Histological, histomorphometrical, and radiological evaluation of an experimental implant design with a high insertion torque.
OBJECTIVE
The aim of this study was to compare bone behaviour around an experimental implant design with a high insertion torque with the Astra-Tech implant (control).


METHODS
In ten 18-month-old male minipigs, the last premolars and first molars were extracted to provide space for two implants in each quadrant. A first set of 40 implants were placed 3 months after the extraction and 40 additional implants were installed another 2 months later. The animals were sacrificed 3 months after the first implant installation so that half of the implants had healed for 1 month and the other half for 3 months. Radiological evaluation was performed at baseline, 1 month, 2 months, and 3 months after implant installation. Bone defect depth and area, bone level changes, bone-to-implant contact density, and peri-implant bone fraction were measured histomorphometrically.


RESULTS
Radiological analyses revealed a significantly higher bone loss around the experimental implants. Histomorphometric analyses confirmed significantly more bone loss, larger marginal bone defects, and a lower overall peri-implant bone fraction around the experimental implants.


CONCLUSIONS
The experimental implant design caused significantly more peri-implant bone loss compared with the control implant. As strain gauge measurements indicate excessive marginal strains around the experimental implants, osseocompression might have played a role in the observed marginal bone loss.
Department of Prosthetic Dentistry, BIOMAT Research Group, Katholieke Universiteit Leuven, Leuven, Belgium. joke.duyck@med.kuleuven.be
Joke
J
Duyck
Livía
L
Corpas
Stephanie
S
Vermeiren
Toru
T
Ogawa
Marc
M
Quirynen
Katleen
K
Vandamme
Reinhilde
R
Jacobs
Ignace
I
Naert
D000539:Alveolar Process / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D000818:Animals; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D003799:Dental Stress Analysis; D020007:Implants, Experimental; D008297:Male; D016348:Osseointegration; D011859:Radiography; D013552:Swine; D013556:Swine, Miniature; D019415:Torque
D015921:Dental Implants