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What is Which of the following is not a modification for the class III cavity preparation to receive direct filling gold restorations? and explain in detail?
Class V with unilateral or bilateral “moustache” extensions occlusally:
Sometimes surface defects occlusal to the height of contour are continuous with a gingival third lesion, necessitating their involvement in the Class V cavity preparation and their restorations. So one or two occlusal extensions are added to the basic trapezoidal Class V cavity preparation.