André Antonio Pelegrine

Clinical and histomorphometric evaluation of extraction sockets treated with an autologous bone marrow graft.

PURPOSE The aim of this study was to evaluate the potential of an autologous bone marrow graft in preserving the alveolar ridges following tooth extraction. MATERIALS Thirteen patients requiring extractions of 30 upper anterior teeth were enrolled in this study. They were randomized into two groups: seven patients with 15 teeth to be extracted in the test group and six patients with 15 teeth to be extracted in the control group. Hematologists collected 5 ml of bone marrow from the iliac crest of the patients in the test group immediately before the extractions. Following tooth extraction and elevation of a buccal full-thickness flap, titanium screws were positioned throughout the buccal to the lingual plate and were used as reference points for measurement purposes. The sockets were grafted with an autologous bone marrow in the test sites and nothing was grafted in the control sites. After 6 months, the sites were re-opened and bone loss measurements for thickness and height were taken. Additionally, before implant placement, bone cores were harvested and prepared for histologic and histomorphometric evaluation. RESULTS The test group showed better results (P<0.05) in preserving alveolar ridges for thickness, with 1.14+/-0.87 mm (median 1) of bone loss, compared with the control group, which had 2.46+/-0.4 mm (median 2.5) of bone loss. The height of bone loss on the buccal plate was also greater in the control group than in the test group (P<0.05), 1.17+/-0.26 mm (median 1) and 0.62+0.51 (median 0.5), respectively. In five locations in the control group, expansion or bone grafting complementary procedures were required to install implants while these procedures were not required for any of the locations in the test group. The histomorphometric analysis showed similar amounts of mineralized bone in both the control and the test groups, 42.87+/-11.33% (median 43.75%) and 45.47+/-7.21% (median 45%), respectively. CONCLUSION These findings suggest that the autologous bone marrow graft can contribute to alveolar bone repair after tooth extraction.

Xenograft Enriched with Autologous Bone Marrow in Inlay Reconstructions: A Tomographic and Histomorphometric Study in Rabbit Calvaria

Objective. The aim of this study was to evaluate the bone healing after the usage of a scaffold enriched with bone marrow. Study Design. Ten rabbits were divided into 2 groups of 5 animals. Bilateral 12 mm diameter defects were created in the parietal bones. In control group Bio-Oss were inserted in both defects and, in experimental group, Bio-Oss enriched with autologous bone marrow were inserted in both defects. In these two groups, one of the calvarial defects was covered with Bio-Gide. The rabbits were sacrified 8 weeks after surgery and both CT and histomorphometric analysis were done. Results. The CT showed a lower remaining defect area in the experimental group covered with Bio-Gide when compared with control group, with and without Bio-Gide. The histomorphometrics showed no difference between groups regarding the non-vital mineralized tissue area. For vital mineralized tissue area, the experimental group covered with Bio-Gide obtained a higher percentage area when compared with control group, with and without Bio-Gide. For non-mineralized tissue area, the experimental group covered with Bio-Gide obtained a lower percentage area when compared with control group, with and without Bio-Gide. Conclusion. Both autologous bone marrow and membrane can contribute to the enhancement of bone healing.

Maxillary Sinus Augmentation Combining Bio-Oss with the Bone Marrow Aspirate Concentrate: A Histomorphometric Study in Humans.

