OPTION 1

DENTAL SAC

 

•            The dental sac exhibits a circular arrangement of fibres and resembles a capsule around the enamel organ.

•            The fibres of the dental sac form the periodontal ligament fibers that span between the root and the bone.

•            The junction between the inner enamel epithelium and odontoblasts outlines the future of dentino-enamel junction.

 

Early bell stage of tooth development

 

•            The cells of the outer enamel epithelium flatten to a low cuboidal form. At the end of the bell stage, preparatory to and during the formation of enamel, the formerly smooth surface of the outer enamel epithelium is laid in folds.

•            Between the folds the adjacent mesenchyme of the dental sac forms papillae that contain capillary loops and thus provide a rich nutritional supply for the intense metabolic activity of the avascular enamel organ.

•            This would adequately compensate the loss of nutritional supply from dental papilla owing to the formation of mineralized dentin.

 

Key concept

 

Vascular and Nerve Supply during Tooth Development

Vascular Supply:

•            Clusters of blood vessels in dental follicle and papilla.

•            Clustering of vessels in papilla coincide with position of root formation.

•            Enamel organ is avascular, however vessels seen in close association in the follicle.

 

Nerve Supply:

•            Initially noted in the dental follicle during bud to cap stage.

•            However after start of dentinogenesis, seen in dental papilla.

•            Nerve fibers do not enter enamel organ.