Anorganic Bovine Bone Mineral Research Articles

Antibody-Mediated Osseous Regeneration for Bone Tissue Engineering in Canine Segmental Defects

Among many applications of therapeutic monoclonal antibodies (mAbs), a unique approach for regenerative medicine has entailed antibody-mediated osseous regeneration (AMOR). In an effort to identify a clinically relevant model of craniofacial defect, the present study investigated the efficacy of mAb specific for bone morphogenetic protein- (BMP-) 2 to repair canine segmental mandibular continuity defect model. Accordingly, a 15 mm unilateral segmental defect was created in mandible and fixated with a titanium plate. Anorganic bovine bone mineral with 10% collagen (ABBM-C) was functionalized with 25 μg/mL of either chimeric anti-BMP-2 mAb or isotype-matched mAb (negative control). Recombinant human (rh) BMP-2 served as positive control. Morphometric analyses were performed on computed tomography (CT) and histologic images. Bone densities within healed defect sites at 12 weeks after surgery were 1360.81 ± 10.52 Hounsfield Unit (HU), 1044.27 ± 141.16 HU, and 839.45 ± 179.41 HU, in sites with implanted anti-BMP-2 mAb, rhBMP-2, and isotype mAb groups, respectively. Osteoid bone formation in anti-BMP-2 mAb (42.99% ± 8.67) and rhBMP-2 (48.97% ± 2.96) groups was not significantly different but was higher (p < 0.05) than in sites with isotype control mAb (26.8% ± 5.35). In view of the long-term objective of translational application of AMOR in humans, the results of the present study demonstrated the feasibility of AMOR in a large clinically relevant animal model.

Guided Bone Regeneration with Collagen Membranes and Particulate Graft Materials: A Systematic Review and Meta-Analysis.

The aim of this meta-analysis was to evaluate different methods for guided bone regeneration using collagen membranes and particulate grafting materials in implant dentistry. An electronic database search and hand search were performed for all relevant articles dealing with guided bone regeneration in implant dentistry published between 1980 and 2014. Only randomized clinical trials and prospective controlled studies were included. The primary outcomes of interest were survival rates, membrane exposure rates, bone gain/defect reduction, and vertical bone loss at follow-up. A meta-analysis was performed to determine the effects of presence of membrane cross-linking, timing of implant placement, membrane fixation, and decortication. Twenty studies met the inclusion criteria. Implant survival rates were similar between simultaneous and subsequent implant placement. The membrane exposure rate of cross-linked membranes was approximately 30% higher than that of non-cross-linked membranes. The use of anorganic bovine bone mineral led to sufficient newly regenerated bone and high implant survival rates. Membrane fixation was weakly associated with increased vertical bone gain, and decortication led to higher horizontal bone gain (defect depth). Guided bone regeneration with particulate graft materials and resorbable collagen membranes is an effective technique for lateral alveolar ridge augmentation. Because implant survival rates for simultaneous and subsequent implant placement were similar, simultaneous implant placement is recommended when possible. Additional techniques like membrane fixation and decortication may represent beneficial implications for the practice.

Alveolar ridge dimensional changes following ridge preservation procedure with novel devices: part 3 – histological analysis in non‐human primate model

This study sought to investigate the histological changes following tooth extraction, ridge preservation and augmentation, using novel devices designed to obturate the oral orifice of extraction sockets (SocketKAP™) and provide structural support for sockets with defective bony walls (SocketKAGE™) in a non-human primate model. Six Macaca fascicularis were imaged by cone beam computed tomography to register their preoperative alveolar bone. Three teeth were extracted in each animal, yielding intact socket walls and were divided into three intervention groups: unassisted healing negative control (Group A); SocketKAP™ (Group B); filled with anorganic bovine bone mineral (ABBM)+SocketKAP™ (Group C). Three additional teeth were extracted in each animal, followed by surgical resection of the entire buccal alveolar bone and divided into three groups: negative control (Group D); SocketKAP™+SocketKAGE™ (Group E); ABBM+SocketKAP™+SocketKAGE™ (Group F). Animals were euthanized after 12weeks, and treatment sites were examined by histology and histomorphometric analysis. Control sockets with unassisted healing (Groups A and D) underwent severe loss of bone width, height and total area (approximately 40-60% loss). Application of SocketKAP™ in sites with intact walls, as well as SocketKAP™ plus SocketKAGE™ in sites with defective buccal walls lead to higher preservation of alveolar bone height after 12weeks post-intervention. Addition of ABBM leads to the highest degree of alveolar bone dimensional preservation. Control sites with unassisted healing (Groups A and D), as well as sites treated with extraction socket devices (Groups B and E) without ABBM yielded higher percentage of vital bone, compared with sites filled with ABBM (Groups C and F). No adverse histological responses were noted to SocketKAP™ or SocketKAGE™ devices. SocketKAP™+SocketKAGE™ devices proved effective in reducing post-extraction alveolar bone resorption mediating favorable wound healing within sockets. Addition of ABBM was associated with reduced volumetric loss, although the bone fill was characterized by less mature as well as more woven bone.

