Biomaterial Database

Intercusp differences in enamel prism patterns in early and late stages of human tooth development. 2000

T Zeygerson, and P Smith, and R Haydenblit

Laboratory of BioAnthropology and Ancient DNA, The Hebrew University-Hadassah, School of Dental Medicine, 91120, Jerusalem, Israel.

Enamel prism-packing patterns reflect the past history of ameloblasts, providing information about growth patterns in tooth development. Here, the area and density of enamel prisms on the cuspal surface of molar teeth were measured to examine if the onset and rate of enamel apposition differ according to stage of development and/or cusp type. Scanning electron-microscopic images were taken from the mesiobuccal and distal cusp tips of 30 mandibular first permanent molars at different stages of development recovered from archaeological sites in Israel dating to the past 10000 years. Selected enamel microstructural characters were measured for each cusp. The mean area of prisms on the mesiobuccal (MB) cusp was significantly larger than that of the distal (D) cusp at all stages of development and the differences in prism area between cusps were significant for each stage of development. Prism density was significantly smaller on the MB cusp than the D cusp at all stages of development but no significant differences were found between early and later stages in each cusp. This was interpreted as indicating that enamel formation in the MB cusp was almost complete, even in the earliest tooth germs studied, whereas in the D cusp it was less advanced. The differences between MB and D cusps are proposed to result from asynchrony of enamel formation between the different cusps of molar teeth in recent populations. The method provides a non-destructive approach to the study of growth patterns in teeth and provides baseline data for comparison with fossil teeth.

UI	MeSH Term	Description	Entries
D008855	Microscopy, Electron, Scanning	Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.	Scanning Electron Microscopy,Electron Scanning Microscopy,Electron Microscopies, Scanning,Electron Microscopy, Scanning,Electron Scanning Microscopies,Microscopies, Electron Scanning,Microscopies, Scanning Electron,Microscopy, Electron Scanning,Microscopy, Scanning Electron,Scanning Electron Microscopies,Scanning Microscopies, Electron,Scanning Microscopy, Electron
D008963	Molar	The most posterior teeth on either side of the jaw, totaling eight in the deciduous dentition (2 on each side, upper and lower), and usually 12 in the permanent dentition (three on each side, upper and lower). They are grinding teeth, having large crowns and broad chewing surfaces. (Jablonski, Dictionary of Dentistry, 1992, p821)	Molars
D010161	Paleodontology	The study of the teeth of early forms of life through fossil remains.
D012016	Reference Values	The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.	Normal Range,Normal Values,Reference Ranges,Normal Ranges,Normal Value,Range, Normal,Range, Reference,Ranges, Normal,Ranges, Reference,Reference Range,Reference Value,Value, Normal,Value, Reference,Values, Normal,Values, Reference
D003743	Dental Enamel	A hard thin translucent layer of calcified substance which envelops and protects the dentin of the crown of the tooth. It is the hardest substance in the body and is almost entirely composed of calcium salts. Under the microscope, it is composed of thin rods (enamel prisms) held together by cementing substance, and surrounded by an enamel sheath. (From Jablonski, Dictionary of Dentistry, 1992, p286)	Enamel,Enamel Cuticle,Dental Enamels,Enamel, Dental,Enamels, Dental,Cuticle, Enamel,Cuticles, Enamel,Enamel Cuticles,Enamels
D005580	Fossils	Remains, impressions, or traces of animals or plants of past geological times which have been preserved in the earth's crust.	Fossil
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000565	Ameloblasts	Cylindrical epithelial cells in the innermost layer of the ENAMEL ORGAN. Their functions include contribution to the development of the dentinoenamel junction by the deposition of a layer of the matrix, thus producing the foundation for the prisms (the structural units of the DENTAL ENAMEL), and production of the matrix for the enamel prisms and interprismatic substance. (From Jablonski's Dictionary of Dentistry, 1992)	Ameloblast
D014083	Tooth Germ	The collective tissues from which an entire tooth is formed, including the DENTAL SAC; ENAMEL ORGAN; and DENTAL PAPILLA. (From Jablonski, Dictionary of Dentistry, 1992)	Germ, Tooth,Germs, Tooth,Tooth Germs
D018709	Statistics, Nonparametric	A class of statistical methods applicable to a large set of probability distributions used to test for correlation, location, independence, etc. In most nonparametric statistical tests, the original scores or observations are replaced by another variable containing less information. An important class of nonparametric tests employs the ordinal properties of the data. Another class of tests uses information about whether an observation is above or below some fixed value such as the median, and a third class is based on the frequency of the occurrence of runs in the data. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1284; Corsini, Concise Encyclopedia of Psychology, 1987, p764-5)	Kolmogorov-Smirnov Test,Kruskal-Wallis H Statistic,Mann-Whitney U Test,Rank-Sum Tests,Spearman Rank Correlation Coefficient,Wilcox Test,Wilcoxon Rank Test,Non-Parametric Statistics,Nonparametric Statistics,Statistics, Non-Parametric,Kolmogorov Smirnov Test,Mann Whitney U Test,Non Parametric Statistics,Rank Sum Tests,Rank Test, Wilcoxon,Rank-Sum Test,Statistics, Non Parametric,Test, Kolmogorov-Smirnov,Test, Mann-Whitney U,Test, Rank-Sum,Test, Wilcox,Test, Wilcoxon Rank,Tests, Rank-Sum,U Test, Mann-Whitney