Clinical performance and occlusal wear of polymer-infiltrated ceramic network and zirconia-reinforced ceramic implant-supported single crowns fabricated via a digital workflow on two titanium implant systems: a 12-month prospective randomized trial

Int J Implant Dent. 2026 Feb 20;12(1):10. doi: 10.1186/s40729-026-00671-9.

Abstract

Purpose: Polymer-infiltrated ceramic network (PICN) and zirconia-reinforced lithium silicate (ZLS) ceramics are alternatives for implant-supported single crowns (ISCs). This prospective randomized trial evaluated 12-month survival of PICN- and ZLS-ISCs supported by Straumann Bone Level Tapered (BLT) and CAMLOG Promote plus (PP) titanium implants. Furthermore, technical complications and occlusal wear were analyzed.

Methods: Sixty-one patients received a single titanium implant from two different manufacturers, and one was treated with two implants. All implants were placed using fully guided static computer-assisted surgery. After randomization, screw-retained CAD-CAM ISCs were fabricated from PICN (n = 31) or ZLS (n = 31) and cemented onto stock titanium base abutments. After 1 year, implant and prosthetic survival, material- and system-dependent outcomes, technical complications, and occlusal wear-based on superimposed baseline and follow-up intraoral scans-were recorded. Independent t-tests were performed (p = 0.05).

Results: Forty-two ISCs were evaluated after one year (mean follow-up: 409.5 ± 102.6 days). PICN showed a 84% survival rate, while ZLS achieved 100% survival. Debonding occurred in five restorations (PICN = 2; ZLS = 3). No complications were observed in 86% of PICN and 85% of ZLS crowns. Occlusal wear was significantly greater for PICN (0.45 ± 0.38 mm) compared with ZLS (0.16 ± 0.05 mm; p = 0.03). Both crown fractures occurred on BLT implants (82% survival), whereas PP implants showed 100% survival.

Conclusions: ZLS demonstrated the highest survival rate and no irreparable failures, along with significantly lower occlusal wear. PICN showed more catastrophic fractures and greater wear. Technical complications were frequent for both materials, independent of implant system or abutment height.

Trial registration: Deutsches Register Klinischer Studien (DRKS-ID: DRKS00026973).

Keywords: Ceramics; Digital workflow; Implant; Polymer-infiltrated ceramic network; Survival rate; Zirconia-reinforced lithium silicate ceramic.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Aged
  • Ceramics*
  • Computer-Aided Design
  • Crowns*
  • Dental Implants, Single-Tooth*
  • Dental Prosthesis Design*
  • Dental Prosthesis, Implant-Supported*
  • Dental Restoration Failure
  • Dental Restoration Wear*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Polymers
  • Prospective Studies
  • Titanium
  • Zirconium*

Substances

  • Zirconium
  • zirconium oxide
  • Titanium
  • Polymers