Is Implant Surface Roughness a Risk for Periimplantitis?

Introduction

Periimplantitis is a chronic inflammatory condition that affects the bone and soft tissues around a dental implant after successful osseointegration. While bacterial infection is a known cause, the role of implant surface characteristics—particularly surface roughness—has been widely debated.

This systematic review explores whether implant surface roughness increases the risk of periimplantitis, based on current clinical studies.

Why Surface Roughness Matters

Successful osseointegration relies on direct bone-to-implant contact (BIC). Surface roughness enhances BIC by improving mechanical interlocking and promoting cell adhesion. However, rough surfaces can also attract and retain more bacteria, increasing the risk of periimplant disease.

Surface roughness is measured using Sa values (arithmetic mean height deviations from the surface), with classifications as follows:

• Smooth: Sa < 0.5 µm
• Minimally rough: Sa 0.5–1.0 µm
• Moderately rough: Sa 1.0–2.0 µm
• Rough: Sa > 2.0 µm

Review Methodology

This review followed the PRISMA guidelines for systematic reviews. Clinical studies with at least 15 patients and a clear definition of periimplantitis were included. Studies had to provide surface characteristics and clinical or radiographic data.

Out of 4,690 articles initially identified, 22 met all inclusion criteria.

Findings: Roughness and Periimplantitis

Minimally Rough Surfaces (Sa 0.5–1.0 µm)

• Mean periimplantitis rate: 0.57%
• In most studies, periimplantitis was rare or absent.
• Machined surfaces had the lowest risk.

Moderately Rough Surfaces (Sa 1.0–2.0 µm)

• Mean periimplantitis rate: 3.43%
• Results varied based on surface treatment:
  • Sandblasted only: 2.38%
  • Sandblasted + acid-etched (SLA): 3.41%
  • Anodic oxidation: 4.14%

Rough Surfaces (Sa > 2.0 µm)

• Mean periimplantitis rate: 12.86%
• Highest rates observed with titanium plasma-sprayed (TPS) surfaces.

Fig. 1. Periimplantitis rates based on roughness level.

Impact of Surface Treatments

Different surface treatments influence roughness and microbial behavior:

• Machined surfaces: Smooth, less plaque-retentive.
• Sandblasted (1.1 µm): Low periimplantitis, favorable BIC.
• Anodic oxidation (1.1 µm): Higher inflammation and periimplantitis.
• SLA surfaces (1.75 µm): Higher periimplantitis than sandblasted alone.
• TPS surfaces (>2.0 µm): Highest incidence of disease.

Fig. 2. Periimplantitis rates by surface treatment.

Effect of Follow-Up Duration

• 1–5 years:
  • Minimally rough: 0.11%
  • Moderately rough: 3.04%
  • Rough: 12.04%
• 6–10 years:
  • Rough surfaces: up to 15.4%
• 11+ years:
  • TPS surfaces: as high as 20%
  • Smooth and moderately rough surfaces remained stable over time

Clinical Discussion

Rough surfaces may offer better early stability but at a cost. As time progresses, the same surface features that encourage osseointegration can harbor more bacteria and biofilm.

Surface treatment method matters as much as roughness level. For example, anodic oxidation appears to increase risk compared to subtraction-based treatments like sandblasting.

Despite heterogeneity among studies, the trend is clear: higher roughness increases the risk of periimplantitis.

Conclusion

Based on current evidence, implant surface roughness is directly linked to periimplantitis risk. Machined and lightly roughened surfaces carry the lowest risk, while rough surfaces, especially those treated with TPS or anodic oxidation, show significantly higher rates of inflammation and bone loss.

Clinicians should carefully consider the surface characteristics of implants, especially for patients with periimplantitis risk factors. When long-term implant health is a priority, smoother surfaces remain the safer option.

The original article published by: 

Fabienne Jordana, MSc, DDS, PhD, Léa Susbielles, DDS, and Jacques Colat-Parros, MSc, DDS, PhD