Dental OSCE (Objective Structured Clinical Examination) Practice Exam

When are semi-precision attachments utilized?

1. When definite parallelism between abutments is attainable

2. When there is tooth mobility

3. When parallelism between abutments is not attainable with conventional clasps

4. For all removable partial dentures

The correct answer is: When parallelism between abutments is not attainable with conventional clasps

Semi-precision attachments are specifically designed for situations where achieving parallelism between abutments is not feasible, especially with conventional clasps. These attachments allow for more flexibility and can accommodate slight misalignments between the supporting teeth without compromising retention and stability. In cases where the natural teeth do not have ideal positioning, using semi-precision attachments can facilitate a better fit for removable partial dentures. This is crucial in enhancing the functionality and comfort for the patient. Additionally, semi-precision attachments can provide improved aesthetics compared to traditional clasps, as they are less visible. The other contexts presented do not adequately justify the use of semi-precision attachments. For instance, when definite parallelism between abutments is attainable, conventional clasps would suffice and be more straightforward. Similarly, tooth mobility might be a consideration for the overall design and choice of attachments, but it does not specifically necessitate the use of semi-precision attachments, which are more about the alignment of the abutments than the mobility of the teeth themselves. Lastly, while removable partial dentures may use semi-precision attachments, they are not used for all cases, as their application is more specialized.