Methods: The measurements were made at mesial site and distal site of the 31 retracted canines in 17 orthodontic patients (3 males and 14 females), 21-26 years of age who were patients in orthodontic department of Srinakarinwirot University. The blood flow rates were determined in the attached gingival on both site, mesial site was tension site and distal site was pressure sites. The Laser Doppler Flowmetry recordings were performed before applying 300 gm elastomeric force and immediately applying force. It was continuously observed on day 1, 3, 7, 14, 21 and 28.
Results: There were significantly increasing of GBF after applied force on both sites (P<0.05). A peak of GBF were observed on day 1 and returned nearly to the baseline by day 21. During one month, the elastomeric force reduced by 2/3 of the beginning.
Conclusions: The results of this study presented that the increasing of GBF in the first day showed the highest degree of gingival inflammation. During one month of the orthodontic treatment, there was more inflammation on the pressure site than on the tension site. However, the healing could return by day 21.