Characteristics of implant‐CAD/CAM abutment connections of two different internal connection systems

Abstract

Titanium or zirconium computer-aided design/computer-aided manufacturing abutments are now widely used for aesthetic implant treatments; however, information regarding microscopic structural differences that may influence the biological and mechanical outcomes of different implant systems is limited. Therefore, the characteristics of different connection systems were investigated. Optical microscopic observation and scanning electron microscopy showed different characteristics of two internal systems, namely the Astra Tech and the Replace Select system, and for different materials. The scanning electron microscopic observation showed for the Astra Tech that the implant-abutment interface seemed to be completely sealed for both titanium and zirconium abutments, both horizontally and sagittally; however, the first implant-abutment contact was below the fixture top, creating a microgap, and fixtures connected with titanium abutments showed significantly larger values (23·56μm±5·44 in width, and 168·78μm±30·39 in depth, P<0·001). For Replace Select, scanning electron microscopy in the sagittal direction showed that the sealing of titanium and zirconium abutments differed. The seal between the implant-titanium and implant-zirconium abutments seemed to be complete at the butt-joint interface; however, the displacement of the abutment in relation to the fixture in the lateral direction was evident for both abutments with no statistical differences (P>0·70), creating an inverted microgap. Thus, microscopy evaluation of two commonly used internal systems connected to titanium or zirconium abutments showed that the implant-abutment interface was perfectly sealed under no-loading conditions. However, an inverted microgap was seen in both systems, which may result in bacterial accumulation as well as alteration of stress distribution at the implant-abutment interface.

Implant fracture failure rate and potential associated risk indicators: An up to 12‐year retrospective study of implants in 5,124 patients

“…The internal conical type provides stability through contact between the implant and abutment, which enables a more favorable transmission of force and enhanced resistance to horizontal and oblique forces (Bordin et al, ; Bozkaya & Müftü, ; Machado, Bonfante, Anchieta, Yamaguchi, & Coelho, ; Merz et al, ). However, we found no significant differences between the 2 types of connections, which are similar results to previous experimental outcomes (Sumi et al, ).…”

Implant vs abutment level connection in implant supported screw‐retained fixed partial dentures with cobalt‐chrome framework: 1‐year interim results of a randomized clinical study

“…Compared to external or internal butt joints, conical implantabutment connections exhibit better continuity in yield forces 16,17 and possess high rigidity with low risk for leakage. 18,19 Nevertheless, internal conical connection may present mechanical disadvantages because of the reduced coronal wall thickness of the implant and may therefore have a decreased bearing capacity. 20,21 However, there is no clinical evidence comparing IL and AL setups for screw-retained restoration in implants with conical connection.…”

Intraoral digital impression for fabricating a replica of an implant-supported interim prosthesis

“…Even though some authors have reported that this abutment was clinically acceptable, a careful inspection is required, because combinations of abutments and implants from different manufacturers can result in a misfit at the implantabutment interface. [8][9][10][11][12][13][14][15][16][17] SUMMARY Duplication of the ISIP facilitates the patient's adaptation to the ISDP. Improving the intraoral scanner and CAD program are necessary to simplify the digital workflow.…”

“…With computer-aided design/computer-aided manufacturing (CAD/CAM) technology, a customized abutment can also be applied to control the emergence profile. [8][9][10][11][12][13][14][15][16][17] Digital impression has become possible with the development of intraoral scanner systems. 1,[18][19][20][21][22] Recently, Joda et al 21 and Hinds 22 introduced digital impression techniques using a customized scannable impression coping to transfer the supraimplant soft tissue outline.…”