48. Cleaning and polishing of metal, plastic and combined restorations.

whats in it

• why is it important

• what is its goal

• finishing, polishing and cleaning process

• points to consider

importnat because/clincially relevant because

• improves aesthetics, improves tissue health, and increases the longevity of the restorative material

goal:

• to remove excess material

• smooth roughened durfaces

• produce aesthetically pleasing appearance with minimal trauma to hard and soft tissues

process if F,P,C

Contouring

• First step: removes excess material using rotary instruments.

• Purpose: shape the restoration to correct anatomic form.

---

Finishing

• Refines and smooths the contoured surface using abrasives.

• Establishes the final shape and detail of the restoration.

---

Polishing

• Uses very fine abrasives to create a smooth, glossy surface.

• Improves appearance, soft tissue compatibility, and reduces biofilm accumulation.

• Causes minimal material removal but may need repeating over time due to staining or tarnish.

---

Material Considerations

• Polishing abrasives should be 1–2 Mohs units harder than the surface being polished.

• Scratch depth and material removal depend on abrasive particle size, shape, and hardness.

---

Diamond Abrasives

• Most abrasive material used in dentistry.

• Suitable for contouring, finishing, and polishing depending on grit size.

• Effective for both tooth structure and restorative material.

points to consider

• Number of Particles That Contact the Surface: The more concentrated the particles

  that contact the surface, the more quickly the surface will be abraded.

• -  Speed and Pressure: Increasing the speed and pressure at which an abrasive is

  applied will increase the rate of abrasion.

• -  Mode of Delivery of Abrasives: Dental abrasives are supplied in several forms:

  ▪ Two-body abrasives, including: bonded abrasives and coated abrasives (BC) before christ

  ▪ Three-body abrasives, including: Paste abrasives, loose abrasives. (PL) - post life

• Materials Used in Abrasion:

0. o Diamond

   o Tungsten Carbide Finishing Burs
   o Silicon Carbide
   o Aluminum Oxide (Corundum), Emery o Sand
   o Silicon Dioxide
   o Rouge

o Pumice
o Tin Oxide
o Calcium Carbonate
o Sodium Bicarbonate
o Potassium and Sodium