Two-year outcomes of tissue-level and bone-level two-piece zirconia implants : a case series

Žarković Gjurin, Sonja (author), Povšič, Katja (author), Kobe, Tom (author), Žužek, Borut (author), Gašperšič, Rok (author), Oblak, Čedomir (author)

Background/objectives: Zirconia dental implants are increasingly recognised as an alternative to titanium implants due to their biocompatibility and aesthetics. Initially developed as one-piece systems, zirconia implants have evolved into two-piece designs with different platform levels; however, comparative data on their primary and secondary stability– particularly as assessed by resonance frequency analysis (RFA)—and marginal bone dynamics remain limited. This case series aimed to evaluate the implant stability and marginal bone changes of two-piece zirconia implants with bone-level (BL) and tissue-level (TL) platforms in patients missing maxillary premolars. Methods: Thirteen zirconia implants (n = 13; 7 BL, 6 TL; Z5-TL/Z5-BL, Z-Systems, Switzerland) were placed in 11 patients with healed ridges. The implant stability quotient (ISQ) was measured immediately after insertion and before prosthetic loading. Lithium disilicate crowns were cemented after four months, and follow-ups were conducted for an average of 35 months (SD = 12). Results: Initial ISQ values ranged from 73 to 79, increasing to 76–84 at 3–4 months, indicating high implant stability for both BL and TL implants. The extent of marginal bone loss (MBL) after two years was greater around BL implants (mean 0.46 mm) compared to TL implants (mean 0.2 mm), although probing depths and bleeding on probing remained minimal in both groups, with only one TL implant showing gingival recession. Conclusions: Over a short observation period, two-piece zirconia implants with tissue-level platforms appeared to demonstrate superior marginal tissue stability. Further, larger-scale controlled studies are required to confirm these preliminary observations.

• Language: English
• Keywords: zirconia implants, ceramic, two-piece, bone-level, tissue-level, implant stability, ISQ
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: MF - Faculty of Medicine
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: 12 str.
• Numbering: Vol. 6, iss. 1
• PID: 20.500.12556/RUL-185472
• UDC: 616.31
• ISSN on article: 2673-6373
• DOI: 10.3390/oral6010001
• COBISS.SI-ID: 264750083
• Publication date in RUL: 06.08.2026

Record is a part of a journal

• Title: Oral
• Shortened title: Oral
• Publisher: MDPI
• ISSN: 2673-6373
• COBISS.SI-ID: 80648451

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: cirkonijevi vsadki, keramika, dvodelni, na ravni kosti, na ravni tkiva, stabilnost vsadka