Which of the following blade angle is appropriate for scaling and root planing
(A) A (B) B (C) C (D) D
(B) Blade angulation.
(A) 0 degrees: correct angulation for blade insertion.
(B) 45 to 90 degrees: correct angulation for scaling and root planing.
(C) less than 45 degrees: incorrect angulation for scaling and root planing.
(d) More than 90 degrees: incorrect angulation for scaling and root planing, but correct angulation for gingival curettage.