A retrospective comparison of oxidized and turned implants with respect to implant survival, marginal bone level and peri-implant soft tissue conditions after at least 5 years in function

Abstract

Background: Long-term clinical follow-up studies comparing different implant surfaces with regard to survival and marginal conditions are rare.

Objectives: The objective of this study was to compare the clinical performance of turned and oxidized implants after more than 5 years of loading.

Material and methods: One hundred three patients (43 men, 60 women; mean age 67.4 years, range 32-90) previously treated with 287 implants (Nobel Biocare AB, Gothenburg, Sweden), 133 with turned surface (MKIII, Nobel Biocare AB) and 154 with an oxidized surface (MKIII, TiUnite, Nobel Biocare AB) were examined after at least 5 years of loading (mean 82 months, range 60-93 months). The implants had been used for support of single crowns (33 patients/36 implants), partial bridges (39 patients/103 implants), or full bridges (31 patients/148 implants) following an early loading protocol (14 patients /54 implants), a one-stage protocol (32 patients/59 implants) or a two-stage protocol (57 patients/174 implants). Clinical examinations of bleeding on probing (BoP) and pocket depth (PD) were performed. Intraoral radiographs were used for assessments of marginal bone levels (MBLs).

Results: Seven turned implants and one oxidized implant failed, giving overall cumulative survival rates of 94.7 and 99.4%, respectively. There were no differences for BoP scores (0.5 ± 0.7 vs 0.4 ± 0.6) and PD measurements (1.7 ± 0.8 mm vs 1.8 ± 1.0 mm) parameters when comparing turned and oxidized implants, respectively. The mean MBL was 1.8 ± 0.8 mm and 2.0 ± 0.9 mm for turned and oxidized implants, respectively, after more than 5 years in function (NS). Frequency distribution of MBL loss showed no statistically significant differences between the two surfaces. A total of four implants (1.4%) (three oxidized and one turned) showed a PD > 3 mm, MBL > 4 mm, and BoP. However, none of these were associated with suppuration on examination.

Conclusion: The present study does not state any differences in implant failure, MBL, presence of bleeding or PD around implants when comparing turned and oxidized titanium implants after at least 5 years of function.

Keywords: dental implants; implant survival; long term; oxidized surface; surface characterization; turned surface.