The purpose of this study is to evaluate the survival rate of 5 mm short implants compared to longer implants (10 mm) placed in sinus-grafted sites. Primary aim: Compare bone loss between the two groups Secondary aim: Compare surgical time and patient-reported outcomes (satisfaction and post-operative pain)

34 patients requiring an implant to replace an upper missing tooth in the premolar or 1st molar area with a bone crest height from 5 to 8 mm will be recruited for this trial. Patients will be randomized to either the test (5-mm implant) or control group (10-mm implant) using a computer-generated randomization list . 17 patients will receive a sinus lift procedure, bone graft, and 10 mm implant while the other 17 patients will receive a 5 mm short implant.