TYPE OF PINS Cemented Friction – locked pins Self-threading pin (TMS)
Cemented pin Larger than other pin. Use Zn Ph cement or Zn Polycarp cement.
Friction – locked pins Smaller. Retained by resilience of dentin ↑ retentive than cemented pin. With ttme denttiin relax -> loose pin.
Self-threading pin (TMS) Different size Threads engage dentin Depend on elasticity of dentin Most retentive (3-6 times) No corrosion (gold plated) Create horizontal & vertical stress Cause dentinal craze line (size of pin)
Pin Thread mate system Regular 0.031 inch diameter Minim 0.024 inch diameter Minikin 0.019 inch diameter Minuta 0.017 inch diameter
Pin Thread mate system Available in: Double shear (two pins in one) Gold plated, stainless steel or titanium alloy Inserted manually or with low speed, latch-type hand piece
Thank you Reference : Art and science of operative dentistry 2000chapter ……. 19pages ………. 771 -772