Abstract
This 5-year prospective cohort study aimed to evaluate and compare long-term marginal bone level (MBL) alterations around immediate versus delayed loaded platform-switched dental implants placed in the posterior maxilla. One hundred and twenty patients requiring single or multiple implant-supported restorations in the posterior maxilla were recruited and divided into two groups: immediate loading (IL, n=60) and delayed loading (DL, n=60). All implants utilized a platform-switched design. Standardized periapical radiographs were taken at baseline, 6 months, 1 year, 3 years, and 5 years post-loading to measure MBL changes from the implant shoulder. Clinical parameters, including implant survival rates, probing depth, and bleeding on probing, were also recorded. At 5 years, the overall implant survival rate was 98.3% (IL: 97.5%, DL: 99.1%). The mean MBL change from baseline to 5 years was 0.78 ± 0.21 mm for the IL group and 0.72 ± 0.18 mm for the DL group. Statistical analysis revealed no significant difference in MBL changes between the two groups at any time point (p > 0.05). Both groups demonstrated stable MBL after initial remodeling. This study concludes that immediate loading of platform-switched dental implants in the posterior maxilla offers comparable long-term marginal bone stability to delayed loading, providing a predictable treatment option for reducing treatment time without compromising osseointegration.
