Changes in Third Molar Position after En-masse Retraction in Bimaxillary Dentoalveolar Protrusion Cases

Introduction: This study aimed to evaluate the changes in the space available for eruption of third molars as well as their angulation after treatment of bimaxillary dentoalveolar protrusion cases with 1st premolars extractions implementing maximum anchorage.
Methods: The sample of the current study comprised 41 adult females (mean age of 20.8 ±2.03) having bimaxillary dentoalveolar protrusion. All participants received the same treatment protocol where TADs were used for direct maximum anchorage followed by 1st premolars extraction and en-masse retraction of the anterior teeth over 0.019” × 0.025” main working archwire. Third molar angulation and its available space pre-and post-treatment was assessed via panoramic radiographs using IC Measure 2.0.0.161 software. Paired t tests were used for intragroup comparison between pre and post-treatment data.
Results: Analysis of the linear variables demonstrated a non-statistically significant difference between the 2 groups for all third molar eruption spaces. The mean differences in the third molar angulation between the pretreatment and posttreatment values revealed a decrease in the angulation yet these changes were non-significant.
Conclusion: This study suggests that orthodontic treatment comprising extraction of first premolars and en-masse retraction utilizing maximum anchorage doesn’t lead to a significant improvement in the angulation nor the space available for third molar eruption by the end of treatment.