Peri-Implant Tissue Health and Prosthodontic Outcomes of a Cylindrical-Conical Implant with a Progressive Thread...

We aim to assess the 5-year clinical outcomes of a cylindrical-conical implant system with a progressive thread design and a sandblasted, acid-etched surface and its fixed prostheses under routine clinical conditions.

This retrospective single-center cross-sectional follow-up study included patients treated with implants with a progressive thread design and an internal butt-joint connection between January 2019 and August 2020 at a specialist referral practice in Germany. Of 112 patients treated, 44 (94 implants with fixed restorations) attended the five-year recall. Outcomes were the Functional Implant Prosthodontic Score (FIPS), peri-implant tissue health parameters (bleeding on probing, suppuration, dehiscence, width of keratinized mucosa, and other signs of inflammation), marginal bone level on periapical radiographs, and implant survival.

All 94 implants available for examination remained in situ at five years, corresponding to 100% survival among recalled implants. Mean FIPS was 7.6 out of 10 (interproximal 1.3, occlusion 1.8, design 1.6, mucosa 1.4, bone 1.5). Bleeding on probing was absent in 37.2% of implants and present at ≥3 of 6 sites in 30.9%; suppuration was absent in all cases. Bleeding was descriptively more frequent where keratinized mucosa was narrow: implants with <2 mm bled at nearly three times as many sites as those with ≥2 mm. No implant showed a marginal bone level ≥2.0 mm apical to the shoulder.

Within the limitations of this retrospective cross-sectional follow-up study, the implant system with a progressive thread design demonstrated favorable 5-year prosthodontic, biological and radiological findings under referral-practice conditions.