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Updated: Feb 6, 2026

Cardiac Magnetic Resonance Imaging at 7 Tesla
Published on: January 6, 2019
A 1-7 year retrospective follow-up on consecutively placed 7-mm-long dental implants with an electrowetted surface
Paul S Rosen1,2, Herman Sahlin3, Rudolf Seemann4
1Clinical Professor of Periodontics, Baltimore College of Dental Surgery, University of Maryland Dental School, Baltimore, MD, USA. paul@psrperioimplant.com.
Background:
This retrospective consecutive case series study was performed to determinate the survival rate and implant stability of short (7 mm length) dental implants with an electrowetted hydrophilic surface that were in function from 1 to 7 years.
Methods:
A retrospective chart review identified and evaluated 86 consecutively placed 7-mm-long dental implants (ProActive, Neoss Ltd., Harrogate, England) in 75 patients. Analysis was performed for implant survival as well as implant stability, as measured by insertion torque (IT) and resonance frequency analysis (RFA).
Results:
Clinical follow-ups were performed from 1.0 to 7.0 years after implant placement (mean 4.0 ± 2.1 years). Two implants failed prior to loading resulting in a 5-year cumulative survival rate (CSR) of 97.7%. An additional late failure occurred at 60 months post-loading for a 7-year CSR of 94.8%. Mean insertion torque was 30.1 ± 7.4 Ncm and mean RFA at insertion was 73.6 ± 8.1 ISQ. Follow-up RFA measurements suggested that the achieved primary stability was maintained throughout the healing phase.
Conclusion:
The present study demonstrates that treatment with short implants can be a predictable treatment option with high survival rate in sites with limited available bone.
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