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Resident Bone (resident + bone)
Selected AbstractsAlveolar ridge augmentation using implants coated with recombinant human growth/differentiation factor-5: histologic observationsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 8 2010Giuseppe Polimeni Polimeni G, Wikesjö UME, Susin C, Qahash M, Shanaman RH, Prasad HS, Rohrer MD, Hall J. Alveolar ridge augmentation using implants coated with recombinant human growth/differentiation factor-5: histologic observations. J Clin Periodontol 2010; 37: 759-768 doi: 10.1111/j.1600-051X.2010.01579.x. Abstract Objectives: In vitro and in vivo preclinical studies suggest that growth/differentiation factor-5 (GDF-5) may induce local bone formation. The objective of this study was to evaluate the potential of recombinant human GDF-5 (rhGDF-5) coated onto an oral implant with a purpose-designed titanium porous oxide surface to stimulate local bone formation including osseointegration and vertical augmentation of the alveolar ridge. Materials and Methods: Bilateral, critical-size, 5 mm, supraalveolar peri-implant defects were created in 12 young adult Hound Labrador mongrel dogs. Six animals received implants coated with 30 or 60 ,g rhGDF-5, and six animals received implants coated with 120 ,g rhGDF-5 or left uncoated (control). Treatments were alternated between jaw quadrants. The mucoperiosteal flaps were advanced, adapted, and sutured to submerge the implants for primary intention healing. The animals received fluorescent bone markers at weeks 3, 4, 7, and 8 post-surgery when they were euthanized for histologic evaluation. Results: The clinical examination showed no noteworthy differences between implants coated with rhGDF-5. The cover screw and implant body were visible/palpable through the alveolar mucosa for both rhGDF-5-coated and control implants. There was a small increase in induced bone height for implants coated with rhGDF-5 compared with the control, induced bone height averaging (±SD) 1.6±0.6 mm for implants coated with 120 ,g rhGDF-5 versus 1.2±0.5, 1.2±0.6, and 0.6±0.2 mm for implants coated with 60 ,g rhGDF-5, 30 ,g rhGDF-5, or left uncoated, respectively (p<0.05). Bone formation was predominant at the lingual aspect of the implants. Narrow yellow and orange fluorescent markers throughout the newly formed bone indicate relatively slow new bone formation within 3,4 weeks. Implants coated with rhGDF-5 displayed limited peri-implant bone remodelling in the resident bone; the 120 ,g dose exhibiting more advanced remodelling than the 60 and 30 ,g doses. All treatment groups exhibited clinically relevant osseointegration. Conclusions: rhGDF-5-coated oral implants display a dose-dependent osteoinductive and/or osteoconductive effect, bone formation apparently benefiting from local factors. Application of rhGDF-5 appears to be safe as it is associated with limited, if any, adverse effects. [source] Alveolar ridge augmentation using implants coated with recombinant human bone morphogenetic protein-7 (rhBMP-7/rhOP-1): histological observationsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 6 2010Cristiano Susin Susin C, Qahash M, Polimeni G, Lu PH, Prasad HS, Rohrer MD, Hall J, Wikesjö UME. Alveolar ridge augmentation using implants coated with recombinant human bone morphogenetic protein-7 (rhBMP-7/rhOP-1): histological observations. J Clin Periodontol 2010; 37: 574,581. doi: 10.1111/j.1600-051X.2010.01554.x. Abstract Background: Pre-clinical studies have shown that recombinant human bone morphogenetic protein-2 (rhBMP-2) coated onto purpose-designed titanium porous-oxide surface implants induces clinically relevant bone formation and osseointegration. The objective of this study was to examine the potential of rhBMP-7, also known as recombinant human osteogenic protein-1 (rhOP-1), coated onto titanium porous-oxide surface implants to support vertical alveolar ridge augmentation and implant osseointegration. Materials and Methods: Bilateral, critical-size, 5 mm, supraalveolar peri-implant defects were created in six young adult Hound Labrador mongrel dogs. The animals received implants coated with rhBMP-7 at 1.5 or 3.0 mg/ml randomized to contra-lateral jaw quadrants. The mucoperiosteal flaps were advanced, adapted, and sutured to submerge the implants for primary intention healing. The animals received fluorescent bone markers at 3, 4, 7, and 8 weeks post-surgery when they were euthanized for histological evaluation. Results: Without striking differences between treatments, the implant sites exhibited a swelling that gradually regressed to become hard to palpation disguising the implant contours. The histological evaluation showed robust bone formation; the newly formed bone assuming