J Periodontal Implant Sci.  2022 Dec;52(6):496-508. 10.5051/jpis.2200960048.

Long-term effect of implant-abutment connection type on marginal bone loss and survival of dental implants

• Kim YM
• Lee JB
• Um HS
• Chang BS
• Lee JK

• KMID: 2557547
• DOI: http://doi.org/10.5051/jpis.2200960048

Abstract

Purpose
This study aimed to compare the long-term survival rate and peri-implant marginal bone loss between different types of dental implant–abutment connections.
Methods
Implants with external or internal abutment connections, which were fitted at Gangneung-Wonju National University Dental Hospital from November 2011 to December 2015 and followed up for >5 years, were retrospectively investigated. Cumulative survival rates were evaluated for >5 years, and peri-implant marginal bone loss was evaluated at 1- and 5-year follow-up examinations after functional loading.
Results
The 8-year cumulative survival rates were 93.3% and 90.7% in the external and internal connection types, respectively (P=0.353). The mean values of marginal bone loss were 1.23 mm (external) and 0.72 mm (internal) (P<0.001) after 1 year of loading, and 1.20 mm and 1.00 mm for external and internal abutment connections, respectively (P=0.137) after 5 years. Implant length (longer, P=0.018), smoking status (heavy, P=0.001), and prosthetic type (bridge, P=0.004) were associated with significantly greater marginal bone loss, and the use of screw–cement-retained prosthesis was significantly associated (P=0.027) with less marginal bone loss.
Conclusions
There was no significant difference in the cumulative survival rate between implants with external and internal abutment connections. After 1 year of loading, marginal bone loss was greater around the implants with an external abutment connection. However, no significant difference between the external and internal connection groups was found after 5 years. Both types of abutment connections are viable treatment options for the reconstruction of partially edentulous ridges.

Keyword

Alveolar bone loss; Dental implant-abutment design; Dental implants; Survival rate