74. Ooe T. Human tooth and dental arch development. Tokyo: Ishiyaku, 1981.
75. Harada H, Kettunen P, Jung H-S, Mustonen T, Wang YA, Thesleff I. Localization of putative stem cells in dental epithelium and their association with Notch and FGF signaling. J Cell Biol 1999;147:105–120.
76. Mitsiadis TA, Henrique D, Thesleff I, Lendahl U. Mouse serrate-1 (jagged-1): Expression in the developing tooth is regulated by epithelial-mesenchymal interactions and fibroblast growth factor-4. Development 1997;124:1473–1483.
77. Bretscher MS. Getting membrane flow and the cytoskeleton to cooperate in moving cells. Cell 1996;87:601–606.
78. Mitchison TJ, Cramer LP. Actin-based cell motility and cell locomotion. Cell 1996;84:371–379.
79. Haemmerli G. Principles of cell motility and their morphologic manifestations. Exp Biol Med 1985;10:89–117.
80. Abercrombie M, Heaysman JEM, Pegrum SM. The locomotion of fibroblasts in culture. IV. Electron microscopy of the leading lamella. Exp Cell Res 1971;67:359–367.
81. Couchman JR, Rees DA. The behavior of fibroblasts migrating from chick heart explants: Changes in adhesion, locomotion and growth, and in the distribution of actomyosin and fibronectin. J Cell Sci 2002;39:149–165.
82. Izzard CS, Izzard SL, DePasquale JA. Molecular basis of cell-substrate adhesions. Exp Biol Med 1985;10:1–22.
83. Turner CE, Burridge K. Transmembrane molecular assemblies in cell-extracellular matrix interactions. Curr Opin Cell Biol 1991;3:849–853.
84. Brown MJ, Loew LM. Graded fibronectin receptor aggregation in migrating cells. Cell Motil Cytoskeleton 1996;34: 185–193.
85. Duband JL, Nuckolls GH, Ishihara A, Hasegawa T, Yamada KM, Thiery JP, Jacobson K. Fibronectin receptor exhibits high lateral mobility in embryonic locomoting cells but is immobile in focal contacts and fibrillar streaks in stationary cells. J Cell Biol 1988;107:1385–1396.
86. Couchman JR, Blencowe S. Adhesion and cell surface relationships during fibroblast and epithelial migration in vitro. Exp Biol Med 1985;10:23–38.
87. Schor SL, Ellis I, Dolman C, Banyard J, Humphries MJ, Mosher DF, Grey AM, Mould AP, Sottile J, Schor AM. Substratum-dependent stimulation of fibroblast migration by the gelatin-binding domain of fibronectin. J Cell Sci 1996;109: 2581–2590.
88. Hay ED. Interaction of migrating embryonic cells with extracellular matrix. Exp Biol Med 1985;10:174–193.
89. Bernanke DH, Markwald RR. Migratory behavior of cardiac cushion tissue cells in a collagen-lattice culture system. Dev Biol 1982;91:235–245.
90. Harris AK, Stopack D, Wild P. Fibroblast traction as a mechanism for collagen morphogenesis. Nature 1981;290:249–251.
91. Arnaout MA. Cell adhesion molecules. In: Kelley WN, Harris ED, Ruddy S, Sledge CB (eds). Textbook of Rheumatology, ed 4. Philadelphia: Saunders, 1993:213–226.
92. Obara N, Takeda M. Expression of the neural cell adhesion molecule (NCAM) during second- and third-molar development in the mouse. Anat Embryol 1993;188:13–20.
93. Gumbiner BM. Cell adhesion: The molecular basis of tissue architecture and morphogenesis. Cell 1996;84:345–357.
94. Hynes RO. Integrins: Versatility, modulation, and signalling in cell adhesion. Cell 1992;69:11–25.
95. Salmivirta K, Gullberg D, Hirsch E, Altruda F, Ekblom P. Integrin subunit expression associated with epithelial-mesenchymal interactions during murine tooth development. Dev Dyn 1996;205:104–113.
