Micromechanical Property Recovery of Human Carious Dentin Achieved with Colloidal Nano-β-tricalcium Phosphate

Abstract

Reconstitution of carious dentin has been recognized as difficult, because it progresses by loss of collagen polymerization and by demineralization under acidic conditions. Recently, colloidal alkaline nano-calcium phosphate, prepared by electrical discharge in a buffered physiological saline solution, has been shown to be effective in the formulation of a bone-like biocomposite by simply being mixed with acidic collagen solution. It was hypothesized that colloidal calcium phosphate was suitable for the reconstitution of carious dentin. Natural caries lesions in dentin from permanent teeth were exposed to colloidal hydroxyapatite and β-tricalcium phosphate for 10 days. The micromechanical properties of these tissues were evaluated by nano-indentation. The elastic modulus of human carious dentin improved after samples were immersed in colloidal β-tricalcium phosphate. The mineral density of carious dentin exposed to β-tricalcium phosphate increased more than that immersed in hydroxyapatite. However, since it was not directly proportional to micromechanical recovery, mineral density alone was not a sufficient indicator of mechanical behavior.

Get full access to this article

View all access options for this article.

References

Arends J, Ruben JL, Inaba D -1997-. Major topics in quantitative micro-radiography of enamel and dentin: R parameter, mineral distribution visualization, and hyper-remineralization. Adv Dent Res 11:403–414.

He G, Dahl T, George A, Veis A -2003-. Nucleation of apatite crystals in vitro by self-assembled dentin matrix protein 1. Nat Mater 2:552–557.

He LH, Fujisawa N, Swain MV -2006-. Elastic modulus and stress-strain response of human enamel by nano-indentation. Biomaterials 27:4388–4398.

Kidd EAM, Joyston-Bechal JS -1997-. Essentials of dental caries, the disease and its management. 2nd ed. New York: Oxford University Press.

Kinney JH, Habelitz S, Marshall SJ, Marshall GW -2003a-. The importance of intrafibrillar mineralization of collagen on the mechanical properties of dentin. J Dent Res 82:957–961.

Kinney JH, Marshall SJ, Marshall GW -2003b-. The mechanical properties of human dentin: a critical review and re-evaluation of the dental literature. Crit Rev Oral Biol Med 14:13–29.

Kurashina K, Hirano M, Kotani A, Klein CP, de Groot K -1997-. In vivo study of calcium phosphate cements: implantation of an alpha-tricalcium phosphate/dicalcium phosphate dibasic/tetracalcium phosphate monoxide cement paste. Biomaterials 18:539–543.

Mishra P, Palamara JEA, Tyas MJ, Burrow MF -2006-. Effect of loading and pH on the subsurface demineralization of dentin beams. Calcif Tissue Int 79:273–277.

Oliver WC Jr, Pharr GM -2004-. Measurement of hardness and elastic modulus by instrumented indentation: advances in understanding and refinements to methodology. J Mater Res 19:3–20.

10.

Perkin KK, Turner JL, Wooley KL, Mann S -2005-. Fabrication of hybrid nanocapsules by calcium phosphate mineralization of shell cross-linked polymer micelles and nanocages. Nano Lett 5:1457–1461.

11.

Saito M, Fujii K, Marumo K -2006-. Degree of mineralization-related collagen crosslinking in the femoral neck cancellous bone in cases of hip fracture and controls. Calcif Tissue Int 79:160–168.

12.

Shibata Y, Takashima H, Yamamoto H, Miyazaki T -2004-. Functionally gradient bonelike hydroxyapatite coating on a titanium metal substrate created by a discharging method in HBSS without organic molecules. Int J Oral Maxillofac Implants 19:177–183.

13.

Shibata Y, Yamamoto H, Miyazaki T -2005-. Colloidal β-tricalcium phosphate prepared by discharge in a modified body fluid facilitates synthesis of collagen composites. J Dent Res 84:827–831.

14.

Suppa P, Ruggeri A Jr, Tay FR, Prati C, Biasotto M, Falconi M, et al. -2006-. Reduced antigenicity of type I collagen and proteoglycans in sclerotic dentin. J Dent Res 85:133–137; erratum in J Dent Res 85:384, 2006.

15.

Takashima H, Shibata Y, Kim TY, Miyazaki T -2004-. Hydroxyapatite coating on a titanium metal substrate by a discharging method in modified artificial body fluid. Int J Oral Maxillofac Implants 19:66–72.

16.

Tjäderhane L, Larjava H, Sorsa T, Uitto VJ, Larmas M, Salo T -1998-. The activation and function of host matrix metalloproteinases in dentin matrix breakdown in caries lesions. J Dent Res 77:1622–1629.

17.

Yamaguchi K, Miyazaki M, Takamizawa T, Inage H, Moore BK -2006-. Effect of CPP-ACP paste on mechanical properties of bovine enamel as determined by an ultrasonic device. J Dent 34:230–236.

18.

Yamamoto H, Shibata Y, Tachikawa T, Miyazaki T -2006-. In vivo performance of two different hydroxyapatite coatings on titanium prepared by discharging in electrolytes. J Biomed Mater Res B Appl Biomater 78:211–214.

19.

Zhao F, Yin Y, Lu W, Leong J, Zhang W, Zhang J, et al. -2002-. Preparation and histological evaluation of biomimetic three-dimensional hydroxyapatite/chitosan-gelatin network composite scaffolds. Biomaterials 23:3227–3234.

Supplementary Material

Please find the following supplemental material available below.

For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.

For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.

0.00 MB

0.40 MB