Marginal Bone Loss around Implants with Internal Hexagonal and Internal Conical Connections: A 12-Month Randomized Pilot Study

Abstract

The aim of this study was to analyze the differences in terms of the marginal bone level (MBL) around implants with either an internal conical or an internal hexagonal implant–prosthesis connection. A randomized clinical trial included patients in need of a single implant-supported restoration. The implant–prosthesis connection was either internal conical or internal hexagonal while maintaining the same type of implant macro- and microarchitecture. Clinical and radiographical variables were registered up to 12 months of follow-up, including MBL. A total of 30 patients were included in the study. The main outcome variable, MBL 12 months after prosthesis delivery, was statistically different in both groups: −0.25 (0.12) vs. −0.70 (0.43) (conical vs. hexagonal; p = 0.033). Differences were also observed at the 3- and 6-month follow-up visits as well as for the MBL change from prosthesis delivery to the 12-month follow-up (−0.15 (0.13) vs. −0.56 (0.44); conical vs. hexagonal; p = 0.023). Correlations between MBL around the implants and radiographic measurements on the adjacent teeth, buccal bone to implant, tissue thickness or keratinized tissue were not significant neither globally nor when analyzed independently by group. In view of such results, it can be concluded that single-unit restorations with internal hexagonal-connection implants induce higher marginal bone loss after 12 months of follow-up from prosthesis delivery than internal conical-connection implants.

Early marginal bone loss around dental implants to define success in implant dentistry: A retrospective study

“…The literature clearly indicates that external connection implants show more bone loss than internal connection implants 19‐21 . Also that internal conical connections show less bone loss in vitro and in vivo compared to any other type of connection 22 or even clinically, less marginal bone loss than other internal connection as internal hexagonal connections 23 . Therefore, we understand that it is necessary to update the concepts of HBL and LBL, by extending the analysis to all bone locations and analyzing only implants with conical internal connection, because it is one of the safest connections in terms of bone preservation according to our current understanding of prevention of MBL.…”

Is the clinical performance of internal conical connection better than internal non‐conical connection for implant‐supported restorations? A systematic review with meta‐analysis of randomized controlled trials

“…Many ICC implants exhibit a platform switching design, 36 which contributes to the centralization of stresses in the long axis of the implant 37,38 and reduces stresses in the peri-implant region. In addition, the stabilization of the conical connection reduces micro-movement between the implant/abutment when compared to non-conical connection implants, 22,33,36 which also contributes to the superiority of these implants.…”

Influence Of Conical Versus Trilobe Implant Abutment Connection on Marginal Bone Loss, Soft Tissue Health and Prosthetic Maintenance in Mandibular Implant- Assisted Overdenture: A 3-Year Prospective Split-Mouth Randomized Clinical Trial

“…Few studies evaluated clinically the effect of IAC on either marginal bone loss, periimplant soft tissue or prosthetic maintenance. [46][47][48] .…”