Clinical Success of Short Dental Implants Alone and Standard Dental Implants Combined With Osteotome Sinus Floor Elevation in Posterior Maxillae

Inclusion Criteria: The following inclusion criteria are applied: * age≧18 years, partial edentulism in posterior maxilla for at least three months from tooth loss, * residual bone height range from 6-8mm, * sufficient bone width in edentulous region. Exclusion Criteria: The patients will be excluded on the basis of: * heavy smoker (\>10 cigarettes per days), * uncontrolled diabetes mellitus or other systemic diseases, * uncontrolled periodontal infection, * insufficient bone quality to achieve implant stability and * previous implant installation or bone grafting at surgical site.