5. CEJ relationships / 6. Cementum composition

C. Cementogenesis

5. CEJ RELATIONSHIPS / 6. CEMENTUM COMPOSITION

 

5. Relationships of cementum to the apical enamel border

The relationship of the cementum to the apical enamel border is variable.   Fig. 103 illustrates diagramatically the various possibilities that exist.
histo118a2_sm.jpg (4145 bytes)
Fig. 103 (From unknown source):  A, the cementum (C) and the enamel (E) can form a butt joint.  B, the cementum and the enamel may be separated by a gap with exposed dentin.  C, the cementum on the root may be continuous with a patch of coronal cementum, so that the cementum overlaps the enamel.  These relationships may co-exist on a single tooth.  The relationship in C has been reported to be the most common of the three.


6. Comparative composition of the major mineralized tissues

Cementum is the least mineralized of the 3 calcified dental tissues, but is more mineralized than bone, as shown in the following table. 





(From Schroeder, H.E.,1991)


  % by weight                
  Enamel                  
  Dentin
  Cementum
  Bone




  Mineral
    95
    70
    61
    45



  Organic  1  20  27  30


  Water  4  10  12  25







  

    University of
    Pennsylvania

    University of Pennsylvania and Temple
    University © 1999. All rights reserved.

    Created: May 8, 1999  Revised: 

    URL: 

    Max A. Listgarten: Comments to author: max@listgarten.com

    (Technical Support: TU Department of Dental Informatics: Heiko Spallek) 		
    Temple University