Long-Term Outcomes of Light versus Non-Light Occlusion in Posterior Implant Crowns

The absence of a periodontal ligament in osseointegrated implants increasing its susceptibility to overload-related complications over time. Light occlusion concept is widely advocated to mitigate biomechanical risks, yet robust evidence supporting its long-term superiority is lacking. The objective of this study was to compare the long-term clinical outcomes of posterior implant-crowns restored with light versus non-light occlusion. This retrospective cohort study analyzed data from patients who received posterior implant-crowns and attended follow-up visits >1 y after crown delivery. Patients were categorized into two groups based on the occlusal scheme applied at delivery: light occlusion and non-light occlusion. Statistic modes were used to evaluate implant survival, technical/biological complications, marginal bone loss (MBL), and proximal contact loss (PCL). A total of 382 patients (565 implants) were included, with observation periods ranging from 1 to 11 years. The results indicated comparable outcomes. The cumulative implant survival rates were 90.3% for the light occlusion group and 84.9% for the non-light group (log-rank p=0.62). Similarly, non-technical complication rates did not differ significantly between groups (p=0.66). Multivariable analyses further confirmed that a non-light occlusal scheme was not a significant risk factor for implant failure, technical or biological complications, MBL, or PCL. In conclusion, within the limitations of this study, implant-crowns restored with non-light occlusal scheme demonstrated long-term clinical and radiographic outcomes comparable to those restored with a light occlusal scheme. These findings suggest that routine application of light occlusion may not be essential and that an individualized approach emphasizing established biomechanical and biological risk factors may be more appropriate.