Clinical Oral Investigations

, Volume 23, Issue 2, pp 763–770 | Cite as

Locator® versus ceramic/electroplated double-crown attachments: a prospective study on the intraindividual comparison of implant-supported mandibular prostheses

  • Silvia BrandtEmail author
  • Jan Brandt
  • Ali-Reza Ketabi
  • Hans-Christoph Lauer
  • Anna Kunzmann
Original Article



Implant-supported overdentures are an established dental treatment mode. The aim of this prospective study was and interindividual comparison of patient satisfaction with restorations retained by a prefabricated and thus inexpensive attachment system (Locator®) or with a technologically complex and thus expensive attachment system (ceramic/electroplated double crowns) with similar retentive performance.

Materials and methods

Twelve patients received a Locator and a double-crown prosthesis in a crossover study for test periods of 3 months each. The main target parameter was the patient’s final decision in favor of one of the two prosthesis types.


After completing both test phases, seven patients opted for the Locator prosthesis and five patients opted for the double-crown prosthesis.


Given the predominant lack of statistically significant differences, the two types of prostheses can be described as equivalent. A recommendation in favor of the Locator prosthesis can be motivated by its lower cost.

Clinical relevance

The results of the study show that the more cost-effective variant was comparable to the more expensive double-crown prosthesis under the conditions prevailing in the study. Depending on the indication, this may influence the decision-making process in daily clinical practice and support the clinician’s patient information and consultation efforts.


Locator attachment Double-crown attachment Ceramic/electroplated double crowns Edentulous patient Overdenture Coverdenture Dental implants 



We would like to thank Dentsply Implants (Mannheim, Germany) for supporting this clinical study.


The work was supported by Dentsply Implants (Mannheim, Germany).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interests.

Ethical approval

As the examinations were conducted with human participants, an approval was commissioned and issued by the Ethics Commission of the Medical Department at the Goethe University of Frankfurt with transaction number 117/11 before the beginning of the study. All procedures performed in the study were in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Silvia Brandt
    • 1
    • 2
    Email author
  • Jan Brandt
    • 1
    • 2
  • Ali-Reza Ketabi
    • 3
  • Hans-Christoph Lauer
    • 1
    • 2
  • Anna Kunzmann
    • 1
    • 2
  1. 1.Department of Prosthodontics, Hospital for Dental, Oral and Orthodontic Medicine (Carolinum)Johann Wolfgang Goethe University Frankfurt am MainFrankfurtGermany
  2. 2.Poliklinik für Zahnärztliche Prothetik, ZZMK CarolinumJohann Wolfgang Goethe – Universität Frankfurt am MainFrankfurtGermany
  3. 3.StuttgartGermany

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