Composite Finishing

The natural tooth is rich in small details that make all the difference in integrating the restoration when they are replicated. These details include:

PRIMARY ANATOMY:

length
width
proportion length / width
buccal contour (cervical, medium and incisal)
angle lines
palatal concavity
cingulum convexity
incisal edge thickness
point and contact surface
incisal angle
embrasures

SECONDARY ANATOMY:

flat area
lobes
crests
vertical grooves
wear facets

TERTIARY ANATOMY:

texture
perikymata
fracture lines

PRIMARY ANATOMY

The primary anatomy is the main factor of the shape. It is mostly influenced by the highly-reflective lines that divide the buccal reflective surface, which is mostly flat, and the shadow area at the sides that round into the proximal areas.

Usually the main shapes that can be found, from left to right: triangular, oval and rectangular.

SECONDARY ANATOMY

The secondary anatomy is concerned with the vertical and horizontal macrotexture.

The vertical macrotexture is usually more obvious with the V-shaped grooves. They are more opened in the incisal and going more narrow to the cervical.

The horizontal macrotexture is characterized by horizontal grooves usually located in the cervical and middle third of a tooth.

TERTIARY ANATOMY

The tertiary anatomy is associated with the thin horizontal microtexture, usually called perikymata. These are usually more visible on the cervical/medium third or in the deepest part of the V-shaped grooves.

As we get older we lose secondary and tertiary anatomy

Measure and confirm the dimensions of the anterior teeth. Use calipers if necessary.
Observe the patient’s anterior teeth from various angles to ascertain the shape and surface texture.
When direct observation is not enough or becomes complicated, use auxiliary methods of texture identification, such as silver powder or articulating paper, passing over the vestibular surface of the natural tooth.

DEFINE PRIMARY ANATOMY:

Define the angle lines with a pencil
Correct the buccal contour on the three inclination planes – cervical, medium and incisal
Abrasive Discs with Mandrel
Different grains (normally 4). The lower the grain, the more polished the surface.
Use all the discs, DON'T SKIP
Use GENTLE light brushing strokes
We can use optical illusions to make the teeth look wider/narrower. To make the tooth appear narrower, move the angle lines closer together, decreasing the flat area. On the other hand to make the tooth appear wider, we should move the angle lines apart, increasing the flat area.
Embrasures - usually the distal angle is more rounded than the mesial angle
Use interproximal abrasive strips between the teeth
Cervical excess can be removed with a #12 surgical blade

2. DEFINE SECONDARY ANATOMY:

Related to the vertical macro texture and more visible with the V-shape grooves
Define the secondary anatomy vertical grooves with a pencil
Burs used with GENTLE PRESSURE and LOW SPEED

3. DEFINE TERTIARY ANATOMY & POLISH:

To create the tertiary anatomy (perikymata) use a thin low grain bur or green stone in a horizontal movement at slow speed, creating some thin lines in the composite surface.
To soften the composite resin surface and create a glossy surface, some rubber or spiral discs can be used. Usually 2 grains. Use BOTH.
Polishing paste with a felt disc.