A deep cleaning is not a more thorough version of a regular cleaning. It treats a different problem: deposits and inflammation below the gum line, where a routine cleaning does not reach.
Below the gum line, along the root surface, rather than mainly above it.
Why it is done
To treat measured pocket depths and inflammation, not for polish.
Comfort
Usually done with local anaesthetic, often in sections across visits.
Afterwards
Some tenderness and sensitivity for a few days is common.
Maintenance
Intervals are usually shorter afterwards, because the tissue needs monitoring.
What it can and cannot do
Deep cleaning can reduce inflammation, reduce pocket depths, and stabilise a situation that was progressing. What it cannot do is regrow bone that has already been lost. That is the honest boundary, and it is why we would rather measure early than treat late.
Some cases respond well and settle into maintenance. Others need a periodontist involved. That judgement follows re-measurement, not a promise beforehand.
What we can explain here — and what needs an exam
A page can inform you. It cannot examine you.
We can explain online
What scaling and root planing involves
Why anaesthetic is usually used
Why maintenance intervals shorten
That lost bone does not regrow
Determined after an exam
Whether you need deep cleaning at all
How many visits and which areas
Whether a periodontist should be involved
How your tissue responds on re-measurement
What to do next
A gum evaluation produces the numbers that decide this. Ask for one at your next exam.