Shedding of Deciduous Teeth

Shedding of Teeth

• Shedding or exfoliation is the normal physiological process of eliminating deciduous teeth.
• The loss of deciduous teeth is mainly due to the resorption of their roots.

Need of Shedding

• With the growth of a child, the jaw grows, but the deciduous teeth cannot.
• The muscle of mastication increases in size and power of contraction.
• The PDL of deciduous teeth cannot withstand the masticatory forces.

Rules of "Sixes" in Dental Development

• 6 weeks old in utero: beginning of dental development
• 6 months old: emergence of the first primary tooth
• 6 years old: emergence of the first permanent tooth

Mechanism of Shedding

• Pressure of the succeeding permanent teeth
• Increase in force of mastication
• Action of odontoclast (cementoclast for cementum and dentinoclast for dentin)
• Action of osteoclast, which resorbs bone
• PDL is resorbed by fibroclast

Pattern of Shedding

Anterior Teeth

• Resorption of deciduous teeth starts from the lingual side
• Later developing tooth occupies a position directly apical to deciduous teeth

Posterior Teeth

• Resorption of deciduous teeth begins on the inner surface of the roots of molar
• Resorption occurs long before the deciduous molars are shed

Process of Shedding

• First step: pressure from successional teeth
• Leads to activation of osteoclast, odontoclast, and fibroclast

Osteoclasts

• Bone-resorbing cells derived from the monocyte-macrophage lineage
• Giant multinuclear cells with 4-20 nuclei
• Resorb hard tissue by separating mineral from the collagen matrix through the action of hydrolytic enzymes
• Resorption occurs at the ruffled border, which greatly increases the surface area of the osteoclast in contact with bone

Odontoclasts

• Origin: circulating monocytes
• Function: resorption of all dental hard tissue, including enamel

Fibroclast/Fibroblast

• PDL is resorbed by fibroclast
• Resorbs collagen fibers

Clinical Considerations

• Remnants of the root of deciduous teeth
• Retained/submerged deciduous teeth
• Pathological resorption

Learn about the normal physiological process of shedding or exfoliation of deciduous teeth, its causes and effects, and the need for shedding in children.