The Influence of an Ultrasonic Cleaning Protocol for CAD/CAM Abutment Surfaces on Cell Viability and Inflammatory Response In Vitro

Peter Gehrke; Ralf Smeets; Martin Gosau; Reinhard E Friedrich; Elika Madani; Dirk Duddeck; Carsten Fischer; Florian Tebbel; Robert Sader; Philip Hartjen

doi:10.21873/invivo.11527

The Influence of an Ultrasonic Cleaning Protocol for CAD/CAM Abutment Surfaces on Cell Viability and Inflammatory Response In Vitro

In Vivo. 2019 May-Jun;33(3):689-698. doi: 10.21873/invivo.11527.

Authors

Affiliations

¹ Private Practice for Oral Surgery, Ludwigshafen, Germany and Department of Postgraduate Education, Master of Oral Implantology, Oral and Dental Medicine, Johann Wolfgang Goethe-University, Frankfurt, Germany dr-gehrke@prof-dhom.de.
² Department of Oral and Maxillofacial Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
³ Department of Oral and Maxillofacial Surgery, Division of Regenerative Orofacial Medicine, University Hospital Hamburg-Eppendorf, Hamburg, Germany.
⁴ Medical Materials Research Institute, Berlin, Germany.
⁵ Dental Laboratory, Sirius Ceramics, Frankfurt am Main, Germany.
⁶ Mechanical Engineering, Heddesheim, Germany.
⁷ Department for Oral, Cranio-Maxillofacial and Facial Plastic Surgery, Medical Center of the Goethe University, Frankfurt, Germany.

Abstract

Background/aim: To evaluate the effect of an ultrasonic cleaning and disinfection method for CAD/CAM abutment surfaces on cell viability and inflammatory response in vitro.

Materials and methods: Untreated and manually polished surfaces of CAD/CAM generated titanium and zirconia disks were randomly assigned, either to a 3-step ultrasonic cleaning and disinfection process (test: TiUF, TiPF, ZrUF, ZrPF) or to 30 sec steam cleaning (control: TiUS, TiPS, ZrUS, ZrPS). Pre-cleaning surface analyses using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and surface profilometry were performed. Human gingival fibroblasts (HGFs) were cultured on test and control specimens and subsequently examined for cell viability and inflammatory response. Expression of acute inflammatory cytokine interleukin (IL)-6 and vascular endothelial growth factor A (VEGFA) were assessed by means of RT-qPCR.

Results: Cells on all specimens exhibited a satisfactory viability, indicating firm attachment. Cells on polished zirconia samples, cleaned by means of sonication (ZrPF), exhibited significantly higher viability than cells on the same material cleaned by steam (ZrPS), p=0.019. For all other three material/ surface treatment combinations (TiU, TiP, ZrU), no such difference was observed between the cleaning methods. The messenger ribonucleic acid (mRNA) levels of IL-6 and VEGFA were between 50 and 105% of that of the control cells on the non-toxic control surface. mRNA levels of IL-6 and VEGFA correlated well with each other.

Conclusion: Except for higher viability of cells cultured on polished zirconia specimens, no universally applicable advantage could be found for the ultrasonic cleaning procedure for zirconia and titanium abutment surfaces regarding cell viability, IL-6 expression or VEGFA expression. The cleaning procedures did not have any negative effect either.

Keywords: CAD/CAM implant abutments; cell viability; inflammatory response; steam cleaning; ultrasonic cleaning.

MeSH terms

Biomarkers
Cell Culture Techniques
Cell Survival*
Computer-Aided Design*
Disinfection / instrumentation
Disinfection / methods*
Fibroblasts
Gene Expression
Humans
Sonication* / instrumentation
Sonication* / methods
Surface Properties

Substances

Biomarkers