Effect of platform switching on peri-implant bone levels: a randomized clinical trial
Article first published online: 15 FEB 2011
© 2011 John Wiley & Sons A/S
Clinical Oral Implants Research
Volume 22, Issue 10, pages 1185–1192, October 2011
How to Cite
Enkling, N., Jöhren, P., Klimberg, V., Bayer, S., Mericske-Stern, R. and Jepsen, S. (2011), Effect of platform switching on peri-implant bone levels: a randomized clinical trial. Clinical Oral Implants Research, 22: 1185–1192. doi: 10.1111/j.1600-0501.2010.02090.x
- Issue published online: 12 SEP 2011
- Article first published online: 15 FEB 2011
- Date: , Accepted 15 September 2010
- bone level;
- bone loss;
- dental implants;
- implant design;
- platform switching
Objective: The concept of platform switching has been introduced to implant dentistry based on observations of reduced peri-implant bone loss. However, randomized clinical trials are still lacking. This study aimed to test the hypothesis that platform switching has a positive impact on crestal bone-level changes.
Material and methods: Two implants with diameters of 4 mm were inserted epicrestally into one side of the posterior mandibles of 25 subjects. After 3 months of submerged healing, the reentry surgery was performed. On the randomly placed test implant, an abutment 3.3 mm in diameter was mounted, resulting in a horizontal circular step of 0.35 mm (platform switching). The control implant was straight, with an abutment 4 mm in diameter. Single-tooth crowns were cemented provisionally. All patients were monitored at short intervals over the course of 1 year. Standardized radiographs and microbiological samples from the implants' inner spaces were obtained at baseline (implant surgery), and after 3, 4, and 12 months.
Results: After 1 year, the mean radiographic vertical bone loss at the test implants was 0.53±0.35 mm and at the control implants, it was 0.58±0.55 mm. The mean intraindividual difference was 0.05±0.56 mm, which is significantly <0.35 mm (P=0.0093, post hoc power 79.9%). The crestal bone-level changes depended on time (P<0.001), but not on platform switching (P=0.4). The implants' internal spaces were contaminated by bacteria, with no significant differences in the total counts between the test and the control at any time point (P=0.98).
Conclusions: The present randomized clinical trial could not confirm the hypothesis of a reduced peri-implant bone loss at implants restored according to the concept of platform switching.
To cite this article: Enkling N, Jöhren P, Klimberg V, Bayer S, Mericske-Stern R, Jepsen S. Effect of platform switching on peri-implant bone levels: a randomized clinical trial. Clin. Oral Impl. Res. 22, 2011; 1185–1192. doi: 10.1111/j.1600-0501.2010.02090.x