How can I make it so I just see the Dental Codes?

There are several ways.  The easiest is to select the "Codes" menu at the top left of your page; under "Procedures & Drugs" find "CDT Codes - Dental 'D' Codes" and select.  You will see 3 columns, in the left one the top link says "CDT Dental Codes - 'D' Codes" and the whole set will appear.

You can also use the "Search" box to search just on the CDT code set, select "HCPCS Codes" to see all HCPCS codes, and/or use any of the other Dental code related information and tools shown on the page.

The direct link is http://www.findacode.com/dental-codes/dental-codes-ada-cdt.html