Impact of implant–abutment connection, positioning of the machined collar/microgap, and platform switching on crestal bone level changes. Camlog Foundation Consensus Report.

Abstract

ObjectivesThe aim of this consensus meeting was to assess the impact of implant–abutment connection, positioning of the machined collar/microgap, and platform switching on crestal bone level changes.Materials and methodsTwo comprehensive systematic reviews were prepared in advance of the meeting. Consensus statements, practical recommendations, and implications for future research were based on within group as well as plenary scrutinization and discussions of these systematic reviews.ResultsPlacing the smooth part of the implant below the alveolar crest may lead to bone loss. Despite a more pronounced bone remodeling, the subcrestal positioning of the microgap may help to retain the bony coverage of the rough surface. Crestal bone remodeling has been observed for either internal and external, or conical and butt–joint connections. There was a trend favoring the platform switching concept to prevent or minimize peri-implant marginal bone loss.ConclusionsFuture research should consider an uniform and comparable study design, either excluding or exactly documenting possible confounding factors.

Early‐predictors of marginal bone loss around morse taper connection implants loaded with single crowns: A prospective longitudinal study

“…Unlike the reports in the literature, the evidence from our study suggests that wearing a small platform diameter was a predictive factor for marginal bone loss. The difference in diameter size between our study and the previous ones might be a reasonable explanation for our divergent findings . Another possible explanation is that in our study the abutments presented equal diameters, regardless of the diameter of the implants.…”

“…The tendency based on our results favors the platform switching technique to prevent or minimize implant marginal bone loss, compared with implants with platform matching abutments. It seems to be an issue only in situations in which a small volume of soft‐tissue thickness is observed around the implant . In addition, implant length above 8.5 mm was associated with increased marginal bone loss, as the increased contact area between the cortical bone and the implant interface results in higher cortical fixation.…”

Can Periimplantitis Be Treated?

“…45 However, in the esthetic zone, it may be prudent to place the implant shoulder 0.5 to 1.0 mm subcrestal 47 so that a proper emergence profile can be achieved. Recent literature also found that subcrestal placement of the microgap 49,50 and the presence of a platform switch 51,52 aid in the preservation of the marginal bone level and, therefore, can be a useful feature in the anterior region where the implant can be placed slightly subcrestal. If the implant is placed too shallow, esthetic complications, such as poor contours of the restoration and visible metal margins, may ensue.…”

Assessment of Marginal Bone Loss around Platform-Matched and Platform-Switched Implants - A Prospective Study

“…Effects of platform switching in limiting the peri-implant MBL have been discussed in both prospective and longitudinal human studies (3,9) and displayed long-term stability (15,16). Conversely, numerous studies have also reported results rejecting the platform-switching concept.…”

“…These results showed that both implants with matched and switched platform presented progressive bone loss. However, comparisons between different time intervals may be crucial to accurately confirm the concept of platformswitching (15). From the time point of prosthesis installation, which created a horizontal inward mismatch for the test group, to 1 year follow-up (T2-T1), a significant hMBL and BLa reduction occurred around switched platform implants and the linear regression showed a trend of higher MBL around matched platform implants over time.…”