secondary outcome variables were the percentage of newly formed bone and the implant survival rate. The data were analyzed with a significance level of α = 0.05. Results: Of the 13 patients included, a total of 11 patients (7 females, 4 males; mean age 50.92) completed the study. The mean values of vertical bone gain were 1.72 ± 0.78 mm for the test group and 2.83 ± 0.89 mm for the control group, which constitutes a significant difference ( P = .008). The percentage of newly formed bone was 18.08% ± 2.17% for the test group and 14.26% ± 1.76% for the control group. The difference between the groups was statistically significant ( P < .001). The implant survival rates were 100% for both study groups. Conclusions: Based on the study results, screw tent-pole can be considered a feasible technique for bone augmentation. Further randomized studies will be necessary to fully evaluate vertical bone augmentation using the screw tent-pole technique, with different graft materials and with larger samples.

High Potential of Bacterial Adhesion on Block Bone Graft Materials

Bone graft infections represent a challenge in daily clinics, resulting in increased patient discomfort and graft removal. The aim of this study was to investigate the initial adhesion of five representative pathogens on three different block bone graft materials (xenogeneic, alloplastic and allogeneic) and to assess if chlorhexidine (CHX) can effectively control the initial bacterial adhesion. Three different block bone grafting materials (Tutobone®, Endobon® and human spongiosa) were incubated with Escherichia coli, Staphylococcus aureus, Streptococcus mutans, Enterococcus faecalis and Pseudomonas aeruginosa in the presence or absence of 0.2% CHX solution. Bacterial adhesion was assessed by the direct counting of the colony-forming units (CFUs) and visualized by scanning electron microscopy (SEM). Overall, the selected bacterial species adhered successfully to all tested bone replacement scaffolds, which showed similar bacterial counts. The lg CFU values ranged from 5.29 ± 0.14 to 5.48 ± 0.72 for E. coli, from 4.37 ± 0.62 to 5.02 ± 0.48 for S. aureus, from 4.92 ± 0.34 to 4.95 ± 0.21 for S. mutans, from 4.97 ± 0.40 to 5.22 ± 0.13 for E. faecalis and from 4.23 ± 0.54 to 4.58 ± 0.26 for P. aeruginosa. CHX did not interfere with initial microbial adhesion, and yet it killed all adhered bacterial cells. Thus, CHX can be used to prevent subsequent biofilm infections.

Immediate Ridge Augmentation Using Autogenous Tooth Root as a Block Graft in a Periodontally Hopeless Extraction Site: A Pilot Study

The aim of the our study was to assess the efficacy of autogenous tooth root as block bone graft in reconstructing the vertical and horizontal dimensions at periodontally hopeless extraction sites both clinically and radiographically. Methods: A total of 13 patients having a tooth with periodontally hopeless prognosis indicated for extraction were included in the study. Following atraumatic extraction the tooth was processed to create a decoronated cementum free dentin block which was used to augment the extraction socket. Results: The augmentation of periodontally hopeless socket with tooth block autograft resulted in gain of clinical ridge width of 5.9mm radiographically, apico-coronal defect depth reduced upto 8.2 mm (p 0.001) and gain in ridge width of 5.8 mm post-operatively after 6 months (p 0.001). Conclusion: The present study demonstrated the effectiveness of using tooth root as a block graft for ridge augmentation in the periodontally hopeless extraction site making it suitable for implant placement in future.

Comparative Outcomes of Block and Cancellous Iliac Bone Grafting in Older Unilateral Alveolar Cleft Patients

Objective: To compare osseous outcomes of block and cancellous iliac bone grafting in older unilateral alveolar cleft patients. Design: Retrospective and observational follow-up study. Setting: Cleft Lip and Palate Centre, Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Stomatology, Nanjing Medical University, China. Patients: Forty-five nonsyndromic patients with unilateral complete alveolar cleft were enrolled in this study (25 patients in block bone graft group and 20 patients in cancellous bone graft group). Interventions: In cancellous bone graft group, the alveolar cleft was filled with iliac cancellous bone particulate. In group of block bone graft, the harvested bone block was trimmed and fixed in alveolar defect. Main Outcome Measures: A novel method was proposed to investigate the volume and density of residual bone graft at 1-week, 3- and 6-month, 1- and 2-year postoperatively based on cone beam computed tomography scans. Results: No difference in bone graft volume was found between 2 groups at 1-week and 3-month postoperatively; however, the residual volume of block bone graft group was significantly larger than that of cancellous bone graft group at 6-month, 1- and 2-year postoperatively. The bone density of block bone graft group was lower at 1-week and 3-month postoperatively but was comparable at 6-month, 1- and 2-year postoperatively. Our method was reliable and accurate to identify the range of residual bone graft when the boundary of grafted bone could not be identified clearly. Conclusion: Block bone graft could achieve comparable bone density and retain a greater amount of residual bone comparing to cancellous bone graft.

Sandwich Osteotomy With Interposition Of A Bovine Block Bone Graft for Vertical Ridge Augmentation

The aim of the present study was to report the clinical case of a patient with a vertical defect of the alveolar ridge, which prevented the installation of dental implants without first treating the defect in question. A 32-year old female patient with a height defect of approximately 6 mm in the region of the missing absent teeth (13 and 14). The patient was treated using the sandwich osteotomy technique, with the interposition of a block bone graft of bovine origin. No complications were reported in the post- operative period. After seven months, two dental implants were installed in the relevant region. The bovine bone graft was incorporated into the relevant area. The bovine bone block graft used in this clinical case was shown to be a viable option for interposition between bone segments that have been osteotomized via sandwich osteotomy.

Considerations On The Use Of Xenogenous Bone Blocks In Implantology: A Case Report

In implantology, an increase in the bone thickness of the alveolar ridge is often associated with the use of autogenous bone, which is considered to be the gold standard. The aim of the present study was to report the clinical case of a patient with abnormal bone thickness in the alveolar ridge, causing severe esthetical damage, and the use of xenogeneic block bone grafts. A female, 43-year old patient exhibited a considerable bone defect in the region of teeth 11 (absent), although there was sufficient native bone available for the implantation. The patients treatment involved positioning the implant and performing a block bone graft using bone of bovine origin. The post-operative period passed without complications. The post-operative clinical examination confirmed the correction of the pre-existing esthetic defect and the health of the soft tissues involved. The tomographic examination 180 days post-surgery also confirmed an excellent increase in thickness. The bovine block bone graft used in the present case was shown to be viable in terms of correcting esthetic defects when there is sufficient native bone available for the implantation.