A comparative study of ultrastructures of the interfaces between four kinds of surface‐active ceramic and bone

Abstract

The interfaces between four kinds of surface-active ceramic and bone were studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) using undecalcified specimens. The materials were Bioglass-type glass (Bioglass), Ceravital-type glass-ceramic (KGS), apatite- and wollastonite-containing glass-ceramic (A-W.GC) and hydroxyapatite (HA). Particles of these materials, ranging between about 100 and 300 microns in diameter, were implanted into rat tibiae, and specimens were prepared for observation at 8 weeks after implantation. All materials were observed to bond to bone through a collagen-free layer consisting of fine apatite crystals distinct from those in bone. The crystals of this apatite layer and those of bone were intermingled at their interface, suggesting chemical bonding. In Bioglass, which had only a glassy phase, several tens of microns of the material surface had changed to such an apatite layer. In KGS and A-W.GC, which had macrocrystals in the glassy phase, an intervening apatite layer about 0.5 micron thick was observed between the materials and bone. Furthermore, fine apatite crystals were also observed among the macrocrystals near the surface of the materials. In HA, which had no glassy phase, an intervening apatite layer was much less distinct and sometimes absent. These differences were considered to be attributable to the differences in chemical composition, crystallization, and solubility of the materials.

Development of highly functionalized ceramic biomaterials

“…Simple chemical treatment of titanium substrate with 30 vol % H 2 O 2 solution containing 5 mol·m ¹3 tantalum chloride (TaCl 5 ) also improved apatite formation ability in SBF. 16) An enhanced bonding property was observed in vivo for titanium substrate treated by H 2 O 2 solution containing TaCl 5 . 17) Apatite formation was induced by formation of a suitable titania hydrogel layer after the treatment.…”

“…Guidelines for controlling the crystalline phases and morphology of calcium phosphates under various conditions using pH, calcium ion concentration, and phosphate ion concentration were reported. The resulting calcium phosphate crystalline phases varied from HAp to DCPD or dicalcium phosphate anhydrous (DCPA, CaHPO 4 Figure 7 shows OCP formed in silica hydrogel under various pH and temperature conditions. The morphology of OCP changed from spherical to rod-or ribbon-like with increasing reaction temperature and decreasing pH, while the morphology of HAp changed from irregular to rod-like with increasing reaction temperature and decreasing pH.…”

Control of β-Tricalcium Phosphate Formation in Macroporous Phosphate Glass-Ceramic Composites

“…Bioglass Ò and -TCP have been well-known as biodegradable materials with high solubility. [7][8][9][10][11] Bioglass Ò , however, has a tendency to worry about its fragility and its toxicity, originating from high silicon-releasability. It is difficult to control the biodegradability of -TCP effectively.…”

Enhancement of Bone-Like Apatite Forming Abilities of Calcium Phosphate Ceramics in SBF by Autoclaving

“…[1][2][3] Bone-like hydroxyapatite b-HA layer intervenes between new bone and implanted surface-active ceramics such as HA, Cerabone A-Wଆand Bioglassଆ . 4,5 It was reported that HA bonded to bone directly or via a comparatively thin b-HA layer, and the b-HA layer with about 0.5 mm in thickness intervened between bone and Cerabone AWଆor Bioglassଆ . 5 On the other hand, new bone is directly formed on the surfaces of resorbable ceramics such as b-TCP after implantation in bone.…”

“…4,5 It was reported that HA bonded to bone directly or via a comparatively thin b-HA layer, and the b-HA layer with about 0.5 mm in thickness intervened between bone and Cerabone AWଆor Bioglassଆ . 5 On the other hand, new bone is directly formed on the surfaces of resorbable ceramics such as b-TCP after implantation in bone. These various reactions in the new bone formation depending on implanted ceramics were suspected to originate from differences in the chemical composition, crystallinity and resorbability of the ceramics in body.…”