			Home About us Contact

Bone Chips (bone + chip)

Distribution by Scientific Domains

Medical Sciences	100%

Distribution within Medical Sciences

Implant Dentistry	50%
Periodontology	40%

Kinds of Bone Chips

autogenous bone chip

Selected Abstracts

Augmentation of Exposed Implant Threads with Autogenous Bone Chips: Prospective Clinical Study

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 4 2000
Göran Widmark DDS
ABSTRACT Background: Autogenous bone chips can be harvested during drilling of implant sites and may be used as a graft material for bone augmentation and coverage of exposed implant threads. Purpose: The aim of this prospective study was to evaluate the possibility of augmenting exposed implant threads with autogenous bone chips. Materials and Methods: Twenty-one consecutive patients treated with screw-shaped oral implants with exposed threads due to buccal fenestration or marginal defects were augmented with autogenous bone harvested with a bone trap during drilling of the implant site. Both marginal (9 sites) and fenestration defects (12 sites), with 4 to 14 exposed implant threads, were registered clinically and with photography. The number of exposed implant threads was measured before and at second-stage surgery 6 months after augmentation. Results: Complete bone coverage of the exposed implant threads was seen in 12 of the 21 implant sites. Six sites showed one to two remaining exposed threads, two showed about 40% coverage, and one showed flattening of the defect but with eight of nine exposed threads at 6 months follow-up. The mean bone gain was 81% in patients with a marginal defect and 82% in patients with a fenestration defect. Conclusion: The results from this clinical study show that it is possible to gain bone over exposed implant threads by augmentation with autogenous bone chips. Conclusion It is concluded that it is possible to achieve coverage of exposed implant threads by augmentation with autogenous bone chips harvested during drilling of implant sites. [source]

Effect of bone chip orientation on quantitative estimates of changes in bone mass using digital subtraction radiography

JOURNAL OF PERIODONTAL RESEARCH, Issue 3 2003
André Mol
Objectives:, To assess the effect of the orientation of arbitrarily shaped bone chips on the correlation between radiographic estimates of bone loss and true mineral loss using digital subtraction radiography. Methods:, Twenty arbitrarily shaped bone chips (dry weight 1,10 mg) were placed individually on the superior lingual aspect of the interdental alveolar bone of a dry dentate hemi-mandible. After acquiring the first baseline image, each chip was rotated 90 degrees and a second radiograph was captured. Follow-up images were created without the bone chips and after rotating the mandible 0, 1, 2, 4, and 6 degrees around a vertical axis. Aluminum step tablet intensities were used to normalize image intensities for each image pair. Follow-up images were registered and geometrically standardized using projective standardization. Bone chips were dry ashed and analyzed for calcium content using atomic absorption. Results:, No significant difference was found between the radiographic estimates of bone loss from the different bone chip orientations (Wilcoxon: P > 0.05). The correlation between the two series of estimates for all rotations was 0.93 (Spearman: P < 0.05). Linear regression analysis indicated that both correlates did not differ appreciably ( and ). Conclusion:, It is concluded that the spatial orientation of arbitrarily shaped bone chips does not have a significant impact on quantitative estimates of changes in bone mass in digital subtraction radiography. These results were obtained in the presence of irreversible projection errors of up to six degrees and after application of projective standardization for image reconstruction and image registration. [source]

Lipopolysaccharide alters decorin and biglycan synthesis in rat alveolar bone osteoblasts: consequences for bone repair during periodontal disease

