In what scenario might a preliminary impression be used?

• A. For creating study models
• B. For fitting permanent crowns
• C. For making dentures
• D. For preparing fillings

Answer: (A)

A preliminary impression is primarily used for creating study models, which are essential in dental practice for diagnostic and treatment planning purposes. Study models help the dentist evaluate the patient's occlusion, alignments, and overall dental structure. They serve as a reference for planning treatments, such as orthodontics or prosthodontics.

In contrast, impressions taken for fitting permanent crowns, making dentures, or preparing fillings typically require a more precise and detailed impression—often referred to as a final or definitive impression. These latter impressions are critical for ensuring that restorations fit accurately and function properly in the oral environment. Therefore, the use of preliminary impressions is specifically aligned with the initial steps of treatment planning and not for the finalization of restorative procedures.