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Bone Thickness (bone + thickness)
Kinds of Bone Thickness Selected AbstractsOsteoblast-Specific Targeting of Soluble Colony-Stimulating Factor-1 Increases Cortical Bone Thickness in Mice,,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 8 2003SL Abboud Abstract The soluble and membrane-bound forms of CSF-1 are synthesized by osteoblasts and stromal cells in the bone microenvironment. Transgenic mice, generated to selectively express sCSF-1 in bone, showed increased cortical thickness in the femoral diaphysis caused by new bone formation along the endosteal surface. The ability of sCSF-1 to enhance bone cell activity in vivo is potentially relevant for increasing cortical bone in a variety of disorders. Introduction: The soluble form of colony-stimulating factor-1 (sCSF-1) and the membrane-bound form of CSF-1 (mCSF-1) have been shown to support osteoclastogenesis in vitro; however, the effect of each peptide on bone remodeling in vivo is unclear. To determine the effect of sCSF-1, selectively expressed in bone, the skeletal phenotype of transgenic mice harboring the human sCSF-1 cDNA under the control of the osteocalcin promoter was assessed. Methods: At 5 and 14 weeks, mice were analyzed for CSF-1 protein levels, weighed, and X-rayed, and femurs were removed for peripheral quantitative computed tomography, histology, and histomorphometry. Results: High levels of human sCSF-1 were detected in bone extracts and, to a lesser extent, in plasma. Adult transgenic mice showed normal body weight and increased circulating monocytic cells. At 5 weeks, the femoral diaphysis was similar in CSF-1T and wt/wt littermates. However, by 14 weeks, the femoral diaphysis in CSF-1T mice showed increased cortical thickness and bone mineral density. In contrast to the diaphysis, the femoral metaphysis of CSF-1T mice showed normal cancellous bone comparable with wt/wt littermates at each time point. Histological sections demonstrated increased woven bone along the endosteal surface of the diaphysis and intracortical remodeling. Fluorochrome-labeling analysis confirmed endocortical bone formation in CSF-1T, with a 3.1-fold increase in the percentage of double-labeled surfaces and a 3.6-fold increase in the bone formation rate compared with wt/wt mice. Although remodeling resulted in a slightly porous cortex, sCSF-1 preferentially stimulated endocortical bone formation, leading to increased cortical thickness. Conclusions: These findings indicate that sCSF-1 is a key determinant of bone cell activity in the corticoendosteal envelope. [source] Murine TNF,ARE Crohn's disease model displays diminished expression of intestinal Ca2+ transportersINFLAMMATORY BOWEL DISEASES, Issue 6 2008Sylvie Huybers MSc Abstract Background: Patients suffering from Crohn's disease (CD) show increased incidence of low bone mineral density. Investigating this complication is difficult because the exact etiology of CD remains elusive. Mice carrying a deletion in the tumor necrosis factor (TNF) AU-rich elements (ARE) are reported as a model for human CD and are characterized by elevated TNF-, levels and inflammations in the terminal ileum. To evaluate whether these mice have a Ca2+ handling problem, this study analyzed the Ca2+ homeostasis in heterozygous TNF,ARE mice (TNF,ARE/+) in comparison to wildtype littermates. Methods: Beside serum Ca2+ and vitamin D levels, the expression of Ca2+ transporters was analyzed in intestine, kidney and bone using quantitative real-time PCR, Western blot and immunohistochemistry. Bone scans were performed to measure bone parameters. Results: Ca2+ transporters in duodenum (TRPV6, calbindin-D9K, PMCA1b) and kidney (TRPV5, calbindin-D28K, NCX1) showed significantly reduced mRNA expression levels in TNP,ARE/+ mice, except for renal TRPV5. In bone, only calbindin-D9K mRNA displayed a significant down-regulation. These findings were supported by declined duodenal calbindin-D9K and renal calbindin-D28K protein values. Likely, this down-regulation of Ca2+ transporters in TNP,ARE/+ mice is mediated by the 58 ± 9% reduction in serum 1,25(OH)2D3 levels. Diminished expression of Ca2+ transporters combined with unchanged serum Ca2+ levels assumes Ca2+ loss from bone to compensate for the body's overall Ca2+ shortage. Indeed, microcomputed tomography scanning demonstrated reduced trabecular and corticol bone thickness and volume in TNF,ARE/+ mice. This finding is further supported by increased total deoxypyridinoline in serum. Conclusions: Our results imply that TNF,ARE/+ mice have a disturbed Ca2+ homeostasis characterized by reduced duodenal and renal Ca2+ transporters, diminished 1,25(OH)2D3 levels, and increased bone resorption associated