The Effect of Initial Biologic Width on Marginal Bone Loss: A Retrospective Study.

Area of Science:

• Dental Implantology
• Periodontology
• Oral Surgery

Background:

• Marginal bone loss is a critical factor in long-term dental implant success.
• Understanding factors influencing bone loss, such as soft tissue thickness and implant positioning, is essential for predictable outcomes.

Purpose of the Study:

• To assess the short-term impact of dental implant placement depth and mucosa thickness on marginal bone loss.
• To evaluate the combined effect of these factors, termed initial biologic width, on crestal bone changes.

Main Methods:

• Retrospective analysis of 413 dental implants in 266 patients, loaded for over 12 months.
• Radiographic evaluation of mucosa thickness, implant placement depth, and marginal bone loss.
• Categorization into four groups based on initial biologic width quartiles.

Main Results:

• Implants with an initial biologic width between 2.85 and 3.40 mm exhibited significantly less crestal bone loss.
• Thicker mucosa and implants placed at the bone crest were associated with reduced marginal bone loss compared to thin mucosa and subcrestal placement.
• Specific bone loss values were 0.35 mm median overall, with variations based on implant system and group.

Conclusions:

• Initial biologic width is a significant determinant of short-term marginal bone loss around dental implants.
• An initial biologic width of 2.85–3.40 mm appears optimal for minimizing bone loss.
• Clinical recommendations include prioritizing thick mucosa and placing implants at the bone crest to reduce alveolar bone loss.