Composite Layering to create natural depth and translucency RSD 810 Spring 2016 Rodriguez D.M.D.

The restorative dentist must understand the optical properties of tooth structure as well as those of composite material. As we progress through this course we will learn to mimic with composite the natural characteristics such as hue, value, chroma, opacity, and translucency. These variations are due to the lack of uniformity in the quantity of enamel and dentin from cervical to incisal.

The color and opacity of the tooth originate from dentine, the enamel being mostly translucent and colorless. Opacity is more prominent in the cervical third because dentin is thicker while enamel is thinner in that area. Translucency is often more important in the incisal third where dentin is thin or absent and enamel is thick which may create some effects such as the perception of dentinal lobes, a high level of translucency and sometimes a halo effect at the incisal edge.

T- Transparent (achromatic enamel) E- Enamel B- Body D- Dentin Increasing opacity, decreasing translucency

absorbed reflected absorbed reflected transmitted reflected absorbed

The lingual shell is formed by placing a very thin layer (0 The lingual shell is formed by placing a very thin layer (0.5mm) of enamel shade into the PVS matrix. In the case of an incisal edge fracture the tooth is first prepared with bevel(s), then enamel is etched, dentin is primed, and both have adhesive applied and cured prior to lingual shell formation.

Once cured, the lingual shell may show nuances of the natural amber shade depending on the enamel shade chosen.

A dentin or body shade is then used to create the internal anatomical lobes. Different instruments may be used for this step.

A very small amount of low viscosity 45% filled wetting resin may be used to lubricate contouring instruments and brushes which are then utilized to seamlessly blend each new layer of composite to the previous.

A final enamel layer may now be added to cover the entire surface of the tooth. Sometimes different chromatic enamel shades are utilized to create characteristics like the incisal halo.

Achromatic enamel may be placed over the lobes to promote higher opacity and color value. Surface texture may be added.

Defining transitional line angles

Secondary anatomy may be redefined

Polishing method Polish with Green Jiffy Follow with Yellow Jiffy Follow with White Jiffy Finish with Jiffy brush at high RPM’s and a light touch.

Today in D 611: Build a tooth using all A2B from your kits. Follow the instructions as outlined to build a tooth with provided shades.

Anterior Build a Tooth Project Power Point compliments of Ultradent. Created by Dr. Jaime Morgan

Anterior Restoration

Take note of the thickness of a dentoform tooth Take note of the thickness of a dentoform tooth. This dentoform tooth is 9 mm at this point. Be sure to recreate the same tooth contour in all dimensions.

Step 1 Form root structure using Shade A4, or the darkest shade you have. Light cure for 20 seconds between increments. A4

Step 2 Form lingual wall using shade Enamel White (EW) This layer is only ~0.5mm thick. Scallop incisal edge Light cure for 20 seconds EW

Step 3 Fill in the scalloped incisal edge with shade Trans White (TW) This is less than 0.5mm thick Light cure for 10 seconds TW

Step 4 Apply dentin layer using shade A3 The dentin is thicker at the gingival 1/3 and thinner at the incisal 1/3 Scallop the incisal edge. Cure 10 seconds

Step 5 Apply facial layer of enamel using shade Enamel White EW Apply facial layer of enamel using shade Enamel White This layer should be thin at the cervical and thicker towards the incisal Light cure for 20 seconds

Step 6 & 7 Remove tooth from silicon mold and light cure the lingual root surface for 20 seconds. Use long finishing carbide bur to adjust the anatomy and remove flash from around edges of the tooth and root

Polishing method Polish with Green Jiffy Follow with Yellow Jiffy Follow with White Jiffy Finish with Jiffy brush at high RPM’s and a light touch.

Before polish After polish (Air-inhibited layer is present)