characteristics of the contiguous resident bone, bone formation (height and area) averaging 4.1±1.0 versus 3.6±1.7 mm and 3.6±1.9 versus 3.1±1.8 mm2; and bone density 56%versus 50% for implants coated with rhBMP-7 at 1.5 and 3.0 mg/ml, respectively. Both treatments exhibited clinically relevant osseointegration, the corresponding bone,implant contact values averaging 51% and 47%. Notable peri-implant resident bone remodelling was observed for implants coated with rhBMP-7 at 3.0 mg/ml. Conclusions: rhBMP-7 coated onto titanium porous-oxide surface implants induces clinically relevant local bone formation including osseointegration and vertical augmentation of the alveolar ridge, the higher concentration/dose associated with some local side effects. [source] Bone formation at recombinant human bone morphogenetic protein-2-coated titanium implants in the posterior maxilla (Type IV bone) in non-human primatesJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 11 2008Ulf M. E. Wikesjö Abstract Background: Studies using ectopic rodent and orthotopic canine models (Type II bone) have shown that titanium porous oxide (TPO) surface implants adsorbed with recombinant human bone morphogenetic protein-2 (rhBMP-2) induce local bone formation including osseointegration. The objective of this study was to evaluate local bone formation and osseointegration at such implants placed into Type IV bone. Material and Methods: rhBMP-2-coated implants were installed into the edentulated posterior maxilla in eight young adult Cynomolgus monkeys: four animals each received three TPO implants adsorbed with rhBMP-2 (2.0 mg/ml) and four animals each received three TPO implants adsorbed with rhBMP-2 (0.2 mg/ml). Contra-lateral jaw quadrants received three TPO implants without rhBMP-2 (control). Treatments were alternated between left and right jaw quadrants. Mucosal flaps were advanced and sutured to submerge the implants. The animals received fluorescent bone markers at weeks 2, 3, 4, and at week 16 when they were euthanized for histologic analysis. Results: Clinical healing was uneventful. Extensive local bone formation was observed in animals receiving implants adsorbed with rhBMP-2 (2.0 mg/ml). The newly formed bone exhibited a specific pinpoint bone,implant contact pattern regardless of rhBMP-2 concentration resulting in significant osseointegration; rhBMP-2 (2.0 mg/ml): 43% and rhBMP-2 (0.2 mg/ml): 37%. Control implants exhibited a thin layer of bone covering a relatively larger portion of the implant threads. Thus, TPO control implants bone exhibited significantly greater bone,implant contact (,75%; p<0.05). There were no statistically significant differences between rhBMP-2-coated and control implants relative to any other parameter including peri-implant and intra-thread bone density. Conclusion: rhBMP-2-coated TPO implants enhanced/accelerated local bone formation in Type IV bone in a dose-dependent fashion in non-human primates resulting in significant osseointegration. rhBMP-2-induced de novo bone formation did not reach the level of osseointegration observed in native resident bone within the 16-week interval. [source] Alveolar ridge augmentation using implants coated with recombinant human bone morphogenetic protein-7 (rhBMP-7/rhOP-1): radiographic observationsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 10 2008Knut N. Leknes Abstract Aim: The objective of this study was to radiographically evaluate the potential of a purpose-designed titanium porous-oxide implant surface coated with recombinant human bone morphogenetic protein-7 (rhBMP-7), also known as recombinant human osteogenic protein-1 (rhOP-1), to stimulate alveolar ridge augmentation. Material and Methods: Six young-adult Hound Labrador mongrel dogs were used. Three 10 mm titanium oral implants per jaw quadrant were placed 5 mm into the alveolar ridge in the posterior mandible following surgical extraction of the pre-molar teeth and reduction of the alveolar ridge leaving 5 mm of the implants in a supra-alveolar position. The implants had been coated with rhBMP-7 at 1.5 or 3.0 mg/ml and were randomized to contralateral jaw quadrants using a split-mouth design. The mucoperiosteal flaps were advanced, adapted, and sutured to submerge the implants. Radiographic registrations were made immediately post-surgery (baseline), and at weeks 4 and 8 (end of study). Results: rhBMP-7-coated implants exhibited robust radiographic bone formation. At 8 weeks, bone formation averaged 4.4 and 4.2 mm for implants coated with rhBMP-7 at 1.5 and 3.0 mg/ml, respectively. There were no significant differences between the rhBMP-7 concentrations at any observation interval. A majority of the implant sites showed voids within the newly formed bone at