The Open Dentistry Journal

ISSN: ― Volume ,

Surface Roughness and Necessity of Manual Refinishing Requirements of CAD/CAM-Manufactured Titanium and Cobalt-Chrome Bars – A Pilot Study

Peter Gehrke1, *, Jochen Dinkel2, Carsten Fischer3, Kai Schmenger4, Robert Sader5
1 Private Practice for Oral Surgery, Bismarckstraße 27, 67059 Ludwigshafen, Germany / Department of Postgraduate Education, Johann Wolfgang Goethe-University, Frankfurt, Germany
2 Private Practice, Mittelstrasse 1, 67240 Bobenheim-Roxheim, Germany
3 Sirius Ceramics Laboratory, Lyoner Strasse 44-48, 60528, Frankfurt, Germany
4 VISUAL-BiOLOGY, Hambacher Tal 7, 64646 Heppenheim, Germany
5 Department for Oral, Cranio-Maxillofacial and Facial Plastic Surgery, Medical Center of the Goethe University, Frankfurt, Germany



Due to their increased precision, CAD/CAM generated bars (Computer-Aided Design/ Computer-Aided Manufacturing) are increasingly utilized in implant prosthodontics. For optimal clinical results, surface morphology should promote the integration of soft tissue while minimizing plaque and bacterial retention.


Despite their clinical use, only limited information on the biological and clinical surface quality of CAD/CAM milled bars is available. The aim of the study was therefore to characterize the surface topography of bars of different manufacturers based on the profilometric analysis and the need for manual post-processing in the laboratory.


A custom mandibular edentulous cast with four anterior implants was used as a reference cast and reproduced eight times. On each reproduction cast, corresponding scan flags were positioned and digitized. Acrylic 3D printed bar frameworks were produced and sent to the respective production center along with the digital files of the CAD bars for milling. In the course of profilometric analysis, all bars were examined in three critical Regions of Interest (ROI): Transmucosal, labial, basal. Sa and Ra values of each construction were determined. To evaluate the necessary refinishing time eight dental technicians macroscopically evaluated the bars by performing a subjective visual inspection. Kruskal-Wallis H-tests and Tukey and Kramer's post hoc tests were applied to detect differences between the samples.


After profilometric examination, three specimens (Dentsply Sirona: ZDC; Straumann: ZST; CAMLOG: ZCC) demonstrated surface roughness values in the biological acceptable range (Sa 0.2-0.4 μm) in the transmucosal region and provided optimal conditions for a reliable soft tissue adaptation. The Ra measurements revealed values beyond the acceptable threshold in the transmucosal region for three bars (Straumann: ZST; Dentsply Sirona: ZDC; Amann Girrbach: LAC). Four bars (LAC: Amann Girrbach; ZBC: BEGO; Datron: LDC & LDT; Zirkonzahn: ZZC) needed undesirable extensive manual rework. The evaluation of quality and time for manual post-processing by dental technicians confirmed the measurement-based ranking of the bars.


It is desirable to define a clear roughness threshold for the clinical acceptance of transmucosal CAD/CAM generated surfaces. Clinical studies with profilometric data could help to further improve the surface quality of CAD/CAM milled bars and reduce the need for manual reworking time and effort.

Keywords: CAD/CAM, Implant-supported bars, Profilometry, Roughness, Surface, Edentulous jaw.

Article Information

Identifiers and Pagination:

Year: 2019
Volume: 13
First Page: 316
Last Page: 326
Publisher Id: TODENTJ-13-316
DOI: 10.2174/1874210601913010316

Article History:

Received Date: 20/04/2019
Revision Received Date: 17/06/2019
Acceptance Date: 04/07/2019
Electronic publication date: 30/08/2019
Collection year: 2019

© 2019 Gehrke et al.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: ( This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at Private Practice for Oral Surgery, Ludwigshafen, Bismarckstrasse 27, Germany / Department of Postgraduate Education, Johann Wolfgang Goethe-University, Frankfurt, Germany;
Tel: +49-621-68124456‬; Fax: +49-621-68124469;

Track Your Manuscript:


"Thank you for your magnificent and marvelous support throughout the publication stages. I would like to endorse my experience with you as a Junior Researcher and a recent graduate of the Dental school. Once again Thank you for your Great Help and Guidance throughout the stages of Publication. You guys are a great team and I am proud to be a Young Bentham author."

Asra Sabir Hussain
The University of Edinburgh Business School, UK

"My experience with Bentham Open was a valuable one because the quality of the services and analysis of my paper contributed in improving what we intended to convey to the readers."

José Ricardo Kina
Department of Surgery and Integrated Clinic,
Araçatuba School of Dentistry, São Paulo State University

"The Publication Manager was very cooperative and replied my mails and guided me without any delays; however the reviewing process was too long."

Mahtab Memarpour
Prevention of Oral and Dental Disease Research Center,
Department of Pediatric Dentistry, School of Dentistry,
Shiraz University of Medical Sciences, Shiraz,

Browse Contents

Webmaster Contact:
Copyright © 2020 Bentham Open