When I visit dental offices I see a range of sizes for treatment rooms.
Generally they range from large to absolutely enormous. It's such a waste in 2 ways.
The first way is because space costs money. The second way is because large treatment rooms almost force you to work inefficiently.
Whenever I see large treatment rooms I see banks of drawers and benches covering the available walls. In the drawers are a hodge podge of badly arranged instrument and materials most of which never see the light of day. To find anything is a hassle and often requires you to get up and walk across the room.
There seems to be an immutable law that materials and equipment expand to fill all the available space. When you don't have much space you have to carefully think through what you do and simplify.
The treatment rooms in my office were 2.2m x 3.5m and gave me plenty of space to do any treatment. The total bench space was less than 1 meter square and we seldom used more than 1/2 of it.
If you'd like to find out how to make small treatment rooms work for you then please let me know.