Effects of platelet-rich fibrin on healing of intra-bony defects treated with anorganic bovine bone mineral.

Anorganic bovine bone mineral (ABBM) is extensively used in the treatment of intra-bony defects. Platelet-rich fibrin (PRF) is a new-generation platelet concentrate with a simplified technique. Although certain studies have reported the use of PRF in the treatment of intra-bony defects, to date, none of them have evaluated its additive effects with ABBM. Therefore, a randomised, split-mouth clinical trial was conducted to compare healing of intra-bony defects treated with an ABBM-PRF combination with healing of those treated with ABBM alone. By using a split-mouth design, 15 paired intra-bony defects were randomly treated with either ABBM alone (control group) or ABBM-PRF combination (test group). Following clinical parameters and radiographical measurements were recorded at baseline and 6 months after treatment: plaque index (PI), gingival index (GI), probing depth (PD), gingival recession (GR), clinical attachment level (CAL), vertical bone loss, depth of defect and defect angle. Preoperative clinical and radiographical measurements were similar for the test and control groups. Statistically significant reductions in GI, PD, CAL, vertical bone loss, depth of intra-bony defect and widening of defect angle were detected after treatment in both groups. With respect to inter-group analysis, gain in CAL was significantly greater in the test group than in the control group, whereas no inter-group differences were observed in any other parameter. The results of this study indicate that both therapies are effective in the treatment of intra-bony defects.

Alveolar ridge dimensional changes following ridge preservation procedure using SocketKAP(™) : exploratory study of serial cone-beam computed tomography and histologic analysis in canine model.

The aim of this pilot study was to examine the kinetics of alterations in alveolar ridge width and height following tooth extraction with and without ridge preservation, using anorganic bovine bone mineral (ABBM) and a novel device (SocketKAP(™) ) designed for obturation of socket orifice. Maxillary left and right PM1 and mandibular right PM2 and PM4 were extracted on six beagle dogs and treated as follows: Group A: negative control; Group B: SocketKAP(™) alone; Group C: ABBM+SocketKAP(™) . Serial cone-beam computed tomography (CBCT) was taken at 0-, 1-, 2-, 4-, 8- and 12-week intervals to calculate the rate of alveolar bone loss, followed by histologic and histomorphometric analyses at 12weeks. Across group outcomes were compared. Without additional intervention, the crestal-most 3mm of alveolar bone width lost approximately 0.21-0.28mm per week. The rate of alveolar buccal bone height loss was 0.19mm per week. Comparatively, in group C, the alveolar bone was relatively stable, with loss of only 0.003-0.13mm of width and 0.12mm of height per week. These differences were statistically significant. The alveolar bone in sites treated by SocketKAP(™) alone was significantly different from control only at select time points and locations of the ridge, presumably due to small sample size. Without additional intervention, tooth extraction was accompanied by rapid loss of alveolar ridge width and height. Applications of SocketKAP(™) and ABBM were effective in reducing alveolar crestal width and height loss following tooth extraction.

An open randomized controlled clinical trial to evaluate ridge preservation and repair using SocketKAP(™) and SocketKAGE(™) : part 1-three-dimensional volumetric soft tissue analysis of study casts.