with profound bone abnormalities. (Inflamm Bowel Dis 2008) [source] Sustained BMP Signaling in Osteoblasts Stimulates Bone Formation by Promoting Angiogenesis and Osteoblast Differentiation,,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 7 2009Fengjie Zhang Abstract Angiogenesis and bone formation are tightly coupled during the formation of the skeleton. Bone morphogenetic protein (BMP) signaling is required for both bone development and angiogenesis. We recently identified endosome-associated FYVE-domain protein (endofin) as a Smad anchor for BMP receptor activation. Endofin contains a protein-phosphatase pp1c binding domain, which negatively modulates BMP signals through dephosphorylation of the BMP type I receptor. A single point mutation of endofin (F872A) disrupts interaction between the catalytic subunit pp1c and sensitizes BMP signaling in vitro. To study the functional impact of this mutation in vivo, we targeted expression of an endofin (F872A) transgene to osteoblasts. Mice expressing this mutant transgene had increased levels of phosphorylated Smad1 in osteoblasts and showed increased bone formation. Trabecular bone volume was significantly increased in the transgenic mice compared with the wildtype littermates with corresponding increases in trabecular bone thickness and number. Interestingly, the transgenic mice also had a pronounced increase in the density of the bone vasculature measured using contrast-enhanced ,CT imaging of Microfil-perfused bones. The vessel surface and volume were both increased in association with elevated levels of vascular endothelial growth factor (VEGF) in osteoblasts. Endothelial sprouting from the endofin (F872A) mutant embryonic metatarsals cultured ex vivo was increased compared with controls and was abolished by an addition of a VEGF neutralizing antibody. In conclusion, osteoblast targeted expression of a mutant endofin protein lacking the pp1c binding activity results in sustained signaling of the BMP type I receptor, which increases bone formation and skeletal angiogenesis. [source] Recombinant Human Parathyroid Hormone (1,34) [Teriparatide] Improves Both Cortical and Cancellous Bone StructureJOURNAL OF BONE AND MINERAL RESEARCH, Issue 11 2003Yebin Jiang MD Abstract Histomorphometry and ,CT of 51 paired iliac crest biopsy specimens from women treated with teriparatide revealed significant increases in cancellous bone volume, cancellous bone connectivity density, cancellous bone plate-like structure, and cortical thickness, and a reduction in marrow star volume. Introduction: We studied the ability of teriparatide (rDNA origin) injection [rhPTH(1,34), TPTD] to improve both cancellous and cortical bone in a subset of women enrolled in the Fracture Prevention Trial of postmenopausal women with osteoporosis after a mean treatment time of 19 months. This is the first report of a biopsy study after treatment with teriparatide having a sufficient number of paired biopsy samples to provide quantitative structural data. Methods: Fifty-one paired iliac crest bone biopsy specimens (placebo [n = 19], 20 ,g teriparatide [n = 18], and 40 ,g teriparatide [n = 14]) were analyzed using both two-dimensional (2D) histomorphometry and three-dimensional (3D) microcomputed tomography (,CT). Data for both teriparatide treatment groups were pooled for analysis. Results and Conclusions: By 2D histomorphometric analyses, teriparatide significantly increased cancellous bone volume (median percent change: teriparatide, 14%; placebo, ,24%; p = 0.001) and reduced marrow star volume (teriparatide, ,16%; placebo, 112%; p = 0.004). Teriparatide administration was not associated with osteomalacia or woven bone, and there were no significant changes in mineral appositional rate or wall thickness. By 3D cancellous and cortical bone structural analyses, teriparatide significantly decreased the cancellous structure model index (teriparatide, ,12%; placebo, 7%; p = 0.025), increased cancellous connectivity density (teriparatide, 19%; placebo, ,14%; p = 0.034), and increased cortical thickness (teriparatide, 22%; placebo, 3%; p = 0.012). These data show that teriparatide treatment of postmenopausal women with osteoporosis significantly increased cancellous bone volume and connectivity, improved trabecular morphology with a shift toward a more plate-like structure, and increased cortical bone thickness. These changes in cancellous and cortical bone morphology should improve biomechanical competence and are consistent with the substantially reduced incidences of vertebral and nonvertebral fractures during administration of teriparatide. [source] Daidzein but not other phytoestrogens preserves bone architecture in ovariectomized female rats in vivoJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 6 2008D. Somjen Abstract Ovariectomy of immature female rats, results in significant decrease of trabecular bone volume and in cortical bone thickness. Previously, we found that estradiol-17, (E2) restored bone structure of ovariectomized (Ovx) female rats to values obtained in intact sham-operated female rats. E2 also selectively stimulated creatine kinase (CK) specific activity a hormonal-genomic activity marker. In the present study, we compared the effects of E2 and the phytoestrogens: daidzein (D), biochainin A (BA), genistein (G), carboxy-derivative of BA (cBA), and the SERM raloxifene (Ral) in Ovx, on both histological changes of bones and CK, when administered in multiple daily injections for 2.5 months. Bone from Ovx rats, showed significant disrupted architecture of the growth plate, with fewer proliferative cells and less chondroblasts. The metaphysis underneath the growth plate, contained less trabeculae but a significant increased number of adipocytes in the bone marrow. D like E2 and Ral but not G, BA, or cBA, restored the morphology of the tibiae, similar to that of control sham-operated animals; the bony trabeculeae observed in the primary spongiosa was thicker, with almost no adipocytes in bone marrow. Ovariectomy resulted also in reduced CK, which in both epiphysis and diaphysis was stimulated by all estrogenic compounds tested. In summary, only D stimulated skeletal tissues growth and differentiation as effectively as E2 or Ral, suggesting that under our experimental conditions, D is more effective in reversing menopausal changes than any of the other isolated phytoestrogens which cannot be considered as one entity. J. Cell. Biochem. 103: 1826,1832, 2007. © 2007 Wiley-Liss, Inc. [source] Synovial fluid biomarker levels predict articular cartilage damage following complete medial meniscectomy in the canine kneeJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2002Cathy S. Carlson The purposes of this study were to document the histological changes present in the tibial plateaus 12 weeks after complete medial meniscectomy in dogs and to determine if synovial lavage fluid biomarker levels are predictive of the severity of joint damage. Twelve adult dogs underwent complete unilateral medial meniscectomy and synovial lavage fluid biomarker levels, including cartilage oligomeric matrix protein (COMP), keratan sulfate (5D4), 3B3(,), and 3B3(+), were measured serially at 4-week intervals. The dogs were euthanized 12 weeks after surgery and each medial and lateral tibial plateau from the meniscectomized and contralateral knees was graded histologically. Histological data were analyzed using principal components analysis, which resulted in 4 factors that explained 70% of the variation in the data. Factor 2 (weighted most heavily by subchondral bone thickness) and Factor 3 (representative of articular cartilage damage) were significantly affected by compartmental site (P < 0.01 for both). Both of these factors were highest in the medial tibial plateau of the meniscectomized knee, and Factor 3 was significantly higher in this site than in the medial tibial plateau of the contralateral knee (P < 0.01). Peak levels of all 4 synovial lavage fluid biomarkers occurred at 4 weeks post-meniscectomy and 4-week minus baseline levels of all biomarkers were significantly correlated with the Factor 3 scores. This study demonstrates that significant articular cartilage damage occurs relatively quickly following complete medial meniscectomy in dogs and establishes the content and criterion validity for these synovial fluid lavage biomarkers in canine meniscectomy as surrogate measures of articular cartilage damage. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Quantitative radiographic changes in the mandible and the tibia in systemically loaded rats fed a low-calcium dietORAL DISEASES, Issue 5 2000Y Morimoto The combined effect of the duration of loaded physical exercise and the percentage of calcium intake on the mandible and tibia were studied in developing male rats. For the loaded exercise, rats ran on a treadmill at a rate of 12 m per min for either 1 or 2 h per day. A total of 54 4-week-old male Wistar rats were randomly assigned to one of six groups. After 4 weeks of the diet and loaded exercise, the rats were killed and their mandibles and tibia were removed. Each individual bone was assessed by radiography and the radiographs were then used for measurements of cortical thickness, bone length and bone width. All radiographic images were analyzed using a computer-based scanner image analysis system. In addition, we measured the dry weight both of the tibia and mandible. The results demonstrated that significant