Purpose. To investigate the regenerative results obtained with the association of bone marrow aspirate concentrate using the Bone Marrow Aspirate Concentrate (BMAC) method to a xenogeneic bone graft (Bio-Oss) in sinus floor elevation. Materials and Methods. Using a randomized controlled study design in eight consecutive patients (age of 55.4 ± 9.2 years), 16 sinus floor lift procedures were performed with Bio-Oss alone (control group, CG, n = 8) or combined with bone marrow aspirate concentrate obtained via the BMAC method (test group, TG, n = 8). Six months after the grafting procedures, bone biopsies were harvested during implant placement and were analyzed by histomorphometry. Results. Histomorphometric analysis revealed a significantly higher amount (p < 0.05) of vital mineralized tissue in TG when compared to the CG (55.15 ± 20.91% and 27.30 ± 5.55%, resp.). For nonvital mineralized tissue, TG presented a statistically higher level of Bio-Oss resorption (p < 0.05) when compared with the CG (6.32 ± 12.03% and 22.79 ± 9.60%, resp.). Both groups (TG and CG) showed no significantly different levels (p > 0.05) of nonmineralized tissue (38.53 ± 13.08% and 49.90 ± 7.64%, resp.). Conclusion. The use of bone marrow concentrate obtained by BMAC method increased bone formation in sinus lift procedures.

Autologous Periosteum-Derived Micrografts and PLGA/HA Enhance the Bone Formation in Sinus Lift Augmentation

Sinus lift augmentation is a procedure required for the placement of a dental implant, whose success can be limited by the quantity or quality of available bone. To this purpose, the first aim of the current study was to evaluate the ability of autologous periosteum-derived micrografts and Poly(lactic-co-glycolic acid) (PLGA) supplemented with hydroxyl apatite (HA) to induce bone augmentation in the sinus lift procedure. Secondly, we compared the micrografts behavior with respect to biomaterial alone, including Bio-Oss® and PLGA/HA, commercially named Alos. Sinus lift procedure was performed on 24 patients who required dental implants and who, according to the study design and procedure performed, were divided into three groups: group A (Alos + periosteum-derived micrografts); group B (Alos alone); and group C (Bio-Oss® alone). Briefly, in group A, a small piece of periosteum was collected from each patient and mechanically disaggregated by Rigenera® protocol using the Rigeneracons medical device. This protocol allowed for the obtainment of autologous micrografts, which in turn were used to soak the Alos scaffold. At 6 months after the sinus lift procedure and before the installation of dental implants, histological and radiographic evaluations in all three groups were performed. In group A, where sinus lift augmentation was performed using periosteum-derived micrografts and Alos, the bone regeneration was much faster than in the control groups where it was performed with Alos or Bio-Oss® alone (groups B and C, respectively). In addition, the radiographic evaluation in the patients of group A showed a radio-opacity after 4 months, while after 6 months, the prosthetic rehabilitation was improved and was maintained after 2 years post-surgery. In summary, we report on the efficacy of periosteum-derived micrografts and Alos to augment sinus lift in patients requiring dental implants. This efficacy is supported by an increased percentage of vital mineralized tisssue in the group treated with both periosteum-derived micrografts and Alos, with respect to the control group of Alos or Bio-Oss® alone, as confirmed by histological analysis and radiographic evaluations at 6 months from treatment.

Can bone marrow aspirate concentrate change the mineralization pattern of the anterior maxilla treated with xenografts? A preliminary study

Objective: To evaluate bony reconstruction of the atrophic anterior maxilla using particulate grafts with or without autologous bone marrow aspirate concentrate (BMAC). Materials and Methods: Eight patients with atrophy of the anterior maxilla due to teeth loss were selected and split into groups according to the type of material used: Control Group (CG) (n = 4) - particulate xenograft only and Test Group (TG) (n = 4) - a combination of particulate xenograft and BMAC. Both groups received a collagen membrane to cover the xenograft. After 4 months, during implant placement, a sample of bone was removed from the graft area using a 2 mm diameter trephine bur. The specimens were fixed and preserved for histomorphometric evaluation, which included the following parameters: Mineralized tissue (MT) and non-MT (NMT). Cone beam computed tomography was performed at 3 time intervals to measure bone thickness: (1) Before grafting, (2) 4 months and (3) 8 months postgrafting, using localized bone gain (mm) as the outcome variable. Results: Tomographic analysis revealed bone gain in CG of 3.78 ± 1.35 mm and 4.34 ± 1.58 mm at 4 and 8 months, respectively. TG showed an increase of 3.79 ± 0.52 mm and 4.09 ± 1.33 mm after 4 and 8 months, respectively. Histomorphometric analysis revealed that, for CG, MT- and NMT-related values were 52.3% ± 16.78% and 47.70% ± 5.55%, respectively, whereas for TG, they were 65.04% ± 20.98% and 34.96 ± 10.38, respectively. Conclusion: Although radiographic bone gain appeared similar between the groups, the use of BMAC obtained via the BMAC® method revealed an increased mineralization trend in the anterior maxilla. It must be highlighted, however, that this is a preliminary study with a relatively small sample population and further studies with larger sample sizes are needed to verify these results.

