Week 12 Ch 17 - Abrasion, finishing, polishing

finishing

removes excess restorative material, producing a smooth surface; done with cutting rotary instruments

polishing

produces a smooth, shiny surface using mild abrasives; produces little changes in the surface

grit

the size of the abrasive particles - coarse, medium, fine, superfine

margination

removal of excess restorative material from the margins of restorations

Mohs hardness

am measure of hardness on a scale of 1-10 where 1 is very soft material and 10 is hardest

flash

feather-like excess of material present at the margins of a restoration typically on occlusal and proximal surfaces

air abrasion

similar to air polishing but using greater air pressure and harder particles; used to cleanse cast appliances before cementation, repair porcelain and composite restorations, prepare tooth surfaces before bonding and cut tooth structure for restorative preparations

bonded abrasives

reusable point on mandrel and disposable cup, point and disk with sterilizable mandrel

carbide finishing bur

the more flutes the finer the finish; primarily used for finishing

silicon carbide

coated disks, rotary devices; used in finishing procedures

aluminum oxide

white or tan powder used for sandblasting restorations in preparation for cementation and air abrasion

sand/quartz

coated disks, handheld strips; natural not synthetic

silicon dioxide

commonly found in prophylaxis paste

pumice

volcanic silica manufactured as a loose abrasive; found in prophylaxis paste used to polish tooth structure

tin oxide

fine abrasive used to polish enamel and restorations; powder that is mixed with water

calcium carbonate

chalk or whiting; found in prophylaxis paste and dentifrice

polishing materials

should be harder (by one or 2 mohs) than the surface to which they are applied

cleaning materials

should be equal to or less hard than the surface to which they are applied