A comparative study of initial changes in pulpal blood flow between conventional and self-ligating fixed orthodontic brackets during leveling and alignment stage

Objectives To evaluate and compare the initial changes in pulpal blood flow (PBF) between conventional and self-ligating fixed orthodontic brackets during leveling and alignment stage using 0.016 x 0.022 NiTi as alignment archwire. Materials and methods Twenty-two patients (16 females and 6 males) aged 19.00 +/- 2.53 years who presented with mild lower arch crowding were selected to participate in the study. A split mouth study design was applied for each patient. The intervention (self-ligating brackets) was randomly allocated to the right or left side of the patient using the permuted random block size of 2 with 1:1 allocation ratio. Two different fixed appliance brackets were used in the lower arch (self-ligating brackets on one side and conventional brackets on the other side of the same patients. Two alignment archwires; 0.016 '' NiTi and 0.016 x 0.022 '' NiTi were used in this study. PBF was measured for the lower right and left sides using laser Doppler flowmetry at different time intervals (20 min, 24 h, 72 h, 1 week, and 1 month) Results PBF started to decrease 20 min after insertion of both archwires using both types of brackets. Maximum decrease was reached after 72 h of archwire insertion. After 1 week of force application, PBF started to increase to restore its original values after 1 month. Differences between the 2 groups were not significant (P> 0.05). Conclusions In both treatment groups, PBF reduced within 48 h. PBF started to increase after 1 week until it reached its original values after 1 month. Changes in PBF at the measured time intervals in the two groups were similar.

Automated summary

This study compared the initial changes in pulpal blood flow between conventional and self-ligating fixed orthodontic brackets. It was found that PBF started to decrease after 20 minutes of archwire insertion, reached the maximum decrease after 72 hours, and returned to baseline values after 1 month in both groups.