Effect of non-erupted 3rd molars on distal roots and supporting structures of approximal teeth. A radiographic survey of 202 cases.
Root resorption of 2nd molars in proximity to non-erupted 3rd molars has been widely reported. The purpose of this study was to determine the prevalence of root resorption in second molars adjacent to non-erupted third molars. Its association to age and gender of the patient, location and inclination of the non-erupted third molar and to distal bone support of the 2nd molars was analyzed. A radiographic survey of 202 periapical radiographs taken in patients with clinically missing third molars was conducted. 3 examiners independently evaluated the radiographs and only those cases where at least 2 observers agreed were included in this report. Statistical analysis was performed on 186 radiographs. Associations were analyzed with the Pearson chi 2 test. Radiographic evidence of root resorption was found in 45 2nd molars (24.2%) of which 12 (6.5%) showed moderate to complete root resorption. Non-erupted tooth apical position and mesio-inclination of 60 degrees or more relative to the distal root of the second molar were significantly associated with root resorption (p = 0.01368 and p = 0.0194, respectively). Resorption was positively associated with age of patient (p = 0.00606). These results may support early extraction of impacted 3rd molars especially in cases with a mesio-angulation of 60 degrees or more and an apical location in proximity to the distal root of the 2nd molar.
Section of Periodontology, Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, Israel.
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CE
Nemcovsky
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H
Libfeld
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Y
Zubery
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000539:Alveolar Process / Q000000981:diagnostic imaging / Q000473:pathology; D001862:Bone Resorption / Q000000981:diagnostic imaging / Q000209:etiology; D003795:Dental Sac / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008963:Molar / Q000000981:diagnostic imaging / Q000473:pathology*; D008964:Molar, Third / Q000000981:diagnostic imaging / Q000473:pathology*; D015588:Observer Variation; D010483:Periapical Diseases / Q000150:