96. Bai XM, Van der Schueren B, Cassiman J-J, Van den Berghe H, David G. Differential expression of multiple cell-surface heparan sulfate proteoglycans during embryonic tooth development. J Histochem Cytochem 1994;42:1043–1054.
97. Hynes RO, Yamada KM. Fibronectins: Multifunctional modular glycoproteins. J Cell Biol 1982;95:369–377.
98. Yamada KM, Hayashi M, Hirano H, Akiyama SK. Fibronectin and cell surface interactions. In: Trelstad RL (ed). The Role of Extracellular Matrix in Development. New York: Liss, 1984: 89–121.
99. Garbarsch C, Matthiessen ME, Olsen BE, Moe D, Kirkeby S. Immunohistochemistry of the intercellular matrix components and the epithelio-mesenchymal junction of the human tooth germ. Histochem J 1994;26:110–118.
100. Nagai N, Yamachika E, Nishijima K, Inoue M, Shin HI, Suh MS, Nagatsuka H. Immunohistochemical demonstration of tenascin and fibronectin in odontogenic tumours and human fetal tooth germs. Eur J Cancer B Oral Oncol 1994;30B: 191–195.
101. Sawada T. Expression of basement membrane components in the dental papilla mesenchyme of monkey tooth germs— An immunohistochemical study. Connect Tissue Res 1995; 32:55–61.
102. Timpl R, Brown JC. The laminins. Matrix Biol 1994;14: 275–281.
103. Salmivirta K, Sorokin LM, Ekblom P. Differential expression of laminin α chains during murine tooth development. Dev Dyn 1997;210:206–215.
104. Yoshiba K, Yoshiba N, Aberdam D, Meneguzzi G, Perrin-Schmitt F, Stoetzel C, et al. Expression and localization of laminin-5 subunits during mouse tooth development. Dev Dyn 1998;211:164–176.
105. Tucker RP, Moiseiwitsch JRD, Lauder JM. In situ localization of tenascin mRNA in developing mouse teeth. Arch Oral Biol 1993;38:1025–1029.
106. Paulsson M. Basement membrane proteins: Structure, assembly, and cellular interactions. Crit Rev Biochem Mol Biol 1992;27:93–127.
107. Timpl R, Dziadek M, Fujiwara S, Nowack H, Wick G. Nidogen: A new, self-aggregating basement membrane protein. Eur J Biochem 1983;137:455–465.
108. Dziadek M. Role of laminin-nidogen complexes in basement membrane formation during embryonic development. Experientia 1995;51:901–913.
109. Meyer J-M, Ruch JV, Kubler MD, Kupferle C, Lesot H. Cultured incisors display major modifications in basal lamina deposition without further effect on odontoblast differentiation. Cell Tissue Res 1995;279:135–147.
110. Kitamura H. Embryology of the Mouth and Related Structures. Tokyo: Maruzen, 1989:12–34.
Dentin is deposited by odontoblasts that develop ectomesenchymal cells of the dental papilla on contact with the basal lamina formed by the inner enamel epithelium.
Differentiation of Odontoblasts
Odontoblast precursors migrate into the developing jaw from the neural crest as part of a large population of ectomesenchymal cells that participate in the formation of many parts of the face and oral cavity. During the cap stage of tooth formation, the preodontoblasts concentrate adjacent to the inner enamel epithelium (IEE) of the enamel organ. Preodontoblasts exit the cell cycle and differentiate before the preameloblasts of the IEE have stopped dividing.1,2
Contact with the IEE basement membrane and/or with other associated extracellular material of epithelial origin has long been held to be a requirement for initial odontoblastic differentiation.3 Recent experiments suggest that a fibronectin-rich substratum is a key requirement.4 Early studies implicating the importance of the basement membrane in odontoblast differentiation were reviewed by Ruch1,2 and Ruch et al.5
Aperiodic fibrils are key structures regulating the differentiation of odontoblasts. They are deposited first at the tip of the future