Dentin

Topics

Formation of New Dentin

Pain and pulp-dentin complex

Clinical Consideration

Formation of New DentinTypes of Dentin

Primary Secondary Tertiary

Reactionary

Reparative

Secondary Dentin• Cause: Aging• Develops after Root

Formation is completed.• On entire pulpal surface• The deposition is continuous

with primary but:i)slowerii)Fewer tubulesiii)Tubules change direction to a more wavy course

• In multi-rooted teeth, it’s thicker on the roof and floor of pulp chamber

Tertiary Dentin • Forms at a localized area in reaction

to a stimulus• Dentinal tubules less in number and

irregular arrangement• There are 2 types of Tertiary Dentine

Types of Tertiary DentinReactionary

Pre-existing odontoblast

Reparative

Newly differentiated ectomesnchymal cells

Reactionary

Reparative

Reactionary

Reparative

Reactionary dentin

Types of Reparative dentine

Topics

Formation of New Dentin

Pain and pulp-dentin complex

Clinical Consideration

Innervation of Dentin

• Subodontoplastic plexus of Raschkow

• The nerve will loose its mylien sheath then pass between the odontoblasts bodies and enter the dentinal tubules

Topics

Formation of New Dentin

Pain and pulp-dentin complex

Clinical Consideration

Clinical considerations

1. Permeability of dentin2. Response to external stimuli3. Adhesion of dental materials to dentin4. Endodontics5. Sensitivity6. Forensic Dentistry

Permeability of DentinDepends on:

Dentin surface(exposed by)

Caries

Attrition

Abrasion

trauma

Tubules(patent or occluded)

Exogenous material

Intertubular dentin

Tertiary Dentin

Adhesion of Dental materials to dentin

Endodontics• With age, secondary

and tertiary dentin are formed causing obliteration to the pulp chamber and root canal

• Treatment and prognosis in older patients is less effective

Sensitivity

• Reduction of sensitivity by occluding patent dentinal tubules by precipitation of crystalline oxalates

Forensic Dentistry• Dry teeth of

unknown dead body contain mitochondrial DNA of the interatubular nerve which are protected within the tubules could help in identification of the dead body.

Topics

Formation of New Dentin

Pain and pulp-dentin complex

Clinical Consideration

• Made by: Reem Hussam (83) Section 2