The aims of this study were to evaluate (i) the efficacy of ridge preservation and repair involving SocketKAP(™) and SocketKAGE(™) devices following tooth removal; and (ii) ridge contour changes at 6months post-extraction in intact sockets and sockets with dehiscence defects. Thirty-six patients required a total of 61 teeth to be extracted. Five cohorts were established with groups A-C involving intact sockets and groups D and E involving facial dehiscence: (A) Negative Control; (B) SocketKAP(™) alone; (C) Anorganic Bovine Bone Mineral (ABBM)+SocketKAP(™) ; (D) Negative Control; and (E) ABBM+SocketKAP(™) +SocketKAGE(™) . Preoperative CBCT and laser-scanned casts were obtained. Teeth segmented from preoperative CBCT were merged with study cast images to allow for digital removal of teeth from the casts. Volumetric measurements of ridge contour were performed. Images of preoperative and 6months post-operative casts were superimposed to measure ridge contour changes. Post-extraction contour loss occurred in all sockets primarily in the crestal 3mm but was also detected up to 6mm from alveolar crest. For intact sockets, SocketKAP(™) or SocketKAP(™) +ABBM interventions led to greater percentages of remaining ridge contour when compared to controls. A significant difference favoring SocketKAP(™) +SocketKAGE(™) +ABBM treatment was observed for sockets with facial dehiscence when compared to controls. SocketKAP(™) , with or without ABBM, significantly limited post-extraction ridge contour loss in intact sockets. In the absence of a group treated with only the SocketKAGE(™) , it is not possible to determine its efficacy, although the combination of SocketKAGE(™) +SocketKAP(™) +ABBM was effective in limiting post-extraction ridge contour loss in sockets with dehiscence defects.

An open randomized controlled clinical trial to evaluate ridge preservation and repair using SocketKAP(™) and SocketKAGE(™) : part 2 - three-dimensional alveolar bone volumetric analysis of CBCT imaging.

The aims of this study were (i) to evaluate the efficacy of ridge preservation and repair procedures involving the application of SocketKAP(™) and SocketKAGE(™) devices following tooth removal and (ii) to evaluate alveolar bone volumetric changes at 6months post-extraction in intact sockets or those with facial wall dehiscence defects using 3-dimensional pre- and postoperative CBCT data. Thirty-six patients required 61 teeth extracted. Five cohorts were established: Group A: Intact Socket Negative Control Group B: Intact Socket + SocketKAP(™) Group C: Intact Socket Filled with Anorganic Bovine Bone Mineral (ABBM) + SocketKAP(™) Group D: Facial Dehiscence Socket Negative Control Group E: Facial Dehiscence Socket Filled with ABBM + SocketKAP(™) + SocketKAGE(™) . Preoperative CBCT scans were obtained followed by digital subtraction of the test teeth. At 6months post-extraction, another CBCT scan was obtained. The pre- and postoperative scans were then superimposed, allowing highly accurate quantitative determination of the 3D volumetric alveolar bone volume changes from baseline through 6months. Significant volumetric bone loss occurred in all sockets, localized mainly in the 0-3mm zone apical to the ridge crest. For intact sockets, SocketKAP(™) + ABBM treatment led to a statistically significant greater percentage of remaining mineralized tissue volume when compared to negative control group. A significant difference favoring SocketKAP(™) + SocketKAGE(™) + ABBM treatment was observed for sockets with facial dehiscence defects compared to the negative control group. SocketKAP(™) , with ABBM, appears effective in limiting post-extraction volumetric bone loss in intact sockets, while SocketKAP(™) + SocketKAGE + ABBM appears effective in limiting post-extraction bone loss in sockets with dehiscence defects.

Alveolar ridge dimensional changes following ridge preservation procedure: part-2 - CBCT 3D analysis in non-human primate model.

The aim of this study was to evaluate the efficacy of ridge preservation involving novel devices used for obturation of socket orifice (Socket cap; SocketKAP(™) ) and resorbable cage used for space maintenance in sites with facial wall dehiscence (Socket cage; SocketKAGE(™) ). Eight teeth were extracted in each of six Macaca fascicularis non-human primates. Six intervention groups consisted of the following: Group A: intact socket negative control. Group B: intact socket: socket cap. Group C: intact socket filled with anorganic bovine bone mineral (ABBM) + socket cap. Group D: dehiscence: negative control. Group E: dehiscence: socket cap + socket cage. Group F: dehiscence: filled with ABBM + socket cap + socket cage. CBCT scans were obtained preoperatively and at 6 and 12weeks following intervention. The pre- and postoperative scans were superimposed, to quantify 3D volumetric alveolar bone changes. Volumetric bone loss occurred in all sockets, not only within the cretal zone (0-3mm) to the ridge crest, as has been commonly reported by other investigators, but significant bone loss was also detected in the zone which was 3-6mm apical to the alveolar crest. For intact sockets, socket cap + ABBM led to significantly greater percentages of remaining bone volume when compared to groups A and B. A significant difference favoring socket cap + socket cage + ABBM treatment was observed for sockets with facial dehiscence defects compared to groups D and E. Socket cap in conjunction with ABBM appears effective in limiting post-extraction volumetric bone loss in intact sockets, while socket cap + socket cage + ABBM appears effective in limiting post-extraction bone loss in sockets with dehiscence defects.

