ABSTRACT: BACKGROUND AND OBJECTIVES:Oral health-related quality of life (OHRQOL) is compromised during the post-implant healing period, especially when vertical augmentation is required. A long-term trial sought to evaluate a short dental implant system with an apically expandable macro-design. MATERIALS AND METHODS:Over 4.5 years, patients with limited vertical alveolar bone were consecutively recruited into this prospective cohort study. Implant success rate, OHRQOL (Oral Health Impact Profile (OHIP)-14), implant stability, and crestal bone changes were evaluated. RESULTS:Data from 30 patients (mean age: 64.6 years, range 44-83) were analyzed, which related to 104 implants (53 in the maxilla, 51 in the mandible). Over the mean follow-up (42.6 ± 16.4 months), the implant success rate was 94.7% in the mandible (two implants lost) and 83.6% in the maxilla (four implants lost; p = 0.096), and the prosthetic success rate was 100%. The median OHIP-14 scores improved from 23 (interquartile range (IQR) 9-25.5) to 2 (IQR 0-5; p < 0.001). The mean implant stability quotient (ISQ) was 71.2 ± 10.6 for primary stability and 73.7 ± 13.3 (p = 0.213) for secondary stability, without significant maxilla-versus-mandible differences (p ? 0.066). Compared to the baseline, median crestal bone changes after loading were 1.0 mm (IQR 0-1.3) and 1.0 mm (IQR 0.2-1.2) in the maxilla and mandible (p = 0.508), respectively, at the end of the first year, 1.1 mm (IQR 0-1.3) and 1.0 mm (IQR 0.1-1.2) (p = 0.382), respectively, at the end of the second year, and 1.2 mm (IQR 0-1.9) and 1.1 mm (IQR 0.1-1.2) (p = 0.304), respectively, at the end of the third year. CONCLUSIONS:In patients with limited vertical bone height, short implants with optimized macro-design constitute a reliable method for functional rehabilitation, avoiding extensive alveolar bone augmentation.