At 5-year follow-up, the overall SBI was 0.32 ± 0.49, reflective of no bleeding given that 0 equals no bleeding and 1 equals isolated bleeding spots visible [27]. The PPD initially decreased within the first 6 months from which point it significantly increased to 2.34 ± 1.18 mm at 5-year follow-up.

Nevertheless, the measured mean PPD still reflects the norm for conventionally placed implants, which at 2–4 mm is indicative of healthy tissues [35]. The same trend was observed for the Jemt papilla score [28], which significantly increased from loading to 5-year follow-up (2.14 ± 0.95). The ideal papilla score of 3 [28]corresponds to the optimal soft tissue contours; thus, the scores achieved in our study are close to the ideal. Although we observed some significant differences in these parameters between the platform-switching and platform-matching subgroups at 5 years, these are not clinically significant.

Our study should be particularly noted for its ability to recall patients for follow-up appointments. Patient attendance at follow-up appointments in trials performed in private practice can be troublesome [4, 6,7,8], and the inability to obtain full data from all patients at the later stages of a study may limit the interpretation of the final results. We obtained data for the 70% of patients completing the study at 5 years; this minimizes the limitations in the interpretation of results seen in comparable studies [5,6,7,8]. Although this study was performed in private practice, the investigators are very experienced in implantology and of good standing and understand the importance of follow-up and maintenance of good oral health. We observed a maximum of only five patients with poor oral hygiene at any given time (data not shown); additionally, the three late implant failures were in two patients with peri-implantitis or poor hygiene.