Influence of Third Molars on the Availability of Interradicular Spaces for Miniscrew Implant Placement
The purpose of this study was to assess the influence of the third molars on the availability of interradicular spaces for miniscrew implant placement in the posterior areas of the maxilla and mandible. Panoramic radiographs of 60 subjects (mean age, 18.1±3.1 years) were examined to assess the presence of the third molars. A total of 240 sites were observed. The presence of third molars was observed at 195 sites. Periapical radiographs, made using the paralleling technique, of posterior sites in the maxilla and mandible were examined. For each interradicular site, the interradicular area was measured. The Mann-Whitney U test was used to compare the mean interradicular area values between the groups in which third molars were present or absent. In the maxillary arch, the presence of third molars significantly reduced the amount of the interradicular space only between the first and second molars (17.2±0.5 mm2 ), compared to the absence of third molars (20.8± 1.2 mm2 ). In the mandibular arch, the presence of third molars did not affect the amount of interradicular space. The presence of the maxillary, but not the mandibular, third molars played an important role in the availability of interradicular spaces between the first and second molars.
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