Bone response to collagenized xenografts of porcine origin (mp3(®) ) and a bovine bone mineral grafting (4BONE(™) XBM) grafts in tibia defects: experimental study in rabbits.

This study aimed to carry out the evaluation of bone response of new bone formation to two different xenografts (bovine and porcine) biomaterials inserted in rabbit tibiae. The study used a total of 20 male New Zealand albino rabbits. They received a total of 40 grafts in the proximal metaphyseal areas of both tibiae. Two biomaterials were evaluated: 20 porcine xenografts, as a bone granulate (OsteoBiol(®) MP3(®) ; Tecnoss srl, Giaveno, Italy), were placed in the proximal metaphyseal area of the right tibia, 20 anorganic bovine bone mineral grafting (4BONE(™) XBM, MIS Implants Inc., BARLEV, Israel) were placed in the left tibia. Following graft insertion, the animals were sacrificed in two groups of 10 animals, after 1 and 4months, respectively. For each group, biomaterials were analyzed: newly formed bone, residual graft materials and the connective tissue. Histomorphometric, EDX analysis and element mapping were performed at 1 and 4months after graft insertion. At 4months after treatment, the bone defects displayed radiological images that showed complete repair of osseous defects. Histomorphometric evaluation showed that for the porcine xenograft, the study averages for newly formed bone represented 84.23±2.9%, while bovine matrix was 79.34±2.1%. For residual graft material, the porcine biomaterial had 11.23±1.7% and the bovine graft 31.56±2.3%. Finally, the connective tissue for MP3 was 10.33±1.8%, while for the 4BONE(™) XBM we obtained 14.34±2.9%. Element analysis revealed higher percentages of Ca (54±9%) and P (35±6%) in the group B than group A and control group (P<0.05). Defects of a critical size in a rabbit tibia model can be sealed using a bovine porous biphasic calcium phosphate and MP3 material; this supports new bone formation, creates a bridge between borders, and facilitates bone ingrowth in both biomaterials. Furthermore, this study observed partial dissolution of the mineral phase of four bone graft and complete resorption of porcine MP3 biomaterial and its incorporation into the surrounding bone. Depending on clinical needs, each biomaterial could be useful in daily clinical practice.

A histomorphometric assessment of collagen-stabilized anorganic bovine bone mineral in maxillary sinus augmentation - a prospective clinical trial.

To histomorphometrically compare the use of collagen-stabilized anorganic bovine bone (ABBM-C) (test) to anorganic bovine bone+autogenous bone (ABBM+AB) (control) in maxillary sinus augmentation. Forty (n=40 sinuses) patients underwent sinus augmentation and received either control (20 sinuses) or test bone graft (20 sinuses). Bone samples were harvested from the augmented sinuses 5months postgrafting. The samples were processed for histomorphometry, which assessed within the primary region of interest (ROI-1), the area fraction of new bone (%NB), graft particle osseointegration (% OI), residual graft (%RG), and soft tissue components (% STM). The same analysis was also carried out in a second region of interest (ROI-2) located in a zone 1mm proximal to the previous maxillary sinus floor. In both ROI-1 and ROI-2, the mean % NB, %RG, and %STM in the control group were similar to mean values in the test group. The % OI was significantly greater in the control group (42.0 +/- 26.8) when compared to the test group (19.6 +/- 27.3) in ROI-2 (P<0.05). No statistically significant differences were seen when ROI-1 and ROI-2 were compared except for improved %OI in ROI-2 in the control group. The mean proportion of lamellar bone to woven bone in the control group (1.22±1.48) was significantly greater than the test group (0.38±0.29) (P<0.05). ABBM-C exhibited very similar histomorphometric parameters to the composite graft of ABBM+AB. The ABBM+AB group was more mature as indicated by the significantly greater proportion of lamellar bone when compared to the ABBM-C. Improved % OI was seen in the zone proximal to the resident bony floor in the ABBM+AB group. Based on histological assessment, ABBM-C is a suitable bone substitute for the purposes of maxillary sinus augmentation. Its clinical utility may be indicated in cases of sinus membrane perforation and insufficient autogenous bone in the local area.

