Is there such thing as a upper wisdom erupted normally is too hard to do filling because of its position being the last?

If maxillary wisdoms are extracted, will it correct an overjet problem without orthodontics? will all the maxillary teeth slowly drift backwards to fill the space where the wisdoms were?

Government dentists practises both amalgam and composite filling?
Was told by the clerk that if molar they will use amalgam and front teeth they use composite, not sure how valid or knowledgeable she is.
So does government dentists decide amalgam or composite based on tooth position?
Can patients decide what they want?

2nd. Do all government dentists use ultrasonic scalars? Or they use manual tools to dig out tartar?

Are toothbrush with thin bristles better? Nowadays the marketing gimmick goes like 0.01mm or 0.02mm, it used to be Systema doing commercial boasting about thin bristles then others started following. Now there are even those black coloured bristles and they call it charcoal. What's the professional opinions?

I have unbalanced lower incisors, meaning 1 or 2 incisor is slightly behind the other incisors, like roof tiles overlapping a bit to the next tile. A toothbrush is too broad to properly brush the surface that is stacked behind another incisor. Thus incisors become stained and too eager brushing of the submerged incisor causes more abrasion to the incisor on front.Any solutions?