Use of Bone Allograft With or Without Bone Marrow Aspirate Concentrate in Appositional Reconstructions: A Tomographic and Histomorphometric Study

Objectives: To evaluate bone allograft associated to bone marrow aspirate concentrate (BMAC), in maxillary reconstructions. Materials and Methods: Ten patients with alveolar bone deficiency in the anterior maxilla were randomly divided into control group (CG) and test group (TG). A bone block allograft was placed in both groups, but the graft was impregnated with BMAC only in TG. Computed tomography was performed 7 days (T1) and 6 months (T2) after the grafting procedure, and volume and bone density measurements were carried out. Histomorphometric analysis was performed at T2. Results: Bone volume loss from T1 to T2 was significant only in TG. The bone density in the buccal region of the graft was significantly higher in TG than in CG. There was no significant difference between the groups, in respect to mineralized tissue (MT) and nonmineralized tissue (NMT), in that MT values were 37.77% ± 15.19% and 43.85% ± 10.94%, and NMT values were 62.15% ± 14.90% and 56.30% ± 10.72%, respectively, for CG and TG. The intragroup difference for the MT/NMT ratio was statistically significant in CG but not significant in TG. Conclusions: The use of BMAC resulted in an improved pattern of bone formation, with higher bone density in the peripheral regions of the graft.

Xenograft impregnated with bone marrow mononuclear fraction for appositional bone regeneration in rabbit calvaria: a clinical and histomorphometric study.

PURPOSE This study investigated the combination of a bone marrow mononuclear fraction with a bone xenograft material in an appositional bone regeneration technique. MATERIALS AND METHODS Twelve New Zealand rabbits were randomly divided into two groups of six animals each. Bone reconstruction situations were created using titanium cylinders; these were filled with xenograft in group 1 animals and xenograft enriched with bone marrow mononuclear fraction in group 2 animals. Two cylinders were adapted onto the calvaria of each animal. Bone marrow aspirate was obtained from the tibia of every animal. After 8 weeks, the animals were sacrificed and the parietal bone and cylinders were fixed in 10% formalin for analysis of clinical measurement of the bone volume formed inside the cylinders and histomorphometric evaluation of parameters such as vital mineralized tissue (VMT), nonvital mineralized tissue (NVMT), nonmineralized tissue (NMT), and vital mineralized tissue in contact with titanium (VMTCT). RESULTS Clinically, groups 1 and 2 demonstrated bone volume gains of 88.29% ± 25.97% and 98.96% ± 0.00%, respectively. Histomorphometry for groups 1 and 2, respectively, demonstrated the following mean values: VMT, 18.96% ± 8.99% and 28.02% ± 8.76%; NVMT, 28.43% ± 2.44% and 25.57% ± 2.33%; NMT, 52.61% ± 10.80% and 46.42% ± 10.06%; and VMTCT, 4.98% ± 4.30% and 27.29% ± 9.58%. CONCLUSION The results of this study suggest that the use of the bone marrow mononuclear fraction can improve bone healing and the level of osseointegration.

