Pathologic status and changes in mandibular third molar position during orthodontic treatment

The purpose of this study was to evaluate the changes in mandibular third molar (M3) position and pathologic status associated with M3 in the cases orthodontically treated.

This study was carried out on a total of 76 subjects, 42 males and 34 females ranging in age from 18 to 23 years. Thirty of them were treated without extractions (non-extraction group), 26 were treated with the extraction of four first premolars (extraction group), and 20 did not receive orthodontic treatment (control group). Positional changes of third molars and pathologic status associated with M3s in the cases treated orthodontically were evaluated radiographically and clinically. Data were analyzed with parametric and non-parametric tests.

It was clinically observed that 18% of third molars in the non-extraction group and 15% of those in the extraction group erupted in normal position; 83% of third molars in both groups erupted partially in a mesioangular position. However, it was determined that 43% of the teeth that partially erupted developed pericoronitis and 4% had dental caries. It was determined radiographically that there was insufficient space for most of the M3s to erupt in the orthodontically treated cases and the angulations of these teeth were not sufficiently improved.

In this study, it was determined that 83% of the M3s in orthodontically treated cases partially erupted in a mesioangular position and 43% of these teeth were associated with pericoronitis.