Dental OSCE (Objective Structured Clinical Examination) Practice Exam

What type of leakage is often associated with composite failure?

1. Macroleakage

2. Microleakage

3. Subsurface leakage

4. Surface retention

The correct answer is: Microleakage

Microleakage is the phenomenon often linked with composite failure. It refers to the microscopic gaps that can occur at the interface between the composite material and the tooth structure. These gaps may allow saliva, bacteria, and other substances to penetrate, leading to post-operative sensitivity, secondary caries, or even restoration failure. Understanding microleakage is crucial because it can significantly affect the longevity and success of composite restorations. Factors such as the bonding technique, the properties of the composite material itself, and the placement technique can influence the extent of microleakage. For instance, inadequate bonding can create a space that facilitates microleakage, while proper bonding techniques can minimize this risk, thus enhancing the durability of the restoration. Macroleakage, on the other hand, refers to larger gaps or failures often associated with more significant structural issues and is less common than microleakage. Subsurface leakage typically involves penetration beneath the surface of a material, which is also less relevant to the question regarding composite failure. Surface retention refers to the ability of a material to adhere to the tooth surface, which is somewhat related but does not directly describe the phenomenon of leakage itself. Thus, the focus on microleakage captures the essential issue related to