title: Radiographic findings on 3rd molars removed in 20-year-old men.
abstract: In this study we assess radiographic findings characteristic of mandibular 3rd molars that had required either routine or surgical extraction. X-ray findings relating to acute pericoronitis were also examined. The material was collected by investigating patient records and rotational panoramic radiographs of 20-year-old Finnish male conscripts (n = 738) treated during military service because of 3rd-molar-related problems. The follicle around the crown of mandibular 3rd molars with acute pericoronitis was enlarged in 19% of cases and in 13% of chronic symptom-free pericoronitis cases (not statistically significant difference). Mandibular 3rd molars extracted surgically were more often mesially inclined than those extracted routinely (61% vs. 23%; P < 0.001), partially or totally intrabony impacted (92% vs. 66%; P < 0.001) and deep situated (on average 4.2 mm vs. 2.5 mm under the occlusal plane). Surgical extraction was also associated with the roots completely developed [92% vs. 84% of the teeth routinely extracted, odds ratio (OR) 2.6, 95% confidence interval (CI) 1.2-5.5] and with the absence of radiographic pericoronitis [around 27% vs. 39% of the teeth routinely extracted (OR 0.5, 95% CI 0.3-0.8)]. In 86% of cases the space between 2nd molar and ramus of the mandible was narrower than the 3rd molar extracted surgically, whereas this was 62% in routine extraction cases (P < 0.001). We conclude that there are some typical 3rd-molar findings in rotational panoramic radiographs that show a need for surgical extraction.
authors.affiliation: Department of Oral and Maxillofacial Diseases, Mikkeli Central Hospital, Mikkeli, Finland. ari.rajasuo@esshp.fi
authors.forename: Ari
authors.initials: A
authors.lastname: Rajasuo
authors.forename: Jaakko
authors.initials: J
authors.lastname: Peltola
authors.forename: Irja
authors.initials: I
authors.lastname: Ventä
authors.forename: Heikki
authors.initials: H
authors.lastname: Murtomaa
mesh_terms: D000328:Adult; D016009:Chi-Square Distribution; D002908:Chronic Disease; D016001:Confidence Intervals; D003795:Dental Sac / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging / Q000601:surgery; D008889:Military Personnel; D008964:Molar, Third / Q000000981:diagnostic imaging* / Q000601:surgery; D016017:Odds Ratio; D009805:Odontogenesis / Q000502:physiology; D010497:Pericoronitis / Q000000981:diagnostic imaging; D011862:Radiography, Panoramic; D012189:Retrospective Studies; D019228:Tooth Crown / Q000000981:diagnostic imaging; D014081:Tooth Extraction; D014092:Tooth Root / Q000000981:diagnostic imaging; D014095:Tooth, Impacted / Q000000981:diagnostic imaging / Q000601:surgery