What is the major disadvantage of stone dies used for crown fabrication?

The primary disadvantage of stone dies used for crown fabrication is the inherent limitation in their strength and durability. While stone dies can accurately replicate the details of impressions, they can be brittle and prone to fractures under stress, particularly during fabrication and manipulation processes. This weakness can compromise the integrity of the die, making it challenging to create precise restorations.

In contrast to the strength issue highlighted, other options refer to different aspects. For instance, the accurate reproduction of surface details is typically a strength of stone, and the overall dimensions are often within acceptable tolerance levels. Concerns about toxic materials during trimming are relevant but don't directly relate to the structural disadvantage of the stone material itself. Thus, the focus on the strength limitation effectively encapsulates a significant drawback associated with the use of stone dies in dental crown fabrication.