Marginal bone level changes in association with different vertical implant positions: a 3-year retrospective study

Area of Science:

• Dental Implantology
• Periodontology
• Radiology

Background:

• Marginal bone loss is a critical factor in long-term dental implant success.
• The implant-abutment interface (IAI) is a key anatomical landmark influencing peri-implant bone health.
• Understanding the IAI's vertical position relative to bone level is crucial for predicting bone maintenance.

Purpose of the Study:

• To investigate the association between the vertical position of the implant-abutment interface and marginal bone loss.
• To evaluate this relationship over a 3-year period using radiological analysis.

Main Methods:

• Retrospective analysis of 286 implant surfaces from 143 implants in 61 patients.
• Classification of implants into three groups based on IAI vertical position: above, at, or below bone level.
• Radiographic assessment of marginal bone levels at baseline and 6, 12, and 36 months post-loading.

Main Results:

• At 36 months, marginal bone loss was 0.99±1.45 mm (above), 1.13±0.91 mm (at), and 1.76±0.78 mm (below) bone level.
• Significantly greater marginal bone loss was observed when the IAI was positioned below the bone level (Group C) compared to Groups A and B.
• Radiological analysis confirmed a dose-dependent relationship between IAI submersion and bone loss.

Conclusions:

• The vertical positioning of the implant-abutment interface significantly influences marginal bone level changes.
• Subgingival placement of the IAI below the marginal bone is associated with increased bone loss.
• Further longitudinal studies are warranted to confirm these findings and guide clinical practice.