Physiologic Process of Deciduous Teeth

Nolla’s Stage

Timeline of crown and root formation.

Leeway

Presence of excessive ______ space provides for mesial movement of permanent molars.

Leeway Space

Is utilized for the mesial drift of the mandibular molars to establish Class I molar relation.

1.8 mm

Maxillary arch, what mm in leeway stage?

3.4 mm

Mandibular arch, what mm in leeway stage?

Primate Spaces

Maxilla; between lateral incisor and canine.

Primate Spaces

Mandibular; between canine and first molar.

Interdental Spaces

Generalized spacing between incisors and anterior teeth in the primary dentition.

Physiological Root Resorption

Of deciduous teeth; a complex physiological process essential for normal replacement of deciduous teeth and permannet teeth.

Odontoclasts

Recruited when cementoblasts and protective precementum layers are damaged during exfoliation or shredding of deciduous root or due to trauma, pressure, or inflammation.

Odontoclasts

Signals such as cytokines, RANKL, and inflammatory mediators stimulate their differentiation.

Cytokines

Signaling protein, facilitate bone PDL differentiation, activation and apoptosis.

Chemokines

Small proteins that induce cells migrations.

Growth Factors

Stimulates cell proliferation, migration, and differentiation.

Prostaglandin

Stimulates osteoclastic process of bone resorption.

Incisors → Canines → Molars

Sequence of root resorption (teeth).

Mixed Dentition Stage

Overlap of primary and permanent teeth. Important in orthodontic diagnosis.

Physiologic Spacing

Primate spaces (mesial to upper canines, distal to lower canines). Interdental spacing for alignment of larger permanent teeth.

Leeway Space

Difference in mesiodistal width between primary molars and permanent premolars. Significant in arch length preservation and occlusion development.