Matrices and wedges

Question 1

Matrices

Answer 1

Siqueland matrix band 
-encircling band with retainer
-e.g. proximal amalgam restorations
Tofflemire matrix band
-encircling band with retainer
Automatrix
-no retainer
-comes with band tightening and band cutting tool
Omnimatrix
-disposable plastic retainer with metal or plastic band
Mylar strip
-for class II and class IV restorations
V-ring
-newer systems
Ivory
-partial band leaving free embrasure
-useful if contact is tight

Question 2

Wedges

Answer 2

Wood - expand on moisture absorption

Luciwedge - translucent for RC restoration

Question 3

Plastic translucent crown former

Answer 3

Poke a hole before filling it up with RC

Question 4

Functions of matrix band

Answer 4

To contain restorative material when one or more wall is absent from cavity
To shape restorative material
To stop materials escaping at cavity margins during condensation
Substitute for missing walls
Recreates contact point
Restricts extrusions to prevent overhang and ledges
Provides contour of proximal surface of restoration
Forms smooth surface to inaccessible areas
–>Can be used to protect adjacent tooth