HESI General Chairside Assisting Practice Exam

During the placement of a composite restoration, which step creates a surface that is microscopically porous?

1. Etching

2. Conditioning

3. Polishing

4. Drying

The correct answer is: Conditioning

The correct answer focuses on the conditioning step when placing a composite restoration. During conditioning, a bonding agent or a primer is applied to the etched tooth surface to enhance the bond strength between the composite material and the tooth structure. This process introduces specific chemical agents that create a surface that is microscopically porous, improving the adhesion of the composite material. The porous surface generated by conditioning allows for better infiltration of the bonding agents into the tooth structure, thus facilitating a stronger bond and ultimately enhancing the longevity and success of the restorative procedure. This characteristic of porosity is crucial as it increases the effective surface area for the bonding materials to adhere. Etching also plays a vital role in preparing the tooth surface by creating a roughened texture, but it primarily removes the smear layer and opens the tubules rather than making the surface porous for bonding agents. Polishing is concerned with finishing the restoration and achieving a smooth surface, while drying is about removing moisture rather than altering the surface structure for bonding.