1Course Director: Dr. Craig Phair

perdi001@umn.edu

Dr. Jorge Perdigo

Buonocore, 1955

1955Enamel etched with phosphoric acid

Early 90s multi-step adhesivesDentin/enamel etched with phosphoric acid; n coats of primer

followed by bonding resin applied on enamel and dentin

2005No etch, no primer, no bonding

All-in-one adhesives

Mid 90s one-bottle adhesivesDentin/enamel etched with phosphoric acid; mixture of primer

and bonding resin applied on enamel and dentin+

Evolution

Composition? Resin matrix Inorganic filler Coupling agent (silane) to bond filler to resin Pigments Initiators of polymerization (light initiation or chemical initiation)

Why do composite resins shrink during polymerization?

2 Direct restorations Anterior restorations Posterior restorations

Indirect restorations Resin cements Core build-up materials..

Hybrids (Filtek Z250, Esthet.X)

(at the UofM Undergraduate Clinic)

Filtek Z250 is available in one opacity only (body)

Filtek Supreme Plus (nanofilled) and 4 Seasons (hybrid) are available in enamel and dentin opacities/shades

These composites are indicated for esthetic dentistry in clinical cases in which shade layering is required.

Enamel, body, and dentin shades

Natural teeth emit a blue fluorescence which makes them whiter and brighter in daylight

Fluorescence in Dentistry is defined as absorption of UV light by a substance and the spontaneous emission of visible light in the blue spectrum.

The most important characteristic of fluorescence is the "internal luminescence", which contributes to the vital aspect of the natural tooth

Shade matching with nanofilled composites may be more difficult than with other composites due to their low fluorescence (Lee et al., 2005)

Duarte, Perdigo, Lopes, 2004

bodybody

incisal

Take tooth shade with a Vita shade guide

cervical

Direct Composite Restoration

Bevel enamel cavo-surface angle Acid-etch for 15 sec, rinse, gently dry Apply Adper Single Bond Plus adhesive for 15 sec Gently air dry to evaporate solvent Light-cure for 20 sec Insert and sculpt composite resin Light cure in increments if thickness > 2mm Finish, check occlusion

3- Matrix band (Mylar strip )

- Free-hand (no band)

- Custom-made matrix

Matrix Systems for Anterior Composite Restorations

Clinical Use

According to the NNI (www.nano.gov) "nanotechnology" involves all of the following:

1. Research and technology development at the atomic, molecular or macromolecular levels, in the length scale of approximately 1 - 100 nanometer range.

2. Creating and using structures, devices and systems that have novel properties and functions because of their small and/or intermediate size.

3. Ability to control or manipulate on the atomic scale.