differences in cortical thickness, bone length, bone width, and bone weight, both of the tibia and the mandible, were detectable between the normal diet group and the low-calcium diet group. Among the normal diet groups, significant differences were found in cortical thickness, bone length, bone width, and bone weight of the tibia, whereas no significant differences in either cortical bone thickness, bone length or bone weight of the mandible were detected. In contrast, among the low-calcium diet groups, no significant differences were detected in cortical thickness, bone length, bone width or bone weight for either the tibia or the mandible. Our results suggested that systemic exercise, such as running, promote the linear dimensions and the cortical thickness of the tibia in response to local stimuli. Furthermore, sufficient calcium intake appears to be necessary to allow the effect of systemic exercise on tibial bone growth to occur. In contrast, systemic loaded exercise does not promote either bone growth or development of the mandible even under conditions of sufficient calcium intake. [source] The effects of socioeconomic status on endochondral and appositional bone growth, and acquisition of cortical bone in children from 19th century Birmingham, EnglandAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2009Simon Mays Abstract Endochondral growth, appositional growth, and acquisition of cortical bone thickness in the femur are investigated in subadult skeletons (N = 43, dental age range birth to 12 years) from the 19th -century AD burial site of St. Martin's churchyard, Birmingham, England. Endochondral growth is monitored using diaphyseal femoral length. Appositional growth is monitored using radiographic midshaft mediolateral width and acquisition of cortical bone using combined mediolateral cortical thickness measured at the midshaft from radiographs. The methodology involves plotting these variables against dental age. Growth is compared in children of differing socioeconomic status. Higher and lower status individuals are identified in the assemblage by their burial in brick vaults in the case of the former and in earth-cut graves in the case of the latter. The relationships between bone dimensions and dental age are described using a polynomial regression procedure, and analysis of regression residuals is used to evaluate differences in bone dimension-for-dental age between the two status groups. Results show that lower socioeconomic status individuals had lower cortical thickness-for-dental age than those of higher status. This was interpreted as likely reflecting poorer nutrition in the children of lower socioeconomic backgrounds. There was no patterning with respect to socioeconomic status in femur diaphyseal length or midshaft width. The results support the idea that, for skeletal populations, growth in cortical thickness may be a more sensitive indicator of adverse conditions in childhood than growth in bone length or width. Am J Phys Anthropol, 2009. © 2009 Wiley-Liss, Inc. [source] Osseous Tissue Engineering With Gene Therapy for Facial Bone Reconstruction,THE LARYNGOSCOPE, Issue 7 2001William H. Lindsey MD Abstract Objective Facial osseous defects remain a major functional and esthetic challenge for the head and neck surgeon. Tissue engineering may provide advantageous alternatives to conventional therapies. The objective of the study was to evaluate the efficacy of gene therapy in the repair of osseous facial defects. Study Design Blinded, controlled, prospective animal experiment. Methods Thirty adult athymic nude rats were divided into five groups of six animals. Three groups were used as control subjects. Two groups were treated with 3.75 × 108 viral particles containing recombinant type 5 adenoviral vectors. One group received viruses that coded for ,-galactosidase production, another received viruses that coded for bone morphogenetic protein (BMP-2) production. After 120 days rats were examined at necropsy with precise planimetry, histological analysis of new bone growth, and radio-densitometric analysis of bone thickness. Results Radio-densitometric measurements showed that BMP-2,treated nude athymic rats had significantly enhanced osseous repair compared with control subjects when evaluated by both radio-densitometry and histological examination. Conclusion Gene therapy,treated, immunosuppressed rodents had an enhanced osteoinductive repair of a dorsal osseous nasal defect. [source] Extreme obesity due to impaired leptin signaling in mice does not cause knee osteoarthritisARTHRITIS & RHEUMATISM, Issue 10 2009Timothy M. Griffin Objective To test the hypothesis that obesity resulting from deletion of the leptin gene or the leptin receptor gene