Cytocompatibility of Titanium, Zirconia and Modified PEEK after Surface Treatment Using UV Light or Non-Thermal Plasma.

Linna Guo,Ralf Smeets,Lan Kluwe,Martin Gosau,Anders Henningsen,Claudio Cacaci,Mike Barbeck,Philip Hartjen

doi:10.3390/ijms20225596

Abstract

A number of modifications have been developed in order to enhance surface cytocompatibility for prosthetic support of dental implants. Among them, ultraviolet (UV) light and non-thermal plasma (NTP) treatment are promising methods. The objective of this study was to compare the effects of UV light and NTP on machined titanium, zirconia and modified polyetheretherketone (PEEK, BioHPP) surfaces in vitro. Machined samples of titanium, zirconia and BioHPP were treated by UV light and NTP of argon or oxygen for 12 min each. Non-treated disks were set as controls. A mouse fibroblast and a human gingival fibroblast cell line were used for in vitro experiments. After 2, 24 and 48 h of incubation, the attachment, viability and cytotoxicity of cells on surfaces were assessed. Results: Titanium, zirconia and BioHPP surfaces treated by UV light and oxygen plasma were more favorable to the early attachment of soft-tissue cells than non-treated surfaces, and the number of cells on those treated surfaces was significantly increased after 2, 24 and 48 h of incubation (p < 0.05). However, the effects of argon plasma treatment on the cytocompatibility of soft tissue cells varied with the type of cells and the treated material. UV light and oxygen plasma treatments may improve the attachment of fibroblast cells on machined titanium, zirconia and PEEK surfaces, that are materials for prosthetic support of dental implants.

Highlights

Dental implants have become a safe and reliable treatment method in patients with reduced dentition [1,2]
Micro-rough titanium and zirconia surfaces were treated by ultraviolet (UV) light or non-thermal plasma (NTP) in a short time, and the results showed that either method was able to significantly increase the wettability and oxygen content of the surfaces, and decrease the amount of carbon remnants [16,17,18]
Compared to controls, cells on surfaces treated by UV light and oxygen plasma were larger and more elongated (Figure 1), and, after 2, 24 and 48 h of incubation following live–dead staining, the number of cells attached were significantly higher after these treatments (Figure 2)

Summary

Introduction

Dental implants have become a safe and reliable treatment method in patients with reduced dentition [1,2]. The long-term survival and success of dental implants is influenced by various factors [3,4,5]. Soft-tissue adhesion on transmucosal parts of an implant (abutments) plays a key role in the long-term success of dental implants. A good soft-tissue sealing can contribute to reduced bacterial colonization and reduced risk of inflammation [6]. In order to achieve soft-tissue sealing, human gingival fibroblasts (HGFs), which are regarded as the main cell type in peri-implant soft tissues [7], need to adhere to the surface before bacteria, so that a cellular layer can cover the abutment, making the surface less available for bacterial attachment [8,9]. Abutments as transmucosal parts of an implant are expected to achieve early soft-tissue adhesion, demonstrating good soft-tissue biocompatibility. Modifications of implant abutment surfaces have been the focus of recent research [10,11,12]

Objectives

Methods

Discussion

Conclusion