Evaluation of Angular Changes of Canine in En Masse Retraction of Maxillary Anterior Teeth Using Power Arm and Titanium Mini-Implant - A Split Mouth Randomised Control Study

BACKGROUND This study was conducted to determine angular changes of maxillary canine in en masse retraction of anterior teeth in a new modified power arm with a conventional intraoral anchorage unit compared to a mini-implant anchorage in the first premolar extraction case. We wanted to compare angular changes of maxillary canine between modified conventional anchorage with a power arm and titanium mini-implant anchorage in en masse retraction. METHODS A total of 15 participants requiring maxillary first premolar extraction was selected for this study. In each participant, the en mass retraction was carried out with miniimplants on one side & modified conventional anchorage with a power arm on the other side. The choice of mode of retraction on the right and the left side was done based on the coin flip method. Angular position of the maxillary canine was evaluated on orthopantomogram (OPG) & diagnostic cast. RESULTS A mean disto-palatal rotation observed post retraction was of 9° on the conventional anchorage side & 9.86° on the mini-implant anchorage side. A mean difference in maxillary canine angulations post retraction was 1.13° on the conventional anchorage side and 0.93° on the mini-implant side. An increase in angle suggested the tipping of canine teeth. The difference was very small which was not statistically & clinically significant. CONCLUSIONS There was no difference in the type of tooth movement during retraction by miniimplant and power arm suggesting minimal variation in teeth movement in the anterior region. So, the choice mainly depends on the type of the anchorage required in the given clinical situation. KEY WORDS Anchorage, Mini-Implant, Power Arm, Type of Tooth Movement