results in increased knee osteoarthritis (OA), systemic inflammation, and altered subchondral bone morphology. Methods Leptin-deficient (ob/ob) and leptin receptor,deficient (db/db) female mice compared with wild-type mice were studied, to document knee OA via histopathology. The levels of serum proinflammatory and antiinflammatory cytokines were measured using a multiplex bead immunoassay. Cortical and trabecular subchondral bone changes were documented by microfocal computed tomography, and body composition was quantified by dual x-ray absorptiometry. Results Adiposity was increased by ,10-fold in ob/ob and db/db mice compared with controls, but it was not associated with an increased incidence of knee OA. Serum cytokine levels were unchanged in ob/ob and db/db mice relative to controls, except for the level of cytokine-induced neutrophil chemoattractant (keratinocyte chemoattractant; murine analog of interleukin-8), which was elevated. Leptin impairment was associated with reduced subchondral bone thickness and increased relative trabecular bone volume in the tibial epiphysis. Conclusion Extreme obesity due to impaired leptin signaling induced alterations in subchondral bone morphology without increasing the incidence of knee OA. Systemic inflammatory cytokine levels remained largely unchanged in ob/ob and db/db mice. These findings suggest that body fat, in and of itself, may not be a risk factor for joint degeneration, because adiposity in the absence of leptin signaling is insufficient to induce systemic inflammation and knee OA in female C57BL/6J mice. These results imply a pleiotropic role of leptin in the development of OA by regulating both the skeletal and immune systems. [source] Vertical bone augmentation with fluvastatin in an injectable delivery system: a rat studyCLINICAL ORAL IMPLANTS RESEARCH, Issue 8 2009Yohei Jinno Abstract Objectives: HMG-CoA reductase inhibitors (statins) are widely used for hyperlipidemia. Previous studies demonstrate that statins stimulate bone morphogenetic protein-2 (BMP-2) expression and lead to bone formation. The aim of this study was to evaluate whether percutaneously injected statin with a novel statin delivery system achieved vertical bone augmentation. Material and methods: As experimental groups, atelocollagen-,-tricalcium phosphate (,TCP) composites containing 3.3 mg (low dose) or 6.7 mg (high dose) of fluvastatin were injected (one shot) subcutaneously over the calvarial periosteum of rats. The animals were then sacrificed 1, 2, and 4 weeks after injection. Vertically augmented bone was assessed by histomorphometric procedures, i.e., by measuring new bone thickness (NBT) and bone density (BD). Results: In control groups, no newly formed bone could be seen over the calvarial bone. In the experimental groups, in contrast, a large amount of newly formed bone could be seen over the preexisting calvarial bone. The newly formed bone was seen to be in direct contact with the preexisting bone. During the entire observation, significant NBT was observed in the experimental groups (P<0.05). At the final stage of observation (4 weeks), NBT was 66.7% (low-dose group) and 59.7% (high-dose group), while they were from 1% to 16.3% in the control groups. In the experimental groups, BD significantly increased in a time-dependent manner. Conclusion: Percutaneously applied fluvastatin (one shot) with a composite of ,TCP and collagen has great potential to augment the height of the bone. [source] Osteotomy and membrane elevation during the maxillary sinus augmentation procedureCLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2008A comparative study: piezoelectric device vs. conventional rotative instruments Abstract Objectives: The aim of the present study was to investigate in a randomized-controlled clinical trial the performance of rotary instruments compared with a piezoelectric device during maxillary sinus floor elevation. Materials and methods: Thirteen patients who required a bilateral maxillary sinus augmentation for implant,prosthetic rehabilitation were included in this study. A within-patient control study was carried out. The osteotomy for sinus access was performed on one side of the maxilla using the piezosurgery (test sites) and on the other side using conventional rotary diamond burs (control sites). The parameters recorded were as follows: bony window length (L), bony window height (H), bone thickness (T) and osteotomy area (A) , calculated by multiplying L and H. In addition, the time necessary for the osteotomy and sinus membrane elevation as well as the number of surgical complications were calculated. Results: The mean length and height of the bone window were similar in both groups. The osteotomy area (A) obtained