A Coralline Hydroxyapatite Bone Graft Substitute

Holmes, Ralph E.; Mooney, Vert; Bucholz, Robert W.; Tencer, Allan F.

doi:10.1097/00003086-198409000-00036

Cited by 260 publications

(137 citation statements)

References 0 publications

Supporting

Mentioning

126

Contrasting

Unclassified

Order By: Relevance

“…8 It is not surprising that the physical properties, such as the mechanical behaviour and the pore architecture, of the various porous calcium-phosphate products vary widely. [1][2][3]9,10 The potential of these materials has been recognised for some years, 6,7,[11][12][13] and there have been a number of investigations into the effect of pore structure on the repair process. 6 -12,14 -20 However, because of varying methods and degrees of quantification in both the pore structure and the volume or rate of bone apposition, there is still much confusion about the mechanisms behind bone ingrowth, or osseointe-gration, within macroporous structures.…”

Section: Introductionmentioning

confidence: 99%

“…6 -12,14 -20 However, because of varying methods and degrees of quantification in both the pore structure and the volume or rate of bone apposition, there is still much confusion about the mechanisms behind bone ingrowth, or osseointe-gration, within macroporous structures. A pore size Ͼ 100 m is often cited as a minimum requirement for healthy, sustainable bone ingrowth 7,9,11 and many studies report a dependence between volume or rate of integration and pore size. 7,9,11,12,14,16 However, other researchers promote the importance of additional structural parameters, such as pore morphology, percent porosity, and pore connectivity, 6,[17][18][19][20] whereas a minority dispute the role of structure at all.…”

Section: Introductionmentioning

confidence: 99%

“…As with osseointegration, the mechanical properties of a ceramic foam are highly dependent on both porosity and structural architecture. 9,10 Although faster ingrowth is favored by a more porous, interconnected structure, denser ceramics have better mechanical integrity. Biomechanical testing of retrieved implants has shown that newly integrated bone has a significant reinforcing effect on porous ceramic bone graft substitute materials, 20,21 and testing of longer term implants has generally shown retention of this conferred mechanical integrity.…”

Section: Introductionmentioning

confidence: 99%

“…Biomechanical testing of retrieved implants has shown that newly integrated bone has a significant reinforcing effect on porous ceramic bone graft substitute materials, 20,21 and testing of longer term implants has generally shown retention of this conferred mechanical integrity. 9,12,13,22 Thus, for clinical application, a ceramic bone graft substitute should have sufficient mechanical integrity to survive the implantation procedure and attain positional stability while maintaining its open porous structure before integration.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Mediation of bone ingrowth in porous hydroxyapatite bone graft substitutes

Hing

Best

Tanner

et al. 2003

J Biomedical Materials Res

193

137

View full text Add to dashboard Cite

Abstract:Previous investigations have shown that both the early biological response and the mechanical properties of a porous hydroxyapatite bone graft substitute are highly sensitive to its pore structure. The objective of this study was to evaluate whether the pore structure continued to influence bone integration in the medium to long term. Two screened batches of porous hydroxyapatite (PHA) designated as batch A and batch B, with porosities of ϳ60 and 80%, respectively, were selected for this study and implanted for periods of 5, 13, and 26 weeks into the lower femur of New Zealand White rabbits. Histomorphometric analysis of the absolute volume of bone ingrowth within batch A and B implants from 5 to 26 weeks showed that the absolute volume of bone ingrowth was consistently lower in batch A (10 -21%), compared to batch B implants (24 -31%). However, when the volume of bone ingrowth was normalised for the available pore space, this difference was reduced (23-47% and 32-42% for batches A and B, respectively). These observations suggest that differences in the volume of bone ingrowth initially depended on pore interconnectivity rather than pore size, whereas the volume or morphology of the PHA influenced the volume and morphology of bone ingrowth at later time points. Compression testing showed that bone ingrowth had a strong reinforcing effect on PHA bone graft substitutes, and a strong correlation was identified between mechanical properties and the absolute volume of ingrowth for both batches A and B. Furthermore, at 13 and 26 weeks, there was no significant variation in the ultimate compressive strength of integrated batch A and B implants. This similarity in ultimate mechanical properties indicated that the absolute volume of ingrowth may be mediated by the PHA structure through its impact on the dynamics of the local biomechanical environment. The results of push-out testing showed that fixation of PHA bone graft substitutes was independent of density within the range studied, with no significant difference in the interfacial shear stress between batches A and B at each time point throughout the study.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Mediation of bone ingrowth in porous hydroxyapatite bone graft substitutes

