Biomechanical and histomorphometric characterizations of osseointegration during mini-screw healing in rabbit tibiae.
OBJECTIVE
To evaluate effects of different healing times on integration of titanium mini-screws and bones under unloaded conditions.


METHODS
Biomechanical stability measurements and histomorphometric observations were performed in a rabbit tibia model after different healing times: 0 (immediate) and 1, 2, 4, and 8 weeks.


RESULTS
Biomechanical stability and both maximum torque and maximum pullout load increased with healing time but increased significantly only after 4 weeks. Maximum torque and maximum pullout load both significantly correlated with healing time and with each other. Similarly, histomorphometric analyses showed that new bone formation increased with healing time but increased dramatically only after 4 weeks. The data may provide guidance for determining optimal implant plans in clinical practice.


CONCLUSIONS
Mini-screw healing is a continuous process, and week 4 is a critical time point in this process.
Department of Orthodontics, Capital Medical University, School of Stomatology, Chongwen district, Beijing, Beijing 100050, China. crystalwupaper@gmail.com
Jing
J
Wu
Yu-Xing
YX
Bai
Bang-Kang
BK
Wang
D000818:Animals; D001696:Biomechanical Phenomena; D001863:Bone Screws; D003094:Collagen / Q000648:ultrastructure; D003764:Dental Materials; D005347:Fibroblasts / Q000473:pathology; D006097:Granulation Tissue / Q000473:pathology; D008264:Macrophages / Q000473:pathology; D008297:Male; D008855:Microscopy, Electron, Scanning; D023421:Models, Animal; D016348:Osseointegration / Q000502:physiology*; D010006:Osteoblasts / Q000473:pathology; D010012:Osteogenesis / Q000502:physiology; D011817:Rabbits; D011897:Random Allocation; D013314:Stress, Mechanical; D013977:Tibia / Q000473:pathology / Q000502:physiology*; D013997:Time Factors; D014025:Titanium; D019415:Torque; D014945:Wound Healing / Q000502:physiology
D003764:Dental Materials; D003094:Collagen; D014025:Titanium