Under which conditions should an agenic tooth be left open rather than closed?

Leaving an agenic tooth open is often indicated when the dental arches are well-aligned. When the dental arches are in harmony and properly spaced, closing the space left by an agenic tooth could lead to undesirable tooth movement, crowding, or misalignment of the adjacent teeth. By keeping the space open, it allows for the potential for better eruption and alignment of future teeth, as well as maintaining the natural arch form.

In contrast, high caries risk in adjacent teeth might suggest a need for monitoring or treatment rather than leaving the space open. Severe probing depth is typically a sign of periodontal issues, which would usually necessitate some form of closure or treatment rather than leaving the area exposed to further complication. Knowledge of significant crowding indicates that space may be needed elsewhere or that orthodontic treatment is required, which further supports the rationale of closing, rather than leaving an agenic tooth space open.