Concave emergence profile reduces gum recession around dental implants
Three-year RCT shows concave emergence profiles reduce gum recession around anterior implants.
Three-year study on emergence profile design
A randomised controlled trial by Endres et al. (2025) compared convex and concave emergence profiles in implant-supported crowns placed in the aesthetic zone over three years. The study included 47 patients requiring single-tooth replacement in the anterior region (incisors, canines, or premolars). Patients were randomly assigned to receive either a convex emergence profile, a concave emergence profile, or standard healing abutment (control). All crowns were placed using a standardised surgical protocol and digital design. Measurements were taken at baseline, six months, one year, and three years.
Concave design shows better soft tissue stability
After three years, 42 of 47 patients were re-evaluated. The convex group showed significantly higher odds of midfacial mucosal recession compared to the concave group. At one year, the odds ratio was 13.3 (95% CI: 1.2-138.5; p = 0.003), and at three years it was 7.3 (95% CI: 1.02-52.14; p = 0.048), after correction for soft tissue thickness and keratinised gingiva width. No significant differences emerged between the convex group and control group. Clinical parameters including pocket depth, bleeding on probing, peri-implantitis, and radiographic bone loss showed no significant differences between groups at three years. Pink Esthetic Score also did not differ significantly between groups.
Clinical implications for aesthetic implant restoration
The results indicate that a concave emergence profile better protects peri-implant soft tissues and prevents recession in the anterior region. The emergence profile appears to influence mucosal tissues more than bone-level outcomes. Study limitations include small sample size, dropout during follow-up, and focus only on the aesthetic zone without bone augmentation. The three-year follow-up and randomised design strengthen the findings. Clinically, these results support using a concave contour where anatomically and prosthodontically feasible, to preserve marginal soft tissue stability and long-term aesthetics. Future research should explore these principles in augmented sites, posterior regions, and larger populations with extended follow-up periods.
Frequently asked questions
Does concave or convex emergence profile prevent more gum recession around implants?
A three-year randomised controlled trial found that concave emergence profiles significantly reduced midfacial mucosal recession compared to convex profiles. At one year, patients with convex profiles had 13.3 times higher odds of recession, and at three years the odds ratio was 7.3, after adjusting for soft tissue thickness and keratinised gingiva width.
What is emergence profile in implant dentistry?
The emergence profile is the contour where an implant-supported crown transitions from tooth to gingiva. It can be shaped as convex (bulging outward) or concave (curving inward). The shape influences how well the soft tissues adapt and remain stable over time.
Does emergence profile affect bone loss around implants?
No. The Endres study found no significant differences in radiographic marginal bone loss, pocket depth, or bleeding on probing between convex and concave emergence profiles at three years. The emergence profile primarily influences soft tissue (mucosal) stability rather than bone-level outcomes.
Should all anterior implant crowns use concave emergence profiles?
According to the study, a concave emergence profile is clinically preferable for long-term soft tissue and aesthetic stability in the anterior region, provided it is anatomically and prosthodontically feasible. However, the study was limited to cases without bone augmentation and the aesthetic zone, so application in other situations requires further research.
What was the follow-up period in this implant emergence profile study?
The study followed patients for three years, with measurements taken at baseline (7-10 days after crown placement), six months, one year, and three years. Of the 47 enrolled patients, 42 completed the full three-year evaluation.
