Odontologa

´ ¨chter
Andre Bu
Dirk Wiechmann
Stefan Koerdt
Hans Peter Wiesmann
Josef Piffko
Ulrich Meyer

Authors’ affiliations:
´ ¨chter, Stefan Koerdt, Hans Peter
Andre Bu
Wiesmann, Josef Piffko, Ulrich Meyer, Department
of Cranio-Maxillofacial Surgery, University of
Munster, Munster, Germany
¨
¨
Dirk Wiechmann, Orthodontic Department,
Medical School Hanover, Germany
Correspondence to:
´¨chter
Dr Andre Bu
Department of Cranio-Maxillofacial Surgery
University of Munster
¨
Waldeyerstrae 30
D-48129 Munster
¨
Germany
Tel.: þ 49 251 834 7013
Fax: þ 49 251 834 7020
e-mail: Buchtea@uni-muenster.de

Load-related implant reaction of miniimplants used for orthodontic anchorage

Key words: anchorage, implant stability, orthodontic tooth movement, osseointegration
Abstract:The purpose of this study was to determine the clinical and biomechanical
outcome of two different titanium mini-implant systems activated with different load
regimens. A total of 200 mini-implants (102 Abso Anchors and 98 Dual Tops) were placed
¨
in the mandible of eight Gottinger minipigs. Two implants each were immediately loaded
in opposite direction by various forces (100, 300 or 500 cN)through tension coils.
Additionally, three different distances between the neck of the implant and the bone rim
(1, 2 and 3 mm) were used. The different load protocols were chosen to evaluate the loadrelated implant performance. The load was provided by superelastic tension coils, which are
known to develop a virtually constant force. Non-loaded implants were used as a reference.
Following anexperimental loading period of 22 and 70 days half of the minipigs were
sacrificed, and implant containing bone specimens evaluated for clinical performance and
implant stability. Implant loosing was found to be statistically dependent on the tip
moment (TM) at the bone rim. Clinical implant loosing were only present when load
exceeded 900 cN mm. No movement of implants through the bone wasfound in the
experimental groups, for any applied loads. Over the two experimental periods the nonloaded implants of one type of implant had a higher stability than those of the loaded
implants. Dual Tops implants revealed a slightly higher removal torque compared with
Abso Anchors implants. Based on the results of this study, immediate loading of miniimplants can be performed without loss ofstability when the load-related biomechanics do
not exceed an upper limit of TM at the bone rim.

Date:
Accepted 29 September 2004
To cite this article:
Buchter A, Wiechmann D, Koerdt S, Wiesmann HP,
¨
Piffko J, Meyer U. Load-related implant reaction of
mini-implants used for orthodontic anchorage.
Clin. Oral Impl. Res. 16, 2005; 473–479
doi: 10.1111/j.1600-0501.2005.01149.x

Copyright rBlackwell Munksgaard 2005

The number of adult patients requiring
orthodontic therapy has undergone a
marked increase in recent decades (Bauer
& Diedrich 1990). However adults frequently present pathologic findings like
periodontal and endodontic diseases, dysfunction of the mandibular joint, and early
loss of teeth (Diedrich 2000). As the temporary use of the native dentition fororthodontic anchorage is frequently limited, and
extraoral appliances are rejected for aesthetic reasons, an alternative approach
based on stable and cooperation-independent anchorage is needed (Fritz et al. 2003).

Numerous studies have shown that conventional osseointegrated implants are suitable for orthodontic loading and offer
stable anchorage for orthodontic purposes
(Gray et al. 1983; Robertset al. 1994;
¨
Odmann et al. 1988; Smalley et al. 1988;
Wehrbein & Diedrich 1993). Wehrbein &
Diedrich (1993) moreover reported that the
application of orthodontic forces positively
affects the peri-implant bone situation of
osseointegrated implants. In additional studies, Wehrbein (1994) and Wehrbein et al.
(1999) evaluated the quantity of mineralized bone in the vicinity of the implant...