Hing

Best

Tanner

et al. 2003

J Biomedical Materials Res

193

137

View full text Add to dashboard Cite

show abstract

“…Thus, the N-surface accelerated the rate of crystal nucleation. In contrast, the P-surface was surrounded with anions such as HPO [2][3][4] , HCO 3-, and Cl -, and decelerated the rate of crystal nucleation. 13) Figure 6 shows SEM images of a pore 0.5 mm from the 0-surface, N-surface, and P-surface of HA disks after immersion in SBF for 5 d. It was found that bone-like apatite crystals were observed only on the polarized disks and not observed on the non-polarized disks.…”

Section: Jcs Japanmentioning

confidence: 96%

Electrovector effect on bone-like apatite crystal growth on Inside pores of polarized porous hydroxyapatite ceramics in simulated body fluid

Iwasaki

Tanaka

Nakamura

et al. 2008

J. Ceram. Soc. Japan

View full text Add to dashboard Cite

Porous hydroxyapatite (HA) disks and blocks with interconnecting pores (pore size150 mm, interconnecting window size 30 mm, and porosity75) were polarized and bone-like apatite formations on the pore surfaces were investigated by immersion test using simulated body fluid (SBF) to estimate the electrovector effect in porous bodies. Thermally stimulated depolarization current (TSDC) measurements were used to estimate the stored charges of polarized porous HA disks and blocks as 11 and 7 mC cm -2 , respectively, demonstrating that both the porous disks and blocks were successfully polarized. After immersion in SBF for 14 d, bone-like apatite formations within the pores were observed in the polarized and non-polarized HA disks and blocks. Based on scanning electron microscopic (SEM) images of the pores located around the center of the disks and the blocks (inside-pores), formation of bone-like apatite was accelerated in the polarized HA compared with that in the non-polarized HA. Although the weight of the polarized and non-polarized porous HA increased linearly with immersion time regardless of shape, the rate of weight change of the polarized HA was greater than that of the non-polarized HA. It was demonstrated that the electric charges on the inside-pore surface of porous HA have a positive effect on the formation of bone-like apatite crystals.

show abstract

Tibial segmental defect repair: Chondrogenesis and biomechanical strength modulated by basic fibroblast growth factor

et al. 1997

View full text Add to dashboard Cite

Background: The effect of recombinant human basic fibroblast growth factor (bFGF) on cartilage development and bone biomechanical strength during healing of a tibial segmental defect was studied in the rat. Two reports on the effect of basic FGF administration during fracture healing and several reports on the effects of acidic FGF have documented different responses of callus cartilage to this important growth factor. This is the first report of the effect of bFGF on cartilage formation in the healing of a grafted segmental defect in the rat. Methods The tibiae of 80 male rats underwent segmental resection of the mid‐diaphyseal region. One‐half of this group consisted of controls that received insertion of an intramedullary wire with a coralline hydroxyapatite graft and Gelfoam without bFGF. The tibiae of the other half were treated identically but had the Gelfoam impregnated with 1 μg bFGF. Animals were killed at 2, 4, and 8 weeks postoperatively. Histological sections were stained with toluidine blue to differentiate the cartilage. Areas of metachromatically stained extracellular matrix, cell areas, cell size, and cellularity were quantified by using image analysis. Unfixed treated and control tibiae were tested for bone failure strength by using four‐point bending on an Instron machine. Results Control bone failure strength was significantly greater than bFGF‐treated bones at 2 weeks and energy‐to‐failure was significantly decreased in treated bones at 2 weeks. Although strength increased with time in all groups, treated groups at 4 and 8 weeks did not differ from controls. Basic FGF treatment promoted an increase in the development of normal hyaline cartilage and vasculogenesis at 2 weeks as compared with controls. Total cartilage declined over time in all groups. Average cell size and cell number did not change with either treatment or time. Bone formation and healing was equivalent in treated and control groups at 8 weeks. Conclusions The results indicate that bFGF released directly and initially but not continuously exerts a transient positive effect on hyaline cartilage formation at the expense of repair site strength and does not accelerate healing. Anat. Rec. 248:198–204, 1997. © 1997 Wiley‐Liss, Inc.

show abstract

A Coralline Hydroxyapatite Bone Graft Substitute

Cited by 260 publications

References 0 publications

Mediation of bone ingrowth in porous hydroxyapatite bone graft substitutes

Mediation of bone ingrowth in porous hydroxyapatite bone graft substitutes

Electrovector effect on bone-like apatite crystal growth on Inside pores of polarized porous hydroxyapatite ceramics in simulated body fluid

Tibial segmental defect repair: Chondrogenesis and biomechanical strength modulated by basic fibroblast growth factor

Contact Info

Product

Resources

About