Author/Editor     Sprogar, Š; Coer, A; Drevenšek, G; Drevenšek, M
Title     Ortodontski premik zoba in pregrajevanje kosti
Translated title     Orthodontic tooth movement and bone remodelling
Type     članek
Source     Zobozdrav Vestn
Vol. and No.     Letnik 62, št. 4-5
Publication year     2007
Volume     str. 129-36
Language     slo
Abstract     Background: Tooth movement is the consequence of bone remodelling of periodontal tissues. Two major cell types, osteoblasts and osteoclasts, are involved in this process. The aim of our study was to determine the percentage of trabecular bone and the number of osteoclasts and osteoblasts during orthodontic tooth movement (OTM) compared to physiological tooth movement, and to establish differences in the number of the two types of cells between the tension side and the pressure side during OTM in rats. Material and methods: In the test group of animals (n=7), a closed coil spring was applied between the upper first left molar and both incisors. No springs were applied in the control group (n=7). Distances between the above-mentioned teeth were measured with a digitronic calliper on days 0, 7, 14, 21, 28, 35 and 42. After 42 days, the animals were sacrificed and the left side of the upper jaw with all three molars and periodontal ligament was prepared for histological and histomorphometrical analysis. The percentage of trabecular bone was determined at 10fold magnification and the percentage of alveolar bone covered with osteoblasts and osteoclasts at 40.fold magnification. Results: The distance between the studied teeth significantly decreased in the test group compared to the control group (p<0.001). The percentage of trabecular bone was significantly lower (p<0.05), and the percentage of alveolar bone covered with osteoclasts was significantly higher in the test group compared to the control group (p<0.001). Conclusions: Compared to physiological movement, OTM caused a decrease in the percentage of trabecular bone and an increase in the percentage of osteoclasts, while the percentage of osteoblasts remained unchanged. During OTM, osteoclasts were more active than osteoblasts; both types of cells were evenly distributed between the pressure side and the tension side.
Descriptors     TOOTH MOVEMENT
DENTAL ARCH
MOLAR
OSTEOBLASTS
OSTEOCLASTS
RATS, WISTAR