To the top

Page Manager: Webmaster
Last update: 9/11/2012 3:13 PM

Tell a friend about this page
Print version

A comparison between cutt… - University of Gothenburg, Sweden Till startsida
To content Read more about how we use cookies on

A comparison between cutting torque and resonance frequency measurements of maxillary implants. A 20-month clinical study.

Journal article
Authors Bertil Friberg
Lars Sennerby
N Meredith
Ulf Lekholm
Published in International journal of oral and maxillofacial surgery
Volume 28
Issue 4
Pages 297-303
ISSN 0901-5027
Publication year 1999
Published at Institute of Odontology
Institute of Surgical Sciences, Department of Biomaterials
Pages 297-303
Language en
Keywords Aged, Bone Density, Dental Implantation, Endosseous, statistics & numerical data, Dental Prosthesis, Implant-Supported, statistics & numerical data, Female, Humans, Jaw, Edentulous, radiography, surgery, Male, Mandible, radiography, surgery, Middle Aged, Statistics, Nonparametric, Torque
Subject categories Surgical research


Oral implant treatment ad modum Brånemark was undertaken in nine patients with edentulous maxillae. Cutting torque measurements and resonance frequency analyses (RFA) were conducted at implant placement and the corresponding values were subjected to correlation analyses. The implants were also evaluated with RFA at abutment connection and at one-year follow-up in order to identify possible changes in implant stability. A total of 61 implants were inserted, of which 49 were of the Mk II self-tapping type. Two implants were lost during the study period. The cumulative torque was presented as a mean value for the upper/crestal, the middle and the lower/apical third of the implant site respectively, as well as an overall value for the whole site. The highest correlation (r = 0.84, P<0.05) was found when comparing the mean torque values of the upper/crestal portion with the resonance frequency values at implant placement. The Mk II implant sites were divided into three groups based on the values of the cutting torque, i.e. soft (group 1), medium (group 2) and dense bone (group 3). The mean value of each group was plotted against the corresponding mean value of resonance frequency measured at implant insertion. Statistical analysis showed significant differences in resonance frequency at implant insertion between groups 1 and 2 (P = 0.047) and between groups 1 and 3 (P = 0.002). When repeating the resonance frequency analyses at second stage surgery and at one-year follow-up, no significant differences were detected between any of the groups. It was shown that the stability of implants placed in softer bone seemed to "catch up" over time with more dense bone sites.

Page Manager: Webmaster|Last update: 9/11/2012

The University of Gothenburg uses cookies to provide you with the best possible user experience. By continuing on this website, you approve of our use of cookies.  What are cookies?