Advantages of abutment-supported prostheses are 1) When implants are not parallel to each other, the use of angulated abutments can "correct" for the non-parallelism 2) Angulated abutments are available for a screw-retained prosthesis and 3) Custom abutments can be...

In the edentulous upper jaw implant insertion can be limited due to the adjacent anatomical structures (nasal floor, maxillary sinus). Less than 5-6 mm in height and 6 mm in width requires augmentation before implant placement....