Incidence of impacted teeth requiring fenestration, traction, and orthodontic treatment in Japan

ABSTRACT Purpose This survey aimed to estimate the incidence and severity of impacted teeth indicated for fenestration or fenestration and traction in patients who visited several dental institutions nationwide in Japan from 1 April 2015 to 31 March 2016. Materials and Methods An online survey was conducted, and 236 dental institutions responded, with 176 reporting their experience with cases of impacted teeth indicated for fenestration/traction. Results Of the 1,683 cases of impacted teeth indicated for fenestration/traction, 434 (25.8%), 391 (23.2%), and 858 (51.0%) were treated using fenestration alone, fenestration/traction, and fenestration/traction and orthodontic treatment, respectively. Impacted teeth were most prevalent in the anterior maxillary region, especially in the canine region, with 435 (24.0%) and 411 (22.7%) impacted teeth on the right and left quadrants, respectively. The most commonly used diagnostic criteria were the radiographic findings of clear inversion or horizontal impaction showing that spontaneous eruption would be difficult in 123 (37.4%) cases. The most severe cases indicated for fenestration/traction were those with two or more impacted teeth, observed in 279 (56.7%) cases, followed by 174 cases of root resorption of adjacent teeth (35.4%). Root resorption due to impacted teeth was most prevalent in the maxillary left lateral incisors, evident in 65 cases (24.5%). Conclusion This study found that impacted teeth often have serious sequelae such as root resorption of adjacent teeth. Thus, early detection and intervention of impacted teeth, as well as preoperative and postoperative orthodontics to establish a physiologically normal occlusion, are necessary.