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 3 2008
Helen C. Roberts
A prime pathogenic agent associated with periodontitis is lipopolysaccharide (LPS) derived from Porphyromonas gingivalis. This study investigated the effects of P. gingivalis LPS on osteoblasts, which are responsible for alveolar bone repair. Bone cells were obtained from explants of rat alveolar bone chips and cultured with 0,200 ng ml,1 of P. gingivalis LPS. Porphyromonas gingivalis LPS significantly increased cell proliferation and inhibited osteoblast differentiation, as judged by reduced alkaline phosphatase activity. Analysis of biglycan mRNA and protein levels indicated that P. gingivalis LPS significantly delayed the normally high expression of biglycan during the early stages of culture, which are associated with cell proliferation and early differentiation of progenitor cells. In the presence of P. gingivalis LPS, decorin expression by the alveolar bone cells was reduced during periods of culture relating to collagen fibrillogenesis and mineral deposition. Analysis of glycosaminoglycan chains conjugated to these proteoglycans suggested that in the presence of P. gingivalis LPS, dermatan sulfate persisted within the matrix. This study suggests that P. gingivalis LPS influences the expression and processing of decorin and biglycan in the matrix, altering alveolar bone cell activity and osteoblast phenotype development. The consequences of this altered expression in relation to hindering bone repair as part of the cycle of events during periodontal disease are discussed. [source]

The amount of newly formed bone in sinus grafting procedures depends on tissue depth as well as the type and residual amount of the grafted material

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 2 2005
Zvi Artzi
Abstract Objectives: Bone replacement substitutes are almost unavoidable in augmentation procedures such as sinus grafting. The objective of the present study was to evaluate the osteoconductive capability of two different scaffold fillers in inducing newly formed bone in this procedure. Material and Methods: Sinus floor augmentation and implant placement were carried out bilaterally in 12 patients. Bovine bone mineral (BBM) was grafted on one side and , -tricalcium phosphate (, -TCP) on the contralateral side. Both were mixed (1:1 ratio) with autogenous cortical bone chips harvested from the mandible by a scraper. Hard tissue specimen cores were retrieved from the augmented sites (at the previous window area) at 12 months. Decalcified sections were stained with haematoxylin,eosin and the fraction area of new bone and filler particles was measured. In addition to the effect of the filler on new bone formation, the latter was tested to determine whether it correlated with the tissue depth and residual amount of the grafted material. Results: Bone area fraction increased significantly from peripheral to deeper areas at both grafted sites in all cores: from 26.0% to 37.7% at the , -TCP sites and from 33.5% to 53.7% at the BBM-grafted sites. At each depth the amount of new bone in BBM sites was significantly greater than that in TCP sites. However, the average area fraction of grafted material particles was similar in both fillers and all depth levels (, -TCP=27.9,23.2% and BBM=29.2,22.6%, NS). A significant negative correlation was found between bone area fraction and particle area fraction at the middle (p=0.009) and deep (p=0.014) depths in the , -TCP sites, but not at the BBM sites. Conclusion: At 12 months post-augmentation, the two examined bone fillers, , -TCP and BBM, promoted new bone formation in sinus grafting but the amount of newly formed bone was significantly greater in BBM-grafted sites. However, both exhibited similar residual grafted material area fraction at this healing period. This could imply that BBM possesses better osteoconductive properties. [source]

Effect of bone chip orientation on quantitative estimates of changes in bone mass using digital subtraction radiography

A New Technique for Reconstruction of the Atrophied Narrow Alveolar Crest in the Maxilla Using Morselized Impacted Bone Allograft and Later Placement of Dental Implants

