# A prospective observational study regarding host-derived immunological parameters around zirconia implants in comparison to natural teeth following flap surgery

## TL;DR

This study compares immune responses around zirconia dental implants and natural teeth in patients who had jaw reconstructions using flap surgery.

## Contribution

The study provides new insights into cytokine levels and implant success rates in jaw reconstructions using zirconia implants.

## Key findings

- Zirconia implants showed cytokine levels comparable to natural teeth in crevicular fluid.
- MMP-8 levels were significantly lower in natural teeth compared to implants in some flap types.
- Implant success rates were affected by the type of flap surgery used.

## Abstract

With the increasing use of dental implants in patients undergoing extensive mandibular reconstructions, it is crucial to understand how soft tissues react in different implantation contexts. The aim was to compare the behavior of the soft tissues surrounding zirconia implants to that of the soft tissues surrounding natural teeth in terms of cytokine levels in patients who had undergone various microvascular flap procedures for jaw reconstruction. Due to anatomical deviations after flap surgery, such as thick skin paddles, the possibility of fixed implant dentures in patients with bony flaps is rare. Therefore, these patients are often treated with removable dentures. In this prospective observational study ten patients with a total of six fibula flaps and four deep circumflex iliac artery (DCIA) flaps underwent reconstruction in the lower and upper jaws using vascularized bone flaps, and were treated with a total of 41 zirconia implants. The cytokine levels in the crevicular fluid were analyzed in terms of the interleukin-1 beta (IL-1b) and matrix metalloproteinase-8 (MMP-8) levels up to one-year follow-up. The implant survival and success rates were also investigated up to one year. No significant differences in IL-1b were found between natural teeth and ceramic implants. After six months, MMP-8 levels of the natural teeth of a patient treated with DCIA flaps were once significantly lower when compared to the ceramic implants inserted into fibula flaps (p = 0.001). The overall survival and success rates were 100 and 76.83%, respectively. For the fibula group, the survival and success rates were 100 and 72.55%, respectively, and for the DCIA group, they were 100 and 81.12%. Zirconia implants and natural teeth showed comparable cytokine levels in the crevicular fluid. Nevertheless, implant treatment with extensive microvascular jaw reconstructions affected the success rates in the present study.