ISFPR refers to one-or multiple-piece prosthesis fabricated on implants (usually placed 6–10) and joined to an abutment with cement/or screw ways. ISCFPR, on the other hand, was used to describe removable-fixed restorations known as Hybrid, which are generally made in one piece using 4–6 implants. In these prostheses, straight or angled abutments called multi-abutments are used, and the prostheses are screwed to the abutments. THP (Traditional Hybrid Prostheses) refers to one-piece screw-retained prostheses supported by axial implants, whereas 4/6 NHP (New-type Hybrid Prostheses) refers to one-piece screw-retained prostheses supported by straight and angled implants according to the ‘All-on-Four/Six’ concept. The number of implants used in this type of prosthesis is usually between 4 and 6.