Relation between insertion torque and bone-implant contact percentage: an artificial bone study.
OBJECTIVE
The purpose of this study was to determine the correlation between the peak insertion torque value (ITV) of a dental implant and the bone-implant contact percentage (BIC%).


METHODS
Dental implants were inserted into specimens comprising a 2-mm-thick artificial cortical shell representing cortical bone and artificial foam bone representing cancellous bone with four densities (groups 1 to 4--0.32, 0.20, 0.16, and 0.12 g/cm(3)). Each specimen with an inserted implant was subjected to micro-computed tomography (micro-CT) scanning, from which the 3D BIC% values were calculated. Pearson's correlation coefficients (r) between the ITV and BIC% were calculated.


RESULTS
The ITVs in groups 1 to 4 were 56.2 ± 4.6 (mean±standard deviation), 45.6 ± 0.9, 43.3 ± 4.3, and 38.5 ± 3.4 N cm, respectively, and the corresponding BIC% values were 41.5 ± 0.5%, 39.0 ± 1.0%, 30.8 ± 1.1%, and 26.2 ± 1.6%. Pearson's correlation coefficient between the ITV and BIC% was r = 0.797 (P < 0.0001).


CONCLUSIONS
The initial implant stability, quantified as the ITV, was strongly positively correlated with the 3D BIC% obtained from micro-CT images.


CONCLUSIONS
The ITV of a dental implant can be used to predict the initial BIC%; this information may provide the clinician with important information on the optimal loading time.
Institute of Biomedical Engineering, National Cheng Kung University, Tainan 701, Taiwan.
Cheng
C
Liu
Ming-Tzu
MT
Tsai
Heng-Li
HL
Huang
Michael Yuan-Chien
MY
Chen
Jui-Ting
JT
Hsu
Kuo-Chih
KC
Su
Chih-Han
CH
Chang
Aaron Yu-Jen
AY
Wu
D001696:Biomechanical Phenomena; D015519:Bone Density / Q000502:physiology; D001842:Bone and Bones / Q000033:anatomy & histology*; D003758:Dental Implantation, Endosseous / Q000379:methods; D015921:Dental Implants; D017268:Dental Prosthesis Retention; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008953:Models, Anatomic; D016062:Porosity; D013499:Surface Properties; D019415:Torque; D055114:X-Ray Microtomography / Q000379:methods
D015921:Dental Implants