by multiplying L and H was wider in the control group (151.2 ± 20.4 mm2) compared with the test group (137 ± 24.2 mm2). The time necessary for the osteotomy and the sinus membrane elevation with conventional instruments was 10.2 ± 2.4 min, while with the piezoelectric device it was 11.5 ± 3.8 min. Moreover, membrane perforation occurred in 30% of the maxillary sinuses in the test group and in 23% of the control group. None of the differences observed between the two groups reached a level of significance. Conclusions: Within the limits of the present study, it may be concluded that piezosurgery and conventional instruments did not show any differences in the clinical parameters investigated for the maxillary sinus floor elevation. [source] Horizontal ridge augmentation using autogenous block grafts and the guided bone regeneration technique with collagen membranes: a clinical study with 42 patientsCLINICAL ORAL IMPLANTS RESEARCH, Issue 4 2006Thomas Von Arx Abstract Objective: To analyze the clinical outcome of horizontal ridge augmentation using autogenous block grafts covered with anorganic bovine bone mineral (ABBM) and a bioabsorbable collagen membrane. Material and methods: In 42 patients with severe horizontal bone atrophy, a staged approach was chosen for implant placement following horizontal ridge augmentation. A block graft was harvested from the symphysis or retromolar area, and secured to the recipient site with fixation screws. The width of the ridge was measured before and after horizontal ridge augmentation. The block graft was subsequently covered with ABBM and a collagen membrane. Following a tension-free primary wound closure and a mean healing period of 5.8 months, the sites were re-entered, and the crest width was re-assessed prior to implant placement. Results: Fifty-eight sites were augmented, including 41 sites located in the anterior maxilla. The mean initial crest width measured 3.06 mm. At re-entry, the mean width of the ridge was 7.66 mm, with a calculated mean gain of horizontal bone thickness of 4.6 mm (range 2,7 mm). Only minor surface resorption of 0.36 mm was observed from augmentation to re-entry. Conclusions: The presented technique of ridge augmentation using autogenous block grafts with ABBM filler and collagen membrane coverage demonstrated successful horizontal ridge augmentation with high predictability. The surgical method has been further simplified by using a resorbable membrane. The hydrophilic membrane was easy to apply, and did not cause wound infection in the rare instance of membrane exposure. [source] Surgical advantages with ITI TE® implants placement in conjunction with split crest techniqueCLINICAL ORAL IMPLANTS RESEARCH, Issue 2 200518-month results of an ongoing prospective study Abstract: Implant rehabilitation of the edentulous maxilla may be somewhat problematic because of anatomic situations involving insufficient bone thickness. One approach in this situation is localized ridge augmentation with the split crest technique. This surgical approach allows the external cortical plate of the maxilla to be moved in a labial direction to gain an increase in width to introduce implants of appropriate diameter. This ongoing prospective study evaluated: (i) the surgical advantages that the new ITI TE® implants have showed compared with the ITI standard solid-screw implants when placed in conjunction with the split crest technique and (ii) the implant success rate associated with 42 ITI TE® implants and 40 ITI standard solid-screw implants placed in 40 patients in conjunction with the split crest technique. ITI TE® implants have shown direct and indirect advantages in reducing the risk of fracture of the labial cortical plate during all the three fundamental surgical steps of this technique: (a) the ridge expansion with osteotomes; (b) implant site preparation with drills and (c) implant insertion. The overall success rates of ITI TE® implants and standard screw implants were 100% and 95%, respectively. Based on the preliminary results of the present study, it can be concluded that ITI TE® implants inserted in conjunction with split crest technique seem to be a promising surgical procedure to treat selected anatomic situations involving insufficient maxillary bone thickness. Résumé La réhabilitation implantaire du maxillaire édenté peut être problèmatique à cause des situations anatomiques comportant une insuffisance de l'épaisseur osseuse. Une approche de cette situation est d'effectuer un épaississement du rebord localisé avec la technique du rebord osseux fendu. Cette approche chirurgicale permet au plateau cortical externe du maxillaire d'être déplacé en une direction linguale pour augmenter la largeur afin de pouvoir