Influence of implant-abutment connection structure on peri-implant bone level in a second molar: A 1-year randomized controlled trial

Jin Cheol Kim, Jungwon Lee, Sungtae Kim, Ki Tae Koo, Hae Young Kim, In Sung Luke Yeo

Research output: Contribution to journalArticlepeer-review

8 Citations (Scopus)


PURPOSE. This study aimed to evaluate the effect of two different implant-abutment connection structures with identical implant design on peri-implant bone level. MATERIALS AND METHODS. This clinical study was a patient-blind randomized controlled trial following the CONSORT 2010 checklists. This trial was conducted in 24 patients recruited between March 2013 and July 2015. Implants with internal friction connection were compared to those with external hex connection. One implant for each patient was installed, replacing the second molar. Implant-supported crowns were delivered at four months after implant insertion. Standardized periapical radiographs were taken at prosthesis delivery (baseline), and one year after delivery. On the radiographs, distance from implant shoulder to first bone-to-implant contact (DIB) and peri-implant area were measured, which were the primary and secondary outcome, respectively. RESULTS. Eleven external and eleven internal implants were analyzed. Mean changes of DIB from baseline to 1-year postloading were 0.59 (0.95) mm for the external and 0.01 (0.68) mm for the internal connection. Although no significant differences were found between the two groups, medium effect size was found in DIB between the connections (Cohen's d = 0.67). CONCLUSION. Considering the effect size in DIB, this study suggested the possibility of the internal friction connection structure for more effective preservation of marginal bone.

Original languageEnglish
Pages (from-to)147-154
Number of pages8
JournalJournal of Advanced Prosthodontics
Issue number3
Publication statusPublished - 2019

Bibliographical note

Funding Information:
The authors report grants and non-financial support from Shinhung Corporation, Seoul, Korea (Grant No.: NCR13002). This work was also supported by the Mid-Career Researcher Program through a grant from the National Research Foundation of Korea, funded by the Korean government (MSIP) (2016R1A2B4014330).

Publisher Copyright:
© 2019 The Korean Academy of Prosthodontics.


  • Alveolar bone loss
  • Dental implant-abutment design
  • Randomized controlled trial

ASJC Scopus subject areas

  • Oral Surgery
  • Dentistry (miscellaneous)


Dive into the research topics of 'Influence of implant-abutment connection structure on peri-implant bone level in a second molar: A 1-year randomized controlled trial'. Together they form a unique fingerprint.

Cite this