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The dentin organic matrix - limitations of restorative dentistry hidden on the nanometer scale.

Bertassoni LE, Orgel JP, Antipova O, Swain MV - Acta Biomater (2012)

Bottom Line: Research has shown, however, that this interaction imposes less than desirable long-term prospects for current resin-based dental restorations.Finally, we discuss the relation of these complexly assembled nanostructures with the protease degradative processes driving the low durability of current resin-based dental restorations.We argue in favour of the structural limitations that these complexly organized and inherently hydrated organic structures may impose on the clinical prospects of current hydrophobic and hydrolyzable dental polymers that establish ultrafine contact with the tooth substrate.

View Article: PubMed Central - PubMed

Affiliation: Biomaterials Science Research Unit, Faculty of Dentistry, University of Sydney, United Dental Hospital, NSW, Australia. luiz.bertassoni@sydney.edu.au

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Spacefilling longitudinal (top) and cross-sectional (bottom) representations of the progressive hydration of the Gly-Ala peptide as seen in the crystal structure of the collagen molecule [72]. Each colour represents one peptide chain of the triple helix, whereas the water molecules are shown in blue. (A) A view of the molecule without water. Incorporation of the (B) first, (C) second and (D) third shells of water molecules. Water molecules are either directly hydrogen bonded to carbonyl, hydroxyl or even amide groups on the peptide surface or hydrogen bonded to the first or second shells of water molecules.
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f0025: Spacefilling longitudinal (top) and cross-sectional (bottom) representations of the progressive hydration of the Gly-Ala peptide as seen in the crystal structure of the collagen molecule [72]. Each colour represents one peptide chain of the triple helix, whereas the water molecules are shown in blue. (A) A view of the molecule without water. Incorporation of the (B) first, (C) second and (D) third shells of water molecules. Water molecules are either directly hydrogen bonded to carbonyl, hydroxyl or even amide groups on the peptide surface or hydrogen bonded to the first or second shells of water molecules.

Mentions: A single collagen molecule consists of three polypeptide chains composed of two α1 and one α2 sequences. The resulting molecular unit has a mass of about 285 kDa and is approximately 1.4 nm wide and 300 nm long. The basic triple-helical conformation consists of three closepacked supercoiled helices, which requires a glycine residue at every third position in the polypeptide chain [60]. This results in a (X–Y–Gly)n repeating pattern in which the X and Y positions are frequently occupied by proline and 4-hydroxyproline residues, respectively [62,72] (Fig. 1). The resulting polypeptide chain, therefore, assumes a left-handed helical conformation with about three residues per turn [60]. The assembled triple-helical molecular structure, on the other hand, is constituted by three parallel chains which wind around each other with a gentle right-handed supertwist to form the resulting molecular unit (Fig. 5).


The dentin organic matrix - limitations of restorative dentistry hidden on the nanometer scale.

Bertassoni LE, Orgel JP, Antipova O, Swain MV - Acta Biomater (2012)

Spacefilling longitudinal (top) and cross-sectional (bottom) representations of the progressive hydration of the Gly-Ala peptide as seen in the crystal structure of the collagen molecule [72]. Each colour represents one peptide chain of the triple helix, whereas the water molecules are shown in blue. (A) A view of the molecule without water. Incorporation of the (B) first, (C) second and (D) third shells of water molecules. Water molecules are either directly hydrogen bonded to carbonyl, hydroxyl or even amide groups on the peptide surface or hydrogen bonded to the first or second shells of water molecules.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3473357&req=5

f0025: Spacefilling longitudinal (top) and cross-sectional (bottom) representations of the progressive hydration of the Gly-Ala peptide as seen in the crystal structure of the collagen molecule [72]. Each colour represents one peptide chain of the triple helix, whereas the water molecules are shown in blue. (A) A view of the molecule without water. Incorporation of the (B) first, (C) second and (D) third shells of water molecules. Water molecules are either directly hydrogen bonded to carbonyl, hydroxyl or even amide groups on the peptide surface or hydrogen bonded to the first or second shells of water molecules.
Mentions: A single collagen molecule consists of three polypeptide chains composed of two α1 and one α2 sequences. The resulting molecular unit has a mass of about 285 kDa and is approximately 1.4 nm wide and 300 nm long. The basic triple-helical conformation consists of three closepacked supercoiled helices, which requires a glycine residue at every third position in the polypeptide chain [60]. This results in a (X–Y–Gly)n repeating pattern in which the X and Y positions are frequently occupied by proline and 4-hydroxyproline residues, respectively [62,72] (Fig. 1). The resulting polypeptide chain, therefore, assumes a left-handed helical conformation with about three residues per turn [60]. The assembled triple-helical molecular structure, on the other hand, is constituted by three parallel chains which wind around each other with a gentle right-handed supertwist to form the resulting molecular unit (Fig. 5).

Bottom Line: Research has shown, however, that this interaction imposes less than desirable long-term prospects for current resin-based dental restorations.Finally, we discuss the relation of these complexly assembled nanostructures with the protease degradative processes driving the low durability of current resin-based dental restorations.We argue in favour of the structural limitations that these complexly organized and inherently hydrated organic structures may impose on the clinical prospects of current hydrophobic and hydrolyzable dental polymers that establish ultrafine contact with the tooth substrate.

View Article: PubMed Central - PubMed

Affiliation: Biomaterials Science Research Unit, Faculty of Dentistry, University of Sydney, United Dental Hospital, NSW, Australia. luiz.bertassoni@sydney.edu.au

Show MeSH
Related in: MedlinePlus