Biomechanical analysis of engineered bone with anti-BMP2 antibody immobilized on different scaffolds.

Recently we have demonstrated the ability of monoclonal antibodies (mAb) specific for bone morphogenetic protein (BMP)-2 immobilized on different scaffolds to mediate bone formation, a process referred to as Antibody Mediated Osseous Regeneration (AMOR). One of the key properties of regenerated bone is its biomechanical strength, in particular in load-bearing areas. This study sought to test the hypothesis that the biomechanical strength of regenerated bone depends of the mode of regeneration, as well as the scaffold used. Four different scaffolds, namely titanium granules (Ti), alginate hydrogel, anorganic bovine bone mineral (ABBM), and absorbable collagen sponge (ACS) were functionalized with anti-BMP-2 or isotype control mAb and implanted into rat critical-size calvarial defects. The morphology, density and strength of the regenerated bone were evaluated after 8 weeks. Results demonstrated that scaffolds functionalized with anti-BMP-2 mAb exhibited varying degrees of bone volume and density. Ti and ABBM achieved the highest bone volume, density, and strength of bone. When anti-BMP-2 mAb was immobilized on Ti or ABBM, the strength of the regenerated bone were 80% and 77% of native bone respectively, compared with 60% of native bone in sites implanted with rh-BMP-2. Control interventions with isotype mAb did not promote considerable bone regeneration and exhibited significantly lower mechanical properties. SEM analysis showed specimens immobilized with anti-BMP-2 mAb formed new bone with organized structure bridging the crack areas. Altogether, the present data demonstrated that the morphological and mechanical properties of bone bioengineered through AMOR could approximate that of native bone, when appropriate scaffolds are used. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1465-1473, 2016.

A histomorphometric assessment of collagen-stabilized anorganic bovine bone mineral in maxillary sinus augmentation - a randomized controlled trial in sheep.

To histomorphometrically compare the use of collagen-stabilized anorganic bovine bone (ABBM-C) (test) to anorganic bovine bone+autogenous bone (ABBM+AB) (control) in maxillary sinus augmentation. Nine sheep underwent bilateral sinus augmentation. Each sinus was randomized to receive either control or test bone graft. Three animals were sacrificed at 8weeks, and six animals were sacrificed at 16weeks post-grafting. The 18 sinuses were processed for histomorphometry, which assessed the area fraction of new bone (%NB), residual graft (%RG) and soft tissue components (% STM), as well as graft particle osseointegration (% OI), within three zones equally distributed from the augmented sinus floor. At week 16, a significant increase in %NB was evident across all three zones in the control group when compared to week 8. A significantly greater %NB was evident in the control group when compared to the test group in zones 2 (P<0.001) and 3 (P<0.001). There was a significant increase in %OI in week 16 when compared to week 8 across all three zones in the control group (P<0.001). %OI in the control group was significantly greater across all three zones when compared to the test group at week 16 (P<0.001). Zone was found to be a significant main effect (P<0.001) that was independent of time and treatment with decreasing %OI in distant zones. %RG did not significantly change with time for both groups. There was a significant reduction in %ST in week 16 when compared to week 8 across all three zones in the control group (P<0.001). %ST in the test group was significantly greater across all zones when compared to the control group at week 16 (P<0.001). Both groups exhibited very similar histomorphometric measurements in the zones proximal to the resident sinus wall. The % NB and % OI were greatest in the zones proximal to resident bony walls and gradually decreased as the distance from the proximal walls increased. There was greater % NB and % OI in the control group when compared to the test group in the distant zone.

Alveolar ridge dimensional changes following ridge preservation procedure with novel devices: Part 1--CBCT linear analysis in non-human primate model.

