Controlled Release from Dental Materials

Polyelectrolytes have been widely used for the preparation of controlled/sus-tained release of drugs. It is therefore not surprising that attempts have been made to use dental implants for the slow-release of antibiotics and fluorides. It 

The effect of variability in fluoride release between hand-mixed and cap-sulated systems was studied by Verbeeck et al. [266] who found that the mean value and variance of fluoride release were greater for the capsulated system than for the hand-mixed system. A two-process mechanism, consisting of a short-term elution (with a half life of nine hours) followed by diffusion controlled long-term release, for the release of F was suggested based on an empirical correlation of the data. The differences in the amounts of F released are attributed to the different mixing processes. 

Wilson and Combe [271] discuss a novel GIC which releases strontium, aluminum and boron, instead of fluoride. These elements are reported to have anticariogenic properties, and their release, unlike with fluoride, is claimed not to result in discoloration. 

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Photopolymerizable systems have received a lot of recent attention in biomaterial applications due to the ability to rapidly form a solid polymer (gel) from a liquid precursor solution (monomer or macromer) with spatial and temporal control under physiological conditions. The development of cytocompatible systems has provided the ability to form materials in the presence of proteins, cells, and tissues to allow for minimally invasive biomaterial-based therapies. In particular, photopolymerizable systems have been used extensively as dental restoratives, controlled microenvironments to study cellular behavior and develop tissue substitutes, and to encapsulate growth fartors and cytokines in a polymer matrix for controlled release applications. 

Lan, S.F., Kehinde, T., Zhang, X., Khajolia, S., Schmidtke, D.W., Starly, B., 2013. Controlled release of metronidazole from composite poly-epsilon-caprolactone/alginate (PC17 alginate) rings for dental implants. Dental Materials 29, 656—665. 

From dental repairs to controlled drug release or total organ/joint replacement, almost every human being on earth will be exposed to one biomaterial or another during their lifetime. Artificial organs are necessary to support part or all of their essential functions thereby improving quality of life. In biomaterial science, interaction between biomaterials and natural tissues is still an important subject. The informations are essential to aid the design of new biocompatible materials. 

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