Dieter Bosshardt1,*; Urs Brodbeck2; Florian Rathe3; Thomas Stumpf3; Paul Weigl4; Markus Schlee3,5

1Periodontology, University of Bern, Bern; 2Private Practice, Zürich, Switzerland; 3Private Practice, Forchheim; 4Medical Technology Research, Carolinum University Dental Institute; 5Maxillofacial Surgery, Goethe University, Frankfurt am Main, Germany

Background: Peri-implantitis is a frequent biological complication. Numerous methods of implant surface decontamination have been tested and applied. However, none of the surface decontamination methods tested so far have proven to be superior. Very recently, re-osseointegration of contaminated implant surfaces was demonstrated after electrolytic cleaning in a preclinical study. Proof of this concept in humans, however, is missing.

Aim/Hypothesis: To evaluate whether the electrolytic cleaning technique together with regenerative therapy can achieve re-osseointegration of dental implants that developed peri-implantitis in humans.

Material and Methods: In a large clinical study, dental implants that developed peri-implantitis underwent electrolytic cleaning followed by regenerative therapy with guided bone regeneration. Four implants developed recurrent peri-implantitis with implant exposure and explantation was indicated 6 to 13 months after treatment. Radiographic bone level, probing depth, and bleeding on probing were determined at the time of surgery, 6 months later, and before implant retrieval. The peri-implant tissues were histologically and histomorphometrically analyzed.

Results: All four implants demonstrated radiographic and histological bone gain, reduced probing depth and bleeding on probing. Radiographic bone gain was 5.8 mm mesially and 4.8 mm distally for implant #1, 3.3 mm and 2.3 mm for implant #2, 3.1 mm and 0.5 mm for implant #3, and 3.5 mm and 2.8 mm for implant #4. The histometric mean and maximum vertical bone gain for implant #1 to #4 was 1.65 mm and 2.54 mm, 3.04 mm and 3.47 mm, 0.43 mm and 1.27 mm, and 4.15 mm and 5.21 mm, respectively. In one implant, the newly formed bone was deposited directly onto calculus on the implant surface.

Conclusion and Clinical implications: Re-osseointegration of dental implants was proven in humans after electrolytic cleaning and regenerative therapy of peri-implantitis. New bone formation on residual calculus indicated that the electrolytic cleaning process had an effective decontamination effect.

Disclosure of Interest: D. Bosshardt: None Declared, U. Brodbeck Conflict with: financial interest, Conflict with: product inventor, F. Rathe: None Declared, T. Stumpf: None Declared, P. Weigl: None Declared, M. Schlee Conflict with: Consultant, Conflict with: financial interest

Keywords: dental implants, osseointegration, peri-implantitis