AimThis study sought to investigate dimensional changes to the alveolar bone following extraction and application of novel devices used for obturation of socket orifice (socket cap) and space maintenance in sockets with facial dehiscence (socket cage).Material and methodsSix Macaca fascicularis had six teeth each removed according to the following intervention groups (groups A–C intact alveolar bone; D–E facial dehiscence): negative control (A); socket obturated with cap (B); filled with anorganic bovine bone mineral (ABBM) + socket cap (C); dehiscence negative control (D); socket cap + socket cage (E); ABBM + socket cap + socket cage (F). Serial CBCT scans at preoperatively, 6 and 12 weeks following intervention were compared to quantify linear alveolar bone alterations.ResultsWithout therapeutic intervention, intact sockets exhibited significant reduction in width at the crestal 2 mm of the ridge crest within 6 weeks. Compared with the negative control sites which lost up to 52% of crestal bone width, sites treated with socket cap + ABBM lost at most 4% of bone width at the crestal 2 mm. Similar results were seen in the dehiscence groups, with the combination of socket cap + socket cage + ABBM maintaining the greatest socket width and height dimensions.ConclusionsResults from the current non‐human primate study suggest that the socket cap and socket cage devices, when used in conjunction with xenograft proved effective in minimizing post‐extraction socket width loss and height seen in both intact sockets and sockets with facial dehiscence defects.

A comparative study of bovine bone used alone and in combination with transforming growth factor-beta for the treatment of periodontal osseous defects in humans

Objectives: Transforming growth factor-betas (TGFβs) are multifunctional growth factors with a broad range of biological activities in various cell types in many different tissues. The purpose of this study was to evaluate the treatment of intrabony defects with anorganic bovine bone mineral matrix combined with TGFβ-1 with the use of anorganic bovine bone alone. Materials and Methods: Thirty-two sites from sixteen patients were selected using a split-mouth study design for each patient, determined randomly through a biased coin randomization. One site received a mucoperiosteal flap, and the osseous defect was filled with the combined therapy (Group 1). The other site treated was with anorganic bovine bone alone and served as a control (Group 2). All the treated sites were covered with a bioabsorbable collagen membrane. The clinical parameters and radiographic follow-up examinations were recorded after 3, 6, 9, and 12 months. Results: Clinically, there was a statistically significant gain in the clinical attachment level (+5.03 ΁ 0.14 mm) and a statistically significant reduction of pocket probing depth (−5.16 mm ΁ 0.13) for Group 1 sites compared to sites in Group 2 (P ≤ 0.01). In addition, there were significant differences in bone density and a significant decrease of marginal bone loss after the combined therapy compared with the use of anorganic bovine bone alone (P ≤ 0.01). Conclusion: The use of anorganic bovine bone mineral matrix combined with TGFβ-1 seemed to be effective in the treatment of intrabony defects. This showed an improvement in the clinical outcome of periodontal therapy superior to the use of anorganic bovine bone on its own.

Isolation and Assessment of Mesenchymal Stem Cells Derived From Bone Marrow: Histologic and Histomorphometric Study in a Canine Periodontal Defect

The aim of the present study was to investigate an isolation procedure to culture mesenchymal stem cells derived from bone marrow and evaluate their potential in periodontal regeneration. Potential stem cells from bone marrow, aspirated from the iliac crest of nine mongrel canines 1 to 2 years of age, were cultivated. After the examination of surface epitopes of the isolated cells, the total RNA from osteogenic, adipogenic, and chondrogenic cell cultures were analyzed by reverse transcription polymerase chain reaction (RT-PCR) to confirm stem cell gene expressions. 2 × 10(7) mL of the stem cells were loaded on 0.2 mL of anorganic bovine bone mineral (ABBM) granules. In each animal, bilateral acute/chronic intrabony periodontal defects were created surgically and by placement of ligatures around the cervical aspect of the teeth. At week 5, after flap debridement, the bilateral defects were randomly assigned to 2 treatment groups: the control group received ABBM, and the test group received BMSCs-loaded ABBM. Eight weeks after transplantation, regenerative parameters were analyzed histologically and histometrically. The RNA expressions confirmed the cultivation of mesenchymal stem cell. More new cementum and periodontal ligament (PDL) were measured in the test group (cementum: 3.33 ± 0.94 vs 2.03 ± 1.30, P = 0.027; PDL: 2.69 ± 0.73 vs 1.53 ± 1.21, P = 0.026). New bone formation was similar in both groups (2.70 ± 0.86 vs 1.99 ± 1.31; P = 0.193). Mesenchymal stem cells derived from bone marrow should be considered a promising technique for use in patients with periodontal attachment loss and merits further investigations.

