A.刷頭較小 B.毛束間距適當(dāng) C.刷毛軟且頂端圓鈍 D.刷毛長度適當(dāng) E.刷毛毛束排列成V形
A.面牙尖斜度約40° B.面牙尖斜度約35° C.面牙尖斜度約30° D.面牙尖斜度約25° E.面牙尖斜度約20°
A.30° B.45° C.60° D.90° E.135°