Siloing a Wordpress Site - Posts vs Pages

Does it matter if I use posts vs pages to silo my wordpress site?

Right now I am setting it up so I have something like...

Pacific NorthWest Dentists (home PAGE)
-Resources for Clients (PAGE and CATEGORY)
--Dentistry Anesthesia (PAGE and CATEGORY)
---what to expect from anesthesia (POST)
---different kids of anesthesia (POST)
---how long does anesthesia last for (POST)
--Office Locations (PAGE and CATEGORY)
---seattle dentist (POST)
---portland dentist (POST)

and so on. each page is named the same as the category, and SEOUltimate is set to default to the PAGE when page and category are the same name. so i create a page like Office Locations and then have some text about Office Locations, and then a short code plugin in that page to list all the posts within that category.

the problem is i can't find a plugin that lets me properly nest all the posts and i'm getting totally confused.

first, the siloing feature of the seoultimate plugin lists ALL posts within the office locations and dentistry anesthesia category if i use it on the resources for clients page. the widget shortcodes seem to do the same thing too.

all i want is the subcategories and not the posts that are one extra category deeper.

seems like a clean way to do this is just to have my POSTS be PAGES instead, since i a setting up a static site and that's really content management and not a blog.

but i keep reading that siloing a site should be done with posts. so i'm confused.

anyone have any advice?