ensuite placer des implants d'un diamètre approprié. Cette étude prospective encore en cours a évalué 1) les avantages chirurgicaux des nouveaux implants ITI TE comparés aux implants ITI en vis solide ITI standard lorsqu'ils étaient placés en association avec cette technique de rebord osseux fendu et 2) le taux de succès implantaire associé avec 42 implants ITI TE et 40 implants vis solides ITI standard placés chez 40 patients en association avec cette technique de rebord osseux fendu. Les implants ITI TE ont montré des avantages directs et indirects en réduisant le risque de fracture de la corticale linguale durant les trois étapes chirurgicales fondamentales de cette technique : a) l'expansion du rebord alvéolaire avec les ostétomes, b) la préparation des sites implantaires avec les forets et c) l'insertion implantaire. Les taux de succès généraux des implants ITI TE et des implants vis standards étaient respectivement de 100 % et 95%. Basé sur le résultat préléminaire de cette étude, il peut être conclu que les implants ITI TE insérés en association avec la technique du rebord osseux fendu semble être un processus chirurgical prometteur pour traiter des situations anatomiques sélectionnées qui comportent une épaisseur osseuse insuffisante du maxillaire. Zusammenfassung Die Rekonstruktion einer zahnlosen Situation im Oberkiefer ist dann etwas problematischer, wenn anatomisch ungünstige Gegebenheiten wie zum Beispiel eine ungenügende vertikale Breite des Alveolarknochens besteht. Eine mögliche Vorgehensweise in dieser Situation ist die lokale Knochenaugmentation mittels Spaltung und Spreizung der Knochenkortikalis. Diese chirurgische Methode erlaubt uns, die äussere Kortikalis des Oberkiefers in labialer Richtung abzuspreizen und somit ein genügend breites Knochenbett zu erhalten, um Implantate mit dem geeigneten Durchmesser setzen zu können. Diese noch weiterverfolgte Langzeitstudie untersuchte: (i) die chirurgischen Vorteile, die uns das neue ITI TE-Implantat verglichen mit der Vollschraube des ITI-Standardimplantates in Verbindung mit der Kortikalisspreiztechnik bringt und (ii) die Implantaterfolgsrate von 42 ITI TE-Implantaten und 40 Vollschrauben der ITI-Standartimplantate, die man bei 40 Patienten in Verbindung mit der Kortikalisspreiztechnik gesetzt hat. Die ITI TE-Implantate zeigten direkte und indirekte Vorteile bei der Verminderung des Frakturrisikos in der labialen Kortikalisplatte während den drei grundlegenden Schritten dieser Technik: (a) Spreizung des Knochenkamms mit Osteotomen; (b) Vorbohren des Implantatbettes und (c) Eindrehen der Implantate. Die Erfolgsrate lag bei den ITI TE-Implantaten bei 100% und bei den Standartschraubenimplantaten bei 95%. Basierend auf diesen ersten Resultaten der Studie kann man schliessen, dass es sich bei ITI TE-Implantate, die in Verbindung mit der Kortikalisspreiztechnik eingesetzt worden waren, um eine vielversprechende chirugische Technik handelt, um ausgewählte anatomische Situationen, wie zu Beispiel eine ungenügende vertikale Breite des Alveolarknochens im Oberkiefer, zu behandeln. Resumen La rehabilitación con implantes del maxilar edéntulo puede ser un tanto problemática debido a situaciones anatómicas que comprenden situaciones de grosor óseo insuficiente. Un enfoque en esta situación, es el aumento localizado de la cresta con la técnica de cresta dividida. Este enfoque quirúrgico permite mover la placa cortical externa del maxilar en dirección labial para ganar un aumento en anchura para introducir implantes del diámetro apropiado. Este estudio prospectivo continuado evaluó: i) los avances quirúrgicos que los nuevos implantes ITI TE han mostrado en comparación con los implantes macizos roscados ITI estándar al colocarse en combinación con la técnica de cresta dividida y ii) el índice de éxito del implante asociado con 42 implantes ITI TE y 40 implantes macizos roscados estándar colocados en 40 pacientes en combinación con la técnica de cresta dividida. Los implantes ITI TE han mostrado ventajas directas e indirectas en reducir el riesgo de fractura de la placa cortical labial durante los tres pasos quirúrgicos fundamentales de esta técnica: a) expansión de la cresta con osteotomos; b) preparación del lecho implantario con fresas y c) inserción del implante. El índice total de éxito de los implantes ITI TE y de los implantes estándar roscados fue del 100% y del 95% respectivamente. Basado en los resultados preliminares del presente estudio, se puede concluir que los implantes ITI TE insertados en combinación con la técnica de cresta dividida parece ser un procedimiento quirúrgico prometedor para tratar situaciones anatómicas determinadas que conllevan un grosor óseo maxilar insuficiente. [source] | |||||||||||||