The role of poly(acrylic acid) in conventional glass polyalkenoate cements

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Abstract

Glass polyalkenoate cements (GPCs) have been used in dentistry for over 40 years. These novel bioactive materials are the result of a reaction between a finely ground glass (base) and a polymer (acid), usually poly(acrylic acid) (PAA), in the presence of water. This article reviews the types of PAA used as reagents (including how they vary by molar mass, molecular weight, concentration, polydispersity and content) and the way that they control the properties of the conventional GPCs (CGPCs) formulated from them. The article also considers the effect of PAA on the clinical performance of CGPCs, including biocompatibility, rheological and mechanical properties, adhesion, ion release, acid erosion and clinical durability. The review has critically evaluated the literature and clarified the role that the polyacid component of CGPCs plays in setting and maturation. This review will lead to an improved understanding of the chemistry and properties of the PAA phase which will lead to further innovation in the glass-based cements field.

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On the mechanisms of biocompatibility.

David Williams (2008)

The manner in which a mutually acceptable co-existence of biomaterials and tissues is developed and sustained has been the focus of attention in biomaterials science for many years, and forms the foundation of the subject of biocompatibility. There are many ways in which materials and tissues can be brought into contact such that this co-existence may be compromised, and the search for biomaterials that are able to provide for the best performance in devices has been based upon the understanding of all the interactions within biocompatibility phenomena. Our understanding of the mechanisms of biocompatibility has been restricted whilst the focus of attention has been long-term implantable devices. In this paper, over 50 years of experience with such devices is analysed and it is shown that, in the vast majority of circumstances, the sole requirement for biocompatibility in a medical device intended for long-term contact with the tissues of the human body is that the material shall do no harm to those tissues, achieved through chemical and biological inertness. Rarely has an attempt to introduce biological activity into a biomaterial been clinically successful in these applications. This essay then turns its attention to the use of biomaterials in tissue engineering, sophisticated cell, drug and gene delivery systems and applications in biotechnology, and shows that here the need for specific and direct interactions between biomaterials and tissue components has become necessary, and with this a new paradigm for biocompatibility has emerged. It is believed that once the need for this change is recognised, so our understanding of the mechanisms of biocompatibility will markedly improve.

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The statistical mechanics of polymerized material

S Edwards (1967)

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Evidence of chemical bonding at biomaterial-hard tissue interfaces.

G Vanherle, L Hellemans, P Lambrechts … (2000)

For many years, glass-polyalkenoate cements have been described as possessing the unique properties of self-adherence to human hard tissues, such as bones or teeth. However, direct experimental evidence to prove the existence of chemical bonding has not been advanced. X-ray Photoelectron Spectroscopy (XPS) was used to analyze the chemical interaction of a synthesized polyalkenoic acid with enamel and synthetic hydroxyapatite. For both enamel and hydroxyapatite, the peak representing the carboxyl groups of the polyalkenoic acid was detected to have significantly shifted to a lower binding energy. De-convolution of this shifted peak disclosed two components with a peak representing unreacted carboxyl groups and a peak suggesting chemical bonding to hydroxyapatite. On average, 67.5% of the carboxyl groups of the polyalkenoic acid were measured to have bonded to hydroxyapatite. XPS of hydroxyapatite also disclosed its surface to be enriched in calcium and decreased in phosphorus, indicating that phosphorus was extracted at a relatively higher rate than calcium. Analysis of these data supports the mechanism in which carboxylic groups replace phosphate ions (PO4(3-)) of the substrate and make ionic bonds with calcium ions of hydroxyapatite. It is concluded that an ultrathin layer of a polyalkenoic acid can be prepared on a hydroxyapatite-based substrate by careful removal of non-bonded molecules. With this specimen-processing method, XPS not only provided direct evidence of chemical bonding, but also enabled us to quantify the percentages of functional groups of the polyalkenoic acids that bonded to calcium of hydroxyapatite.