week 4 that generally resolved by week 8. The newly formed bone assumed characteristics of the resident bone. Conclusions: The titanium porous-oxide implant surface serves as an effective carrier for rhBMP-7 showing a clinically significant potential to stimulate local bone formation. [source] The critical-size supraalveolar peri-implant defect model: characteristics and useJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 11 2006Ulf M. E. Wikesjö Abstract Objective: Novel implant technologies and reconstructive therapies for alveolar augmentation require pre-clinical evaluation to estimate their biologic potential, efficacy, and safety before clinical application. The objective of this report is to present characteristics and use of the critical-size, supraalveolar, peri-implant defect model. Methods: Bilateral extraction of the mandibular premolars was performed in 12 Hound Labrador mongrel dogs following horizontal surgical cut-down of the alveolar ridge approximating 6 mm. Each jaw quadrant received three custom-produced TiUniteÔ, ,4.0 × 10 mm threaded implants placed into osteotomies prepared into the extraction sites of the third and fourth premolars. The implants exhibited a reference notch 5 mm from the implant platform to facilitate surgical placement leaving 5 mm of the implant in a supraalveolar position, and to serve as a reference point in the radiographic, histologic and histometric analysis. The implants were submerged under the mucoperiosteal flaps for primary intention healing. Fluorescent bone markers were administered at weeks 3 and 4 post-surgery, and pre-euthanasia. The animals were euthanized following an 8-week healing interval when block biopsies were collected for analysis. Results: Healing was generally uneventful. The radiographic and histometric evaluations demonstrate the limited osteogenic potential of this defect model. Whereas lingual peri-implant sites exhibited a mean (±SE) bone gain of 0.4±0.1 mm, resorption of the buccal crestal plate resulted in a mean bone loss of 0.4±0.2 mm for an overall osteogenic potential following sham-surgery averaging 0.0±0.1 mm. Overall bone density and bone,implant contact in the contiguous resident bone averaged 79.1±1.1% and 76.9±2.3%, respectively. Conclusion: The results suggest that the critical-size, supraalveolar, peri-implant defect model appears a rigorous tool in the evaluation of candidate technologies for alveolar reconstruction and osseointegration of endosseous oral implants. Limited innate osteogenic potential allows critical evaluation of osteogenic, osteoconductive, or osteoinductive technologies in a challenging clinical setting. [source] rhBMP-2/,BSM® Induces Significant Vertical Alveolar Ridge Augmentation and Dental Implant OsseointegrationCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 4 2002Ulf M.E. Wikesjö DDS ABSTRACT Background: Recombinant human bone morphogenetic protein 2 (rhBMP-2) in a carrier has been shown to induce significant bone formation. Several candidate carriers, however, lack structural integrity to offset compressive forces that may compromise rhBMP-2 bone induction, in particular, for challenging onlay indications such as alveolar ridge augmentation. Purpose: The objective of this study was to evaluate rhBMP-2 in a calcium-phosphate cement carrier, ,BSM, for vertical alveolar ridge augmentation and immediate dental implant Osseointegration. Materials and Methods: Six adult Hound Labrador mongrels with 5 mm critical size supra-alveolar peri-implant defects were used. Three animals received rhBMP-2/,BSM (rhBMP-2 at 0.40 and 0.75 mg/mL) in contralateral jaw quadrants (total implant volume/defect , 1.5 mL). Three animals received ,BSM without rhBMP-2 (control group). The animals were euthanized at 16 weeks post surgery, and block biopsies were processed for histologie and histometric analysis. Results: rhBMP-2/,BSM induced substantial augmentation of the alveolar ridge. Control sites exhibited limited new bone formation. Vertical bone augmentation averaged (SD) 4.9 ± 1.0 mm (rhBMP-2 at 0.40 mg/mL), 5.3 ± 0.3 mm (rhBMP-2 at 0.75 mg/mL), and 0.4 ± 0.4 mm (control); new bone area 8.5 ± 4.2 mm 2, 9.0 ± 1.9 mm 2, and 0.5 ± 0.4 mm 2; new bone density 55.1 ± 6.4%, 61.1 ± 6.0%, and 67.7 ± 9.5%; and new bone-implant contact 26.9 ± 17.5%, 28.5 ± 1.4%, and 24.6 ± 16.1%, respectively. Residual ,BSM comprised 1% of the new bone. Bone density for the contiguous resident bone ranged from 65 to 71%, and bone-implant contact ranged from 49 to 64%. Conclusions: Surgical implantation of rhBMP-2/,BSM appears an effective protocol for vertical alveolar ridge augmentation procedures and immediate dental implant Osseointegration and for onlay indications of lesser complexity. [source] | ||||||||||