Use of Bone Marrow Aspirate Concentrate (BMAC) Associated with Hyperbaric Oxygenation Therapy in Maxillary Appositional Bone Reconstruction. A Randomized Clinical Trial

Objectives: The objective of this study was to evaluate bone reconstruction using xenograft alone and associated with bone marrow aspirate concentrate (BMAC) and hyperbaric oxygen therapy. Material and Methods: Twenty-four maxillary edentulous patients were randomly assigned into three groups: Control group (CG)—xenograft bone alone (n = 8); Group 1 (G1)—xenogeneic bone block combined with BMAC (n = 8), and Group 2 (G2)—xenogeneic bone block combined with BMAC and hyperbaric oxygenation (n = 8). Bone biopsies were harvested 6 months after grafting. Vital Mineralized Tissue (VMT), Non-vital Mineralized Tissue (NVMT), and Non-Mineralized Tissue (NMT) were measured. Computed tomography was also performed on three occasions T0 (preoperative), T4 (4 months postoperative), and T8 (8 months postoperative). The difference between T4 and T8 values with respect to T0 was used to determine the thickness level gain after 4 and 8 months, respectively. Results: The tomographic evaluation did not show significant differences between the groups either at 4 or at the 8 months postoperatively. Regarding the histomorphometric analysis, CG had the lowest percentages of VMT (36.58 ± 9.56%), whereas G1 and G2 had similar results (55.64 ± 2.83% and 55.30 ± 1.41%, respectively). Concerning NMT and NVMT levels, the opposite was observed, with CG levels of 51.21 ± 11.54% and 11.16 ± 2.37%, G1 of 39.76 ± 11.48% and 3.65 ± 0.87%, and G2 of 40.3 ± 11.48% and 4.10 ± 0.87%, respectively. Conclusions: The use of bone block xenograft associated with BMAC resulted in a significant increase of bone neoformation when compared to the xenograft alone, though hyperbaric oxygenation did not enhance the results.

Horizontal Bone Reconstruction on sites with different amounts of native bone: a retrospective study

The lack of guidelines for bone augmentation procedures might compromise decision making in implantology. The objective of this study was to perform a retrospective study to verify the outcomes of horizontal bone reconstruction in implant dentistry with different types of materials and amounts of native bone in the recipient bed to allow for a new guideline for horizontal bone reconstruction. One hundred preoperative CT scans were retrospectively evaluated and categorized in accordance to horizontal bone defects as presence (Group P) or absence (Group A) of cancellous bone in the recipient bed. Different approaches were used to treat the edentulous ridge and the outcomes were defined either as satisfactory or unsatisfactory regarding the possibility of implant placement. The percentage distribution of the patients according to the presence or absence of cancellous bone was 92% for Group P and 8% for Group A. In Group P, 98% of the patients had satisfactory outcomes, and the use of autografts had 100% of satisfactory outcomes in this group. In Group A, 37.5% of the patients had satisfactory outcomes, and the use of autografts also yielded 100% of satisfactory outcomes. The use of allografts and xenografts in Group A had 0% and 33.3% of satisfactory outcomes, respectively. Therefore, it seems reasonable to speculate that the presence of cancellous bone might be predictive and predictable when the decision includes bone substitutes. In cases of absence of cancellous bone in the recipient bed, the use of a vitalized graft seems to be mandatory.

Long-term retrospective study of implants placed after sinus floor augmentation with fresh-frozen homologous block

Aim: The aim of this study was to analyze and follow-up implants placed in the posterior maxillary regions previously grafted with homologous bone. Materials and Methods: Forty-one grafts with homologous bone blocks were performed in maxillary sinuses, and 121 implants were placed in premolar and molar regions approximately 6 months after the grafts. Patients were followed up for periods varying from 12 to 124 months after rehabilitation. Results: The results showed two implant failures, for a 98.3% success rate during the follow-up period. Discussion: The implants placed had an average torque of 40 N-cm, regardless of the, design, diameter, and length of the implants used. Conclusion: After following up on the implants placed in this study, we concluded that those placed in regions of the maxillary sinuses previously grafted with homologous bone blocks had high long-term success rates and met the functional masticatory requirements.