[Stability of the miniscrew implant during healing period].
OBJECTIVE
To evaluate the stability of mini-screw implant during different healing periods in the unloaded conditions.


METHODS
Sixty titanium mini-screws were used in this study. A total of 10 New Zealand white rabbits were randomly divided into 5 groups according to different healing periods. The stability was evaluated biomechanically at different time points. One-way ANOVA and correlation analyses were used.


RESULTS
(1) After 4 weeks and 8 weeks of healing, maximal pull-out loads were (179.68 +/- 24.65) N and (212.06 +/- 42.51) N, respectively. The maximal torques were (0.47 +/- 0.13) N.m and (0.61 +/- 0.16) N.m, respectively. (2) Significant difference in maximal torque was found between 4 week and 8 week healing groups. (3) Both reverse torque and pull-out load significantly correlated with healing time.


CONCLUSIONS
Fourth-week is a critical time point in the progress of osseointegration. Within 8 weeks of healing process, the stability of implant was significantly correlated with healing time.
Wu
Jing
J
Department of Orthodontics, Faculty of Stomatology, Capital University of Medical Sciences, Beijing 100050, China.
Bai
Yu-xing
YX
Wang
Bang-kang
BK
Gao
Xiao-hui
XH
D000818:Animals; D001863:Bone Screws; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D003799:Dental Stress Analysis; D008297:Male; D052280:Orthodontic Anchorage Procedures; D016348:Osseointegration / Q000502:physiology*; D011817:Rabbits; D013314:Stress, Mechanical; D013997:Time Factors; D014025:Titanium; D019415:Torque; D014945:Wound Healing / Q000502:physiology
D015921:Dental Implants; D014025:Titanium