The application of resonance frequency measurements to study the stability of titanium implants during healing in the rabbit tibia

Abstract

The aim of this investigation was to measure the resonance frequency of a number of implants placed in the rabbit tibia at insertion and at predetermined periods thereafter and to correlate the results with histomorphometric measurements made when the animals were sacrificed. Ten mature New Zealand White rabbits were used in the study. Two c.p. threaded titanium implants were placed in the right tibia of each animal. Resonance frequency measurements were made by screwing a small transducer onto a standard abutment mounted on each fixture. Measurements were repeated with the transducer oriented perpendicular and parallel to the long axis of the tibia for all proximal implants 14 and 28 days after placement and in 6 implants additionally at 42, 56, 93, 122 and 168 days after which all animals were sacrificed. Histomorphometric analysis comprised 2 parts; measurement of bone-implant contact area and height. A significant increase in resonance frequency was observed after 14 (405 Hz, +/- 234 Hz) and 28 (658 Hz, +/- 332 Hz) days. The increase in resonance frequency levelled after approximately 40 days and little further change was observed. The variation in bone-implant contact area was relatively small (1.8-4.9 mm2) and the range of bone-implant contact heights was also narrow (-1.5 (-)+ 1.5 mm). Values for resonance frequencies plotted against contact area and height were grouped around 10 kHz. In conclusion, it was shown that resonance frequency measurements can be made at placement and during healing in vivo and changes may be related to the increase in stiffness of an implant in the surrounding tissues.

Long-term follow-up of dental single implants under immediate orthodontic load

“…29 In addition, the RFA showed the same sensitivity as the manual test. 30 In an extensive systematic review on reinforcement of anchorage during orthodontic treatment using implants and other surgical methods, Skeggs et al 1 reported that evidence regarding the favorable outcomes of immediate orthodontic load in osseointegrated implants is reasonable, although they recommended further studies in adult human patients. The present RCT with 13 patients and 20 osseointegrated implants contributed to preliminary data about this issue in human subjects instead of animal or laboratory studies, 2 and it compared immediate vs delayed orthodontic and prosthetic load in single mandibular implants.…”

Stability of dental implants after irradiation with an 830-nm low-level laser: a double-blind randomized clinical study

“…The importance of primary stability in implant placement for long-term success is well known in the literature. Clinical methods like implant percussion, radiography, insertion torque, and manual reverse torque, are questionable methods regarding their effectiveness for measuring the quality of implant osseointegration [18]. Invasive biomechanical tests such as removal torque and histomorphometric analysis measurements can provide important information regarding implant rigidity in the bone during a certain period of the osseointegration process and can accurately assess morphological changes at the boneimplant interface, respectively; however, these methods demand sacrifice of the implant and preclude clinical follow-up afterwards, which is unfeasible for monitoring clinical changes at the bone-implant interface [19,20].…”

Application of the finite element method in dental implant research

“…It has long been a recognized need among dental professionals involved in dental implant therapy. 55 The measurement is taken with a transducer screwed onto the implant, the piezo elements of which are caused to oscillate. The device records the resonance frequency produced from the implant-bone interface which is displayed graphically.…”