Multiple choice In a class - II cavity preparation, the axiopulpal line angle is rounded to: prevent the fracture of enamel prevent the fracture of amalgam prevent the fracture of gingival seat prevent the fracture of dentin Reveal answer Fill a bubble to check yourself B Correct answer Explanation In an amalgam restoration, all the internal line angles are rounded because the stress concentration needs to be reduced. This is one of the principles of resistance form.