A tooth is fractured 1mm below the height of the alveolar crest. What is the minimum amount of extrusion that should be accomplished?

The situation described involves a tooth fracture occurring 1mm below the height of the alveolar crest. In order to ensure proper treatment and restoration of the tooth, it is essential to extrude the tooth enough to allow for adequate crown structure to be available for placement of a restoration.

Extrusion in this context refers to the vertical repositioning of the tooth to bring the fracture line above the alveolar crest. Since the tooth is fractured below the crest, extruding the tooth by only 1mm would simply level the fracture line with the crest and would not provide sufficient height to restore the tooth effectively. The additional extrusion is necessary to ensure that the fracture is adequately above the crest to allow for a stable and functional crown margin during the restoration process.

Moreover, a general guideline is that a minimum of 3mm to 4mm of tooth structure above the alveolar crest is usually adequate to accommodate a well-designed crown restoration. This additional extrusion helps account for potential variations in the final restoration, allows for adequate retention of restorative materials, and ensures that periodontal health is maintained around the tooth.

Therefore, the minimum amount of extrusion required in this scenario should be 4mm, which facilitates adequate restorative preparation and long-term tooth stability while considering the biological width associated