The control of hydroxyapatite crystal initiation and growth during enamel development is thought to be mediated via the proteins of the extracellular matrix. However, the precise nature of these matrix-mineral interactions remains obscure. The aim of the present study was to use a combination of atomic and chemical force microscopy to characterize developing enamel crystal surfaces and to determine their relationship with endogenous enamel matrix protein (amelogenin). The results show regular and discrete domains of various charges or charge densities on the surfaces of hydroxyapatite crystals derived from the maturation stage of enamel development. Binding of amelogenin to individual crystals at physiological pH was seen to be coincident with positively charged surface domains. These domains may therefore provide an instructional template for matrix-mineral interactions. Alternatively, the alternating array of charge on the crystal surfaces may reflect the original relationship with, and influence of, matrix interaction with the crystal surfaces during crystal growth.
Akita H., Fukae M., Shimoda S., Aoba T. ( 1992). Localisation of glycosylated matrix proteins in secretory porcine enamel and their possible functional roles in enamel mineralisation . Arch Oral Biol37:953-962.
2.
Aoba T., Moreno EC (1991). Structural relationship of amelogenin proteins to their regulatory function of enamel mineralisation. Am Chem Soc444:85-106.
3.
Bartlett JD, Simmer JP, Xue J., Margolis HC, Moreno EC (1996). Molecular cloning and mRNA tissue distribution of a novel matrix metalloproteinase isolated from porcine enamel organ. Gene183:123-128.
4.
Brookes SJ, Robinson C., Kirkham J., Bonass WA (1995). Biochemistry and molecular biology of amelogenin proteins of developing enamel. Arch Oral Biol40:1-14.
5.
Butt H., Jaschke M., Ducker W. (1995). Measuring surface forces in aqueous electrolyte solution with the atomic force microscope. Bioelectrochem Bioenerget38:191-201.
6.
Chander S., Fuerstenau DW (1984). Solubility and interfacial properties of hydroxyapatite: a review. In: Adsorption on and surface chemistry of hydroxyapatite . Misra DN, editor. New York: Plenum Press, pp. 29-49.
7.
Daculsi G., Kerebel B. (1978). High resolution electron microscope study of human enamel crystallites: size, shape and growth. J Ultrastruct Res65:163-172.
8.
Fincham AG, Moradian-Oldak J. (1995). Recent advances in amelogenin biochemistry. Connect Tissue Res32:119-124.
9.
Fincham AG, Moradian-Oldak J., Simmer JP, Sarte P., Lau EC, Diekwisch T., et al. (1994). Self-assembly of a recombinant amelogenin protein generates supramolecular structures. J Struct Biol112:103-109.
10.
Hillier A., Kim S., Bard A. ( 1996). Measurement of double layer forces at the electrode/electrolyte interface using the atomic force microscope: potential and anion dependent interactions. J Phys Chem100:18808-18817.
11.
Ikai A. ( 1996). STM and AFM of bio-organic molecules and structures. Surf Sci Rep26:263-332.
12.
Kirkham J., Brookes SJ, Shore RC, Bonass WA, Smith Dam, Wallwork ML, et al. (1998). Atomic force microscopy studies of crystal surface topology during enamel development. Connect Tissue Res39:91-100.
13.
Kirkham J., Brookes SJ, Zhang J., Wood SR, Shore RC, Smith Dam, et al. (2000). Effect of experimental fluorosis on the surface topography of developing enamel crystals. Caries Res35:50-59.
14.
Mafe S., Manzanares JA, Reiss H., Thomann JM, Gramain P. (1996). Model for the dissolution of calcium hydroxyapatite powder. J Phys Chem96:861-866.
15.
Moradian-Oldak J., Simmer JP, Lau EC, Sarte PE, Slavkin HC, Fincham AG (1994). Detection of monodisperse aggregates of a recombinant amelogenin by dynamic light scattering. Biopolymers34:1339-1347.
16.
Noy A., Frisbie C., Rozsnyai L., Wrighton M., Lieber CM (1995). Chemical force microscopy: exploiting chemically-modified tips to quantify adhesion, friction and functional group distributions in molecular assemblies. J Am Chem Soc117:7943-7951.
17.
Noy A., Vezenov DV, Lieber CM (1997). Chemical force microscopy. Ann Rev Mater Sci27:381-421.
18.
Robinson C., Fuchs P., Weatherell JA (1981). The appearance of developing rat incisor enamel using a freeze-fracturing technique. J Cryst Growth53:160-165.
19.
Robinson C., Kirkham J., Stonehouse NJ, Shore RC (1989). Control of crystal growth during enamel maturation . Connect Tissue Res22:139-145.
20.
Robinson C., Kirkham J., Brookes SJ, Shore RC (1992). The role of albumin in developing rodent dental enamel: a possible explanation for white spot hypoplasia. J Dent Res71:1270-1274.
21.
Robinson C., Kirkham J., Shore RC, Brookes SJ, Bonass WA (1995). Role of the extracellular matrix in enamel development . In: Dental enamel-formation to destruction. Robinson C, Kirkham J, Shore RC, editors. Boca Raton, FL : CRC Press, pp. 105-134.
22.
Robinson C., Brookes SJ, Kirkham J., Bonass WA, Shore RC (1996). Crystal growth in dental enamel: the role of amelogenins and albumin. Adv Dent Res10:173-180.
23.
Robinson C., Brookes SJ, Bonass WA, Shore RC, Kirkham J. (1997). Enamel maturation. In: Dental enamel. CIBA Foundation. Chichester, UK: John Wiley & Sons, pp. 156-174.
24.
Simmer JP, Fincham AG (1995). Molecular mechanisms of dental enamel formation . Crit Rev Oral Biol Med6:84-108.
25.
Simmer JP, Lau EC, Hu CC, Aoba T., Lacey M., Nelson D., et al. (1994). Isolation and characterization of a mouse amelogenin expressed in Escherichia coli. Calcif Tissue Int54:312-319.
26.
Simmer JP, Fukae M., Tanabe T., Yamakoshi Y., Uchida T., Xue J., et al. (1998). Purification, characterization and cloning of enamel matrix serine proteinase 1. JDent Res77:377-386.
27.
Zhang J., Kirkham J., Wallwork ML, Smith Dam, Brookes SJ, Shore RC, et al. (1999). The use of self-assembled monolayers as substrates for atomic force imaging of hydroxyapatite crystals from mammalian skeletal tissues. Langmuir15:8178-8183.
