PULPO-DENTINAL COMPLEX

PULPO-DENTINAL COMPLEX

1. SPECIALISED CONNECTIVE TISSUE

   • 70%mineral(HA) 20%organic matrix(collagen)
     • Collagen fibres run parallel to ADJ: gives Dentine strength
       • PRE-DENTINE is found near pulp+non mineralised

2. DENTINE is highly tubular

   • May contain cell process, nerves, fluid that flows out due to Pulp pressure
     • Makes dentine a VITAL Tissue

3. DENTINE FORMATION

   • Mineralised produced by odontoblasts
     • Retreat inwards from ADJ
     • Organic matrix(predentine) that sis then mineralised to dentine
     • Long odontoblast processes that retreat due to dentinal tubules

4. NERVES IN DENTINE

   • Sparsely innervated
     • most located at predentine near pulp horns

5. CLASSIFICATIONS OF DENTINE

   • MANTLE:laid down first at ADJ
     • CIRCUMPULPAL:rest of dentine, parallel to ADJ
       • PRIMARY:formed during tooth development
         • SECONDARY:formed after root completion
           • TERTIARY:response to pulpal irritation
           • 2 types:Reactionary uses existing Odontoblasts
             • Reparative:recruits new odontoblasts
         • PERI TUBULAR:around tubules
           • INTRA TUBULAR: between tubules

6. INCREMENTAL LINES OF VON EBNER

   • positions of odontoblasts during development

7. DEFENCE RESPONSES OF DENTINE

   • SCLEROIS: tubules become blocked with pertubular dentine
     • found under low grade stimulis (protective)
       • Tertiary Dentine