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2008
Per Holmquist DDS
ABSTRACT Background: In cases when the alveolar crest is too narrow to host an implant, lateral augmentation is required. The use of autogenous bone blocks harvested from the iliac crest is often demanded. One disadvantage is the associated patient morbidity. Purpose: The purpose of this study was to clinically and histologically evaluate the use of morselized impacted bone allograft, a novel technique for reconstruction of the narrow alveolar crest. Materials and Methods: Two patients with completely edentulous maxillae and one partially edentulous, with a mean age of 77 years (range 76,79 years) were included in the study. The alveolar crest width was <3 mm without possibility to place any implant. Bone grafts were taken from a bone bank in Gävle Hospital. Bone from the neck of femur heads was milled to produce bone chips. The milled bone was partially defatted by rinsing in 37°C saline solution. After compression of the graft pieces with a size of 15 mm (height), 30 mm (length), and 6 mm (width), they were then fit to adapt to the buccal surface of the atrophied alveolar crest. One piece was placed to the right and one to the left side of the midline. On both sides fibrin glue was used (Tisseel®, Baxter AG, Vienna, Austria) to stabilize the graft. After 6 months of graft healing, dental implants were placed, simultaneously biopsies were harvested and in one patient two oxidized microimplants were placed. At the time of abutment connection, microimplants were retrieved with surrounding bone for histology. Fixed screw-retained bridges were fabricated in mean of 7 months after implant surgery. Radiographs were taken before and after implant surgery and after 1 year of loading. Results: Sixteen implants with an oxidized surface were placed (TiUnite®, Nobel Biocare AB, Göteborg, Sweden). After 1 year of functional loading, all implants were clinically stable. The marginal bone loss was 1.4 mm (SD 0.3) after 1 year of loading. The histological examination showed resorption and subsequent bone formation on the allograft particles. There were no signs of inflammatory cell infiltration in conjunction with the allograft. The two microimplants showed bone formation directly on the implant surface. Conclusions: This study shows that morselized impacted bone allograft can be used to increase the width of the atrophied narrow alveolar crest as a good alternative to autogenous bone grafts in elderly patients. The histological examination of biopsies revealed a normal incorporation process and no signs of an immunological reaction. Further studies with larger samples are of important to be able to conclude if equal results can be obtained using morselized impacted bone allograft as for autogenous bone graft. [source]

Augmentation of Exposed Implant Threads with Autogenous Bone Chips: Prospective Clinical Study

Evaluation of a novel biphasic calcium phosphate in standardized bone defects.

CLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2007
A histologic, histomorphometric study in the mandibles of minipigs
Abstract: Objective: A novel biphasic calcium phosphate (CaP) granulate consisting of hydroxyapatite (HA) and ,-tricalciumphosphate (TCP) was compared with pure HA and pure TCP and with autograft as positive control. Materials and methods: Four standardized bone defects were prepared in both mandibular angles of 16 minipigs and grafted with autogenous bone chips, HA, HA/TCP (60% : 40%), or TCP. Histologic and histomorphometric analysis of bone formation and graft degradation followed healing periods of 2, 4, 8, and 24 weeks. Results: 2 weeks: more bone formation in defects filled with autograft than with the three CaP materials (P<0.05). 4 weeks: bone formation differed significantly (P<0.05) between all four materials (autograft>TCP>HA/TCP>HA). 8 weeks: more bone formation in defects with autograft and TCP than with HA/TCP (P<0.05), and HA/TCP had more bone formation than HA (P<0.05). 24 weeks: no difference in bone formation between the groups. Autograft and TCP resorbed quickly and almost completely over 8 weeks, whereas HA/TCP and HA showed limited degradation over 24 weeks. Conclusion: All defects healed with mature lamellar bone and intimate contact between bone and the remaining graft material. The rate of bone formation corresponded to the content of TCP in the CaP materials. [source]

Effect of donor characteristics, technique of harvesting and in vitro processing on culturing of human marrow stroma cells for tissue engineered growth of bone

CLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2005
Helge Bertram
Abstract: The aim of this study was to assess the effect of donor characteristics and the technique of harvesting and in vitro processing on the efficacy of culturing of human mesenchymal stem cells (hMSCs) for tissue engineered growth of bone. Cultures of hMSCs were derived from iliac crest bone marrow aspirates (21 donors, age 11,76) and from cancellous bone grafting material (32 donors, age 13,84). Age had no significant effect on the ability to isolate and culture hMSCs, although the failure rate was 55.6% in donors beyond the age of 60, while it varied between 14.3% and 22.2% in donors under 60 years of age. Male and female donors had comparable failure rates (27.3% and 28.6%, respectively). Culturing of hMSCs was successful in 90.4% of marrow aspirates from 21 donors and in 62.5% of cancellous bone specimens from 35 donors. This difference was statistically significant (P=0.023). Regression analysis confirmed that at simultaneous testing of the three variables, only the source of cells significantly affected the result (P=0.043). Morphological evaluation of the unfractionated primary population showed a change in cell shape of the adherent cells from a triangular into thin spindle-shaped elongated form, which remains until confluence. When the cultures were exposed to osteoinductive medium, various morphotypes expressing different levels of alkaline phosphatase and secreting different amounts of mineral were evident. Morphology of marrow stroma cells (MSCs) from marrow aspirates was not different from MSCs derived from cancellous bone specimens. Expression of osteogenic markers in MSCs as shown by PCR as well, did not differ between the two sources. It is concluded that marrow aspirates and cancellous bone specimens produce comparable populations of MSCs. However, bone marrow aspirates from donors under the age of 60 years rather than cancellous bone chips are favourable for isolation and expansion of hMSCs for tissue engineered growth of bone. Résumé Le but de cette étude a été d'analyser l'effet des caractéristiques du donneur et la technique de prélèvement et du processus in vitro sur l'efficacité des cultures des cellules souches mésenchymateuses humaines (hMSC) pour la croissance tissulaire en laboratoire de l'os. Les cultures de hMSC provenaient de la moelle osseuse de la crête iliaque (21 donneurs de 11 à 76 ans) et de matériel de greffe osseuse d'os spongieux (32 donneurs de 13 à 84 ans). L'âge n'avait aucun effet significatif sur l'habilitéà isoler et à mettre en culture les hMSC bien que le taux d'échec était de 56% chez les donneurs au-dessus de 60 ans et variait de 14 à 22% chez les donneurs en-dessous de 60 ans. Les hommes et les femmes avaient des taux d'échec comparables de respectivement 27 et 28%. La mise en culture des hMSC a réussi dans 90% des prélèvements de moelle et dans 63% dans les échantillons osseux spongieux. Cette différence était statistiquement significative (P=0,023). L'analyse de régression a confirmé qu'avec un test simultané des trois variables, seul la source de cellules avait un réel effet sur le résultat (P=0,043). L'évaluation morphologique de la population primaire non-fractionnée a montré un changement dans l'apparence des cellules adhérentes depuis un aspect triangulaire à une forme allongée en forme de fuseau qui restait jusqu'à confluence. Lorsque les cultures étaient exposées à un milieu ostéoinductif différents morphotypes exprimant différents niveaux de phosphatase alcaline et secrétant différentes quantitées de minéraux étaient mis en évidence. La morphologie des MSC des prélèvements de la moelle n'était pas différente des MSC provenant des spécimens osseux spongieux. L'expression des marqueurs ostéogéniques dans les MSC ne montrait par PCR aucune différence entre ces deux sources. Les prélèvements de moelle et les spécimens osseux spongieux produisent donc des populations comparables de MSC. Cependant, les aspirations de moelle de donneurs en-dessous de 60 ans plutôt que les chips osseux spongieux sont favorables pour l'isolation et l'expansion des hMSC pour la croissance osseuse en laboratoire. Zusammenfassung Es war das Ziel dieser Studie, den Einfluss von