A Randomized, Blinded, Controlled Clinical Study of Particulate Anorganic Bovine Bone Mineral and Calcium Phosphosilicate Putty Bone Substitutes for Socket Preservation

The purpose of this study was to compare the clinical efficacy of an anorganic bovine bone graft particulate to that of a calcium phosphosilicate putty alloplast for socket preservation. Thirty teeth were extracted from 24 patients. The sockets were debrided and received anorganic bovine bone mineral (BOV, n=12), calcium phosphosilicate putty (PUT, n=12), or no graft (CTRL, n=6). The sockets were assessed clinically and radiographically 5 months later. Eight sockets in the BOV group and nine in the PUT group received implants 5 to 6 months postgrafting. The maximum implant insertion torque (MIT) was measured as an index of primary implant stability. The data were analyzed with the Mann-Whitney test. Both test groups had statistically significantly less reduction in mean ridge width (BOV: 1.39±0.57 mm; PUT: 1.26±0.41 mm) in comparison to the control group (2.53±0.59 mm). No statistically significant difference was identified between the test groups. MIT for PUT was ≤35 N/cm² (MIT grade 4) for seven of the nine implants. MIT values in the BOV group ranged from grade 1 (10 to 19 N/cm²) to grade 4, which was statistically significantly lower than for the PUT group. The overall implant success rate was 94.1% (16 of 17 implants were successful). No implants were lost in the PUT group; one implant failed in the BOV group. Both tested bone substitutes can be recommended for preservation of alveolar ridge width following extraction. PUT might be more suitable for achieving primary stability for implants placed at 5 to 6 months postextraction.

Healing patterns of critical size bony defects in rats after grafting with bone substitutes soaked in recombinant human bone morphogenetic protein-2: histological and histometric evaluation

The aim of the study was to evaluate the effect of different bone substitutes soaked in recombinant human bone morphogenetic protein-2 (rhBMP-2) on the healing of critical size defects in calvarial bone. Defects were created in 24 Sprague Dawley rats. The rhBMP-2 was diluted to obtain a final concentration of 0.2mg/ml. Rats were divided into four groups and treated as follows: in the first group the defect was filled with anorganic bovine bone mineral (ABBM) and rhBMP-2, the second group was treated with freeze-dried bone allograft (FDBA) and rhBMP-2, and the third group was treated with autogenous bone (AUTO). In the control group the defects were left untreated. Animals were killed after 8weeks and calcified histological sections prepared. Histometric measurements showed that mean (SD) bone formation was 4.00 (1.69)mm2 in the ABBM group, 2.56 (1.06)mm2 in the FDBA group, and 2.30 (0.34)mm2 in the AUTO group. The difference between the ABBM group and the other 3 groups was significant (p<0.0001) with a mean bone formation of 0.82 (0.25)mm2 in the control group. There was no significant difference between the FDBA and the AUTO groups (p=0.96). Within the limits of this study we concluded that the addition of rhBMP-2 to bone substitutes was efficacious in regenerating bone in critical size bone defects in calveria in rats.

Histomorphometric analysis of sinus augmentation using bovine bone mineral with two different resorbable membranes

The purpose of this study was to compare the effects of two different resorbable collagen membranes on new bone formation after sinus grafts with anorganic bovine bone mineral (BBM). For 64 patients presenting with an initial residual bone height ≤4 mm at the posterior maxilla, the sinus floors were grafted with BBM (Bio-Oss). The lateral windows were covered by one of the two bio-resorbable membranes, Bio-Arm or Bio-Gide. The histomorphometric data were obtained 7-15 months after sinus augmentation at the time of the implant installation. The core biopsy specimens of Bio-Arm (n = 37 sites) and Bio-Gide group (n = 22 sites) were compared. The results showed that the BBM particles were in direct contact with the newly formed bone in all cases. In histomorphometric analysis, the Bio-Gide group showed significantly higher new bone formation (33.3 ± 12%) compared with the Bio-Arm group (26.3 ± 8.1%) (P < 0.05). All the implants survived successfully after a mean follow-up of 35.3 months (range 22-63 months) in the Bio-Arm group and 55.5 months (range 35-66 months) in the Bio-Gide group. The amount of new bone in the specimens did not significantly correlate with the residual bone height at the time of surgery or the length of the healing period. The type of resorbable membrane did not readily affect the long-term survival of the implants at the grafted sinus. On the other hand, Bio-Gide group showed more new bone formation than the Bio-Arm group, which implied that the function of the membrane can influence the remodeling of the grafted sinus. As the amount of residual bone substitute particle had not decreased significantly over time, the results suggest that the BBM was rarely resorbable for at least 15 months after the surgery.

