Pongstorn Putongkam. Evaluation of Cathepsin B levels in GCF during tooth movement in orthodontic patients . Master's Degree(Orthodontics). Mahidol University. : Mahidol University, 2006.
Evaluation of Cathepsin B levels in GCF during tooth movement in orthodontic patients
Abstract:
The purposes of this study were to investigate the expression level of Cathepsin B in GCF during orthodontic tooth movement, and to compare the difference of expression levels of this enzyme generated by different magnitudes of orthodontic forces. Twenty maxillary canines from ten orthodontic patients (two males, mean age 20.88 ± 1.24 years and eight females, mean age 20.17 ± 1.58 years) were retracted by continuous forces of 50 g. and 150 g., while one of the mandibular canines, either side, was used as a control. All participants had to maintain their oral hygiene in good status during 2 months of the experimental period.
The GCF was collected from the distal site of each tooth. The absorbed fluid volume and total protein volumes were then measured. The Cathepsin B levels from GCF were determined by Western blot analysis. Enzyme activity assay was performed by using Z-Arg-Arg-AMC as substrate. Accordingly, the Visual Analog Scale (VAS) representing patients’ pain was recorded and analyzed. The distance derived from each experimental tooth movement was measured from each study model at before and 2 months after activation.
The results show that the mean GCF volumes were increased mostly at 24 hours in all groups, but significant differences were not detected. Mean total protein concentrations of all samples showed no significant differences when compared between groups. Western blot analysis of the collected GCF samples confirmed that there was Cathepsin B in detectable level. For the 50 g. continuous force, Cathepsin B activity showed a significant increase at 24 hours compared with before activation (p<0.05). For 150 g. continuous force, Cathepsin B activity showed the delay increasing at 1 week with no significant difference. However, the 50 g. force tended to produce more distance of tooth movement compared with 150 g. The mean VAS scores represented patients’ pain from 150 g. force seemed to be higher than 50 g. at 24 hours but a significant difference was not found.
In conclusion, Cathepsin B can be used as a marker in orthodontic tooth movement. The very light continuous orthodontic force could produce the significant increase of this enzyme activity and give enough effectiveness to produce tooth movement similar to the higher force.