Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

External shape of enamel crystals.

H Warshawsky1

  • 1Department of Anatomy, McGill University, Montreal, Quebec, Canada.

Scanning Microscopy
|December 1, 1987
PubMed
Summary

Biological intelligence guides hydroxyapatite crystal growth in enamel through protein templates. Models suggest rhombohedral crystal shapes, appearing hexagonal, explain the protein

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Hepatic complications of amebiasis.

The New England journal of medicine·2010
Same author

Malaria.

Minnesota medicine·2010
Same author

Diagnostic and therapeutic pointers on malaria.

Clinical medicine (Northfield, Ill.)·2010
Same author

Localization of specific binding sites for 125I-TGF-beta1 to fenestrated endothelium in bone and anastomosing capillary networks in enamel organ suggests a role for TGF-beta1 in angiogenesis.

Calcified tissue international·2001
Same author

Cell-specific expression of the parathyroid hormone (PTH)/PTH-related peptide receptor gene in kidney from kidney-specific and ubiquitous promoters.

Endocrinology·1997
Same author

Programmed cell death of chondrocytes and aberrant chondrogenesis in mice homozygous for parathyroid hormone-related peptide gene deletion.

Endocrinology·1996

Area of Science:

  • Biomineralization
  • Crystallography
  • Dental Enamel Structure

Background:

  • Biological hydroxyapatite crystals vary in size, with enamel crystallites exhibiting unique growth patterns.
  • Enamel crystallite growth in vivo is directed by protein templates, unlike in vitro physico-chemical growth.
  • The 'crystal ghost' concept, where organic templates appear within crystals, presents a logical inconsistency.

Purpose of the Study:

  • To investigate the true cross-sectional shape of enamel crystallites.
  • To reconcile the apparent presence of protein templates within enamel crystals.
  • To explore alternative crystallite shapes beyond hexagonal.

Main Methods:

  • Modeling of crystallite shapes, comparing hexagonal, rectangular, and rhombohedral rods.
  • Analysis of projected shapes of rod segments under electron microscopy conditions.
  • Evaluation of the location of organic templates relative to crystal exterior.

Main Results:

  • Enamel crystallites appear hexagonal in cross-section, but this may not be their true shape.
  • Segments of hexagonal rods would project as octagons, which are not observed.
  • Rectangular or rhombohedral rod segments project as hexagons, consistent with observed morphology.

Conclusions:

  • The hexagonal appearance of enamel crystallites likely results from the projection of rhombohedral or rectangular shapes.
  • This projection explains the apparent 'crystal ghost' by showing the exterior protein template.
  • The study resolves the inconsistency of proteins being accommodated within crystals.

Related Experiment Videos