Growth Factor‐Mediated Sinus Augmentation Grafting With Recombinant Human Platelet‐Derived Growth Factor‐BB (rhPDGF‐BB): Two Case Reports

Introduction: In the following two case reports, growth factor‐mediated sinus augmentation surgery is used to treat significant posterior maxillary alveolar bone deficiency. At initial examination, preexisting subsinus alveolar bone height was ≤3 mm. A composite graft of anorganic bovine bone mineral (ABBM) + mineralized bone allograft was combined with recombinant human platelet‐derived growth factor‐BB (rhPDGF‐BB) for augmentation grafting via a traditional maxillary lateral wall osteotomy approach to the sinus. In both cases, early implant placement and loading following sinus grafting, as well as long‐term clinical follow‐up, document potential benefits of growth factor‐mediated bone regenerative sinus augmentation procedures. The significantly abbreviated durations seen in these two cases between sinus augmentation grafting and implant placement and prosthetic restoration, to the best of our knowledge, have not been previously reported in the literature.Case Presentations: Two adult males presented with severe posterior maxillary alveolar bone atrophy, with a maximum subsinus bone height of 3 mm in patient #1 and &lt;1 mm in patient #2. For each patient, a 50:50 particulate composite graft of ABBM and mineralized allograft was hydrated with 1 mL of 0.3 mg/mL rhPDGF‐BB. Four and one‐half (4.5) and 3.5 months following grafting in patient #1 and #2, respectively, implants were placed and core biopsy specimens obtained. Histologic examination of osteotomy cores demonstrated significant amounts of vital bone for each patient. Definitive implant‐supported restorations in full occlusion were placed 8.5 and 7.5 months following sinus grafting for patient #1 and #2, respectively. Three (3) and 2.4 years following implant placement, all implants were well integrated, with no evidence of radiolucency at the implant‐to‐bone interface.Conclusion: The addition of tissue‐engineered proteins, i.e., rhPDGF‐BB, to sinus augmentation protocols may allow earlier implant placement secondary to accelerated bone formation following grafting in the severely pneumatized sinus and may provide for increased long‐term positive clinical outcomes.

The Use of Platelet Rich Plasma, Bone Morphogenetic Protein-2 and Different Scaffolds in Oral and Maxillofacial Surgery - Literature Review in Comparison with Own Clinical Experience

ABSTRACTObjectivesThe purpose of this article was to review and critically assess the use of platelet rich plasma, recombinant human bone morphogenetic protein-2 and different scaffolds (i.e. tricalciumphosphate, polycaprolactone, demineralized bone matrix and anorganic bovine bone mineral) in oral and maxillofacial surgery comparing the relevant literature and own clinical experience.Material and MethodsA literature review was conducted using MEDLINE, MEDPILOT and COCHRANE DATABASE OF SYSTEMATIC REVIEWS. It concentrated on manuscripts and overviews published in the last five years (2006-2010). The key terms employed were platelet rich plasma, bone morphogenetic proteins and their combinations with the above mentioned scaffolds. The results of clinical studies and animal trials were especially emphasized. The statements from the literature were compared with authors’ own clinical data.ResultsNew publications and overviews demonstrate the advantages of platelet rich plasma in bone regeneration. The results from the literature review were discussed and compared with the publications detailing authors' own experiences.ConclusionsA favourable outcome concerning newly grown bone was achieved combining platelet rich plasma in addition to optimal matrices with or without recombinant human bone morphogenetic protein-2, depending on the clinical case. As a consequence, the paradigm shift from transplantation of autogenous bone to bone tissue engineering appears promising.