Bone‐bonding ability of P₂O₅‐Free CaO · SiO₂ glasses

Abstract

An apatite- and wollastonite-containing glass-ceramic (A.W-GC) has been reported to form a tight bond with living bone through an apatite layer formed on its surface. This layer is considered to be formed by dissolution of Ca2+ and HSiO3- ions from the glass-ceramic into the surrounding body fluids. In order to confirm this proposed mechanism for the surface reaction of A.W-GC, three kinds of glass in the systems CaO-SiO2, CaO-SiO2-CaF2, and CaO-SiO2-P2O5 were implanted into the tibiae of rabbits for 3 or 8 weeks. Contact microradiography and SEM-EPMA showed that all three kinds of glass formed a Ca,P-rich layer in combination with a Si-rich layer on their surfaces within 3 weeks and formed a direct bond with bone via these layers. The detaching test, performed 8 weeks after implantation, showed that the loads required to detach the implants from the bone were almost equal for the phosphorus-free and the phosphorus-containing glasses. It was concluded that even P2O5-free CaO.SiO2 glass formed a Ca,P-rich layer on its surface and bonded tightly with living bone. If glasses and glass-ceramics release at least Ca2+ and HSiO3- ions, this would be sufficient for them to form the Ca,P-rich layer on their surfaces in vivo, enabling them to bond directly with bone.

Morphological and chemical analysis of different precipitates on mineral trioxide aggregate immersed in different fluids

“…This type of precipitate formation was characteristic of the pH-dependent autocatalytic transformation of metastable ACP phase into an apatite phase 18) . The formation of ACP on MTA could serve as a strong indicator of the biocompatibility and bioactivity of MTA, chiefly because the surface precipitation of biocompatible materials might be the basis for the bioactivity of calcium silicate-containing biomaterials 26,27) . Precipitate formation has also been reported to occur along the MTA-dentin interface 8,15,17,18) , which meant it might play a pivotal role in providing MTA with good sealing ability as an endodontic material.…”

In Vitro Evaluation of Silicate Based Bioactive Glass

“…Biomaterials are broadly classified as bio inert, bioactive and bio restorable [6]. Most of the bioinert materials are metals made up of Al 2 O 3 , ZrO 2 etc [7]. Bioinert materials bonding at the host tissue is very minimal almost inert [8], [9], [10].…”

Bioactivity of Strontium Doped Boro phosphate Disordered Glass

“…Hench and Anderson successfully explained the reactions occurred on the surface of bioactive glass when immersed in simulated body fluid. They are leaching and formation of silanols, dissolution of the glass network, silica gel polymerization, and then formation of calcium phosphate rich layer on the surface [3,4,14,15]. This layer finally crystallized to a hydroxyl carbonate apatite later.…”

“…The National Institute of Health Consensus Development Conference defined a bioactive material as "any substance or combination of substances, synthetic or natural in origin, which can be used for any period of time, or as a whole or as a part of a system which treats, augments, or replaces any tissue, organ or function of the body" [2,3]. After the great invention of first bioactive glass with composition 24.5Na 2 O-24.5CaO-6P 2 O 5 -45SiO 2 in wt% by Hench and his colleagues in 1969 many researchers are focussing on the field of bioactive materials to prepare new glasses or glass ceramics with new composition to enhance the properties of existing glasses [4]. Due to their biocompatibility and bioactivity bioactive glasses are used as implant materials to repair or replace deceased or damaged human body parts [5,6].…”