J Periodontal Implant Sci.  2015 Feb;45(1):23-29. 10.5051/jpis.2015.45.1.23.

Complication incidence of two implant systems up to six years: a comparison between internal and external connection implants

• Chae SW
• Kim YS
• Lee YM
• Kim WK
• Lee YK
• Kim SH

• KMID: 2027829
• DOI: http://doi.org/10.5051/jpis.2015.45.1.23

Abstract

PURPOSE
This study was conducted to compare the cumulative survival rates (CSRs) and the incidence of postloading complications (PLCs) between a bone-level internal connection system (ICS-BL) and an external connection system (ECS).
METHODS
The medical records of patients treated with either a ICS-BL or ECS between 2007 and 2010 at Asan Medical Center were reviewed. PLCs were divided into two categories: biological and technical. Biological complications included >4 mm of probing pocket depth, thread exposure in radiographs, and soft tissue complications, whereas technical complications included chipping of the veneering material, fracture of the implant, fracture of the crown, loosening or fracture of the abutment or screw, loss of retention, and loss of access hole filling material. CSRs were determined by a life-table analysis and compared using the log-rank chi-square test. The incidence of PLC was compared with the Pearson chi-squared test.
RESULTS
A total of 2,651 implants in 1,074 patients (1,167 ICS-BLs in 551 patients and 1,484 ECSs in 523 patients) were analyzed. The average observation periods were 3.4 years for the ICS-BLs and 3.1 years for the ECSs. The six-year CSR of all implants was 96.1% (94.9% for the ICS-BLs and 97.1% for the ECSs, P=0.619). Soft tissue complications were more frequent with the ECSs (P=0.005) and loosening or fracture of the abutment or screw occurred more frequently with the ICS-BLs (P<0.001).
CONCLUSIONS
Within the limitations of this study, the ICS-BL was more prone to technical complications while the ECS was more vulnerable to biological complications.

Keyword

Dental implant-abutment design; Dental implants; Retrospective studies; Survival rate

MeSH Terms

Chungcheongnam-do
Crowns
Dental Implant-Abutment Design
Dental Implants
Humans
Incidence*
Medical Records
Retrospective Studies
Survival Rate
Dental Implants

Figure

• 

  Figure 1 Failure rates according to the position of the implants. The ECSs failed most often in the maxillary anterior region while the ICS-BLs failed most often in the mandibular molar area. ECS: external connection implant system, ICS-BL: bone-level internal connection implant system. *P<0.05.

• 

  Figure 2 Complication incidence in the two implant systems. Soft tissue complications, belonging to the category of biological complications, occurred more often in the ECSs, while loosening or fracture of the abutment or screw was more frequent in the ICS-BLs. PD: periodontal debridement, ECS: external connection implant system, ICS-BL: bone-level internal connection implant system. **P<0.01. ***P<0.001.

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