Eruption disturbances of the first and second permanent molars: results of treatment in 43 cases.

Impaction or retention of first and second permanent molars is an uncommon condition with diverse therapeutic approaches. To ascertain the success rate of different treatment possibilities, a retrospective study was made of 25 patients with a total of 43 permanent molars with eruption disturbances. In most cases, the nonerupted teeth were mandibular second molars (65%), followed by maxillary second molars (21%). Their position, degree of impaction (inclusion), clinical features, repercussion on the neighboring teeth, type of treatment, and outcome were evaluated. Infraocclusion was often associated with malposition of neighboring teeth, as well as extrusion and infraocclusion of opposing teeth. Due mostly to a delay in the diagnosis of the condition, an acceptable final position of the nonerupted molar was obtained in only 8 of 13 conservatively treated second molars. In order to prevent this situation, radiographic examination (ideally during the early mixed dentition period) and early diagnosis of eruption disturbances of permanent first and second molars are recommended, particularly when considering that these anomalies are associated with a high rate of occlusal disturbances that may require orthodontic correction.