evidence based prospection of switching platform in dental implants

Evidence Based Prospection OfSwitching Platform in Dental Implants

Ziad S. Abdul Majid BDS, Dip.Imp.DentMay / 2015

In an attempt to improve long-term bone maintenance around implants, an implant-to abutment connection referred to as “platform switching” has been proposed.

Overview

The Implant Abutment InterfaceThe “ MICROGAP “

• The connection between implant fixture and its restorative abutment is termed the implant abutment interface (IAI) or “microgap”.

• In most cases, it is susceptible to micromovements during clinical function and also permits micro-leakage of fluids, this infiltration results in the permanent presence of an area of abutment inflammatory cell infiltrate .

• The sustained state of inflammation promotes osteoclast formation and activation, which contributes to bone loss

Lazzara RJ, Porter SS. Platform switching: A new concept in implant dentistry for controlling postrestorative crestal bone levels. Int J Periodontics Restorative Dent 2006;26:9–17.

(Lindhe et al., 1992) “ Evaluated the microgap of the Brånemark 2-stage implant and found inflamed connective tissue existed 0.5 mm above and below the abutment-implant connection, which resulted in 0.5 mm bone loss within 2 weeks after the abutment was connected to the implant ”.

Microgap and The platform-switching concept

Lindhe et al., Clin Oral Implant Res1992;3:9-16.

Factors Contributing to Marginal Bone Loss Around Implants

The remodeling process involves marginal bone resorption that is affected by the following factors:

1. Infectious process.

2. Excessive loading conditions.

3. The location, shape, and size of the implant-abutment microgap and its microbial contamination.

4. Biologic width geometry and implant surface roughness.

5. Peri-implant inflammatory infiltrate.

6. Micro-movements of the implant and prosthetic components.

7. Repeated screwing and unscrewing.

8. Implant-neck.

9. Traumatic surgical technique.

Chrcanovic, Bruno Ramos et al. Platform switch and dental implants: A meta-analysis.Journal of Dentistry 2015

The concept of platform switching was introduced by Lazzara and Porter 2006:

• the use of a smaller-diameter abutment on a larger-diameter implant collar. Through the placement of smaller prosthetic components on the implant platform, the implant-abutment junction is moved inward from the implant shoulder and further away from the bone, shifting the inflammatory cell infiltrate to the central axis of the implant and away from the adjacent crestal bone.


- It was suggested that the inward positioning of the implant-abutment interface allowed the biologic width to be established horizontally, as an additional horizontal surface area is created for soft tissue attachment.


- Less vertical bone resorption is required to compensate for the biologic width.

- This design increases the distance between the inflammatory cell infiltrate at the microgap and the crestal bone, thereby minimizing the effect of inflammation on marginal bone remodeling.


• The mechanism by which platform switching can contribute to maintain the crestal bone height could be due to four reasons:

1. Shifting the inflammatory cell infiltrate inward and away from the adjacent crestal bone.

2. Maintenance of biological width and increased distance of IAJ from the crestal bone level.

How platform switching reduces crestal bone loss ?

Peri-implant bone level around implants with platform-switched abutments. Fickl, S et al. INT J ORAL MAXILLOFAC IMPLANTS 2010;25:577–581

3. The possible influence of micro-gap on the crestal bone is diminished.

4. Decreased stress levels in the peri-implant bone.

Peri-implant bone level around implants with platform-switched abutments. Fickl, S et al. INT J ORAL MAXILLOFAC IMPLANTS 2010;25:577–581

Benefits Of Platform Switching

1. Increased implant longevity.

2. Improved esthetics.

3.The effect of inter-implant distance is minimized. “ A minimum of 3 mm inter-implant distance is needed to preserve marginal bone”.

Serrano-Sánchez P, Calvo-Guirado JL, Manzanera-Pastor E, Lorrio- Castro C, Bretones-López P, Pérez-Llanes JA. The influence of platform switching in dental implants. A literature review. Med Oral Patol Oral Cir Bucal. 2011 1;16 (3):e400-5.

Limitations Of Platform Switching

1. If normal sized abutments are to be used, implants of larger size need to be placed. This might not be possible always clinically.

2. If normal implants are to be used, smaller diameter abutments may compromise the emergence profile in aesthetic areas.


3. Around 3 mm of soft tissue should be present to place platform switched implants or else bone resorption is likely to occur.

4. For platform switching to be effective, the under sizing of the components must be carried out during all phases of the implant treatment.


In Brief Platform switching • Capable of reducing or eliminating crestal bone loss. It also

contributes to maintaining the width and height of crestal bone and the crestal peak between adjacent implants and it also limits the circumferential bone loss.

• Offer multiple advantages and potential applications, which include situations where a larger implant is desirable but the prosthetic space is limited, and in the anterior zone where preservation of the crestal bone can lead to improved aesthetics.

Thank you

evidence based prospection of switching platform in dental implants

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