Spender-Merkmalen, Entnahmetechnik und in vitro -Behandlung bei der erfolgreichen Kultivierung von menschlichen mesenchymalen Stammzellen (hMSCs) für das gewebsgesteuerte Knochenwachstum zu untersuchen. Die Kulturen der hMSCs gewann man aus vom Beckenkamm aspiriertem Knochenmark (21 Spender, Alter 11,76) und von Spongiosa aus Spendermaterial (32 Spender, Alter 13,84). Das Alter hatte keinen signifikanten Einfluss auf die erfolgreiche Isolierung und Kultivierung von hMSCs, obgleich die Misserfolgsrate bei Spendern über 60 Jahren 55.6% betrug, währenddem sie bei Spendern unter 60 Jahren zwischen 14.3% und 22.2% variierte. Männer und Frauen hatten vergleichbare Misserfolgsraten (27.3%, beziehungsweise 28.6%). Die Kultivierung von hMSCs war bei 90.4% des aspirierten Marks von 21 Spendern und 62.5% der Spongiosa von 35 Spendern erfolgreich. Diese Differenz war statistisch signifikant (P=0.023). Die Regressionsanalyse bestätigte, dass von den drei gleichzeitig getesteten Variablen nur die Entnahmequelle der Zellen das Resultat signifikant beeinflusste (P=0.043). Die morphologische Untersuchung der unfraktionierten Primärpopulation zeigte bei den adhärenten Zellen eine Veränderung der Zellform von einer dreieckigen zu einer spindelförmigen länglichen Form. Diese blieb bis zu ihrem Zusammenwachsen erhalten. Wurden die Kulturen einem osteoinduktiven Einfluss ausgesetzt, entwickelten sich verschiedene Morphotypen, die auch verschiedene Mengen alkalischer Phosphatase und Mineralien ausschieden. Die Morphologie der MSCs aus dem aspirierten Knochenmark war nicht anders als diejenige von MSCs aus spongiösen Knochenproben. Die Ausscheidung von osteogenen Markern durch die MSCs, auch messbar durch den PCR, verhielt sich bei den Zellen aus beiden Quellen gleich. Man schloss daher, dass aspiriertes Knochenmark und Spongiosa vergleichbare Populationen von MSCs produzieren. Für die Isolation und Expansion von hMSCs zur gesteuerten Knochengewebsregeneration ist aspiriertes Knochenmark vorteilhafter als spongiöse Knochenchips und der Spendern ist von Vorteil jünger als 60 Jahre. Resumen La intención de este estudio fue valorar el efecto de las características del donante y de la técnica de recogida y del procesamiento in vivo sobre la eficacia del cultivo de células madre mesenquimales humanas (hMSCs) para crecimiento óseo por ingeniería tisular. Los cultivos de hMSCs se derivaron de aspirados de la médula ósea de la cresta iliaca (21 donantes, edad 11,76) y de material de injerto de hueso esponjoso (32 donantes, edad 13,84). La edad no tuvo un efecto significativo en la habilidad para aislar y cultivar hMSCs, aunque el índice de fracaso fue del 55.6% en donantes por encima de los 60 años, mientras que varió entre el 14.3% y el 22.2% en donantes por debajo de los 60 años. Los donantes varones y hembras tuvieron índices de fracaso comparables (27.3 y 28.6%, respectivamente). El cultivo de hMSCs tuvo éxito en el 90.4% de los aspirados medulares de 21 donantes y en 62.5% de los especímenes de hueso esponjoso de 35 donantes. Esta diferencia fue estadísticamente significativa (P=0.023). El análisis de regresión confirmó que en la prueba simultanea de las tres variables, solo el origen de las células afectó significativamente el resultado (P=0.043). La evaluación morfológica de la población primaria no fraccionada mostró un cambio en la forma celular de las células adherentes de triangular a una forma de huso fino elongado, que se mantiene hasta su confluencia. Cuando los cultivos se expusieron a un medio osteoconductivo se evidenciaron varios morfotipos manifestando diferentes niveles de fosfatasa alcalina y segregando diferentes cantidades de mineral. La morfología de las MSCs de los aspirados medulares no fue diferente de las MSCs derivadas de los especímenes de hueso esponjoso. La manifestación de marcadores osteogénicos en MSCs mostrado por PCR tampoco difirió entre las dos fuentes. Se concluye que los aspirados medulares y los especímenes de hueso esponjoso producen poblaciones comparables de MSCs. De todos modos, los aspirados de médula ósea de donantes menores de 60 años por encima de las virutas de hueso esponjoso son más favorables para el aislamiento y la expansión de hMSCs para crecimiento óseo por ingeniería tisular. [source]