Download AMOUNT OF TOOTH MOVEMENT GENERATED BY TWO

AMOUNT OF TOOTH MOVEMENT GENERATED BY TWO
DIFFERENT ORTHODONTIC FORCE APPLICATIONS
Nalinee Srianantanon1,*, Supatchai Boonpratham2,#, Suwannee
Luppanapornlarp3, Rudee Surarit4
1
Master of Science (Orthodontics), Department of Orthodontics, Faculty of Dentistry,
Mahidol University, Thailand
2,3
Department of Orthodontics, Faculty of Dentistry, Mahidol University, Thailand
4
Department of Oral Biology, Faculty of Dentistry, Mahidol University, Thailand
*e-mail: [email protected], #e-mail: [email protected]
Abstract
Background: Orthodontic tooth movement occurs as a result of bone and surrounding tissue
remodeling. Many researchers have been studied in animals and human to identify the
optimal magnitude or range of force for orthodontic tooth movement. Previous findings in
human showed the proper forces for tooth movement had range from 18 g force to 1515 g
force. The optimal force that can be recommended for clinical use is still controversy. This
study aimed to compare the effectiveness of 50g and 150g orthodontic forces by measuring
the amount of tooth movement after 2 months of canine retraction.
Materials and methods/ Study designs: Five female patients, aged 18-30 years old who had
four first bicuspid extraction were participated in this study. The upper canines were retracted
with continuous 50g and 150g forces using NiTi coil springs on segmented archwires using a
miniscrew implant as an anchorage. A cone beam computed topographic (CBCT) images
were taken before force application and 2 months after canine retraction. The two images
from cone beam computed tomography or CBCT were superimposed by using all posterior
teeth as reference points. The distance between distal most of the crown of the two
superimposed canines was used to determine the amount of tooth movement.
Results: A paired t-test was used for comparing the amount of canine movement between the
50g and 150g force. No significant difference in the amount of tooth movement was found
between two different magnitudes of force at two months (p < 0.05).
Conclusions: Both 50g and 150g forces could effectively induce tooth movement in a similar
manner.
Keywords: tooth movement, optimal force, CBCT