Permanent Bridge: Fixed in place and attached to adjacent teeth or implants. It stays in your mouth permanently.
Semi-Permanent Bridge: Also fixed but may be easier to adjust or replace if needed. It remains in place but can be removed by a dentist.
Partial Denture: Removable and includes a pink gum-like base with replacement teeth. It can be taken out for cleaning.
In essence, bridges are fixed and non-removable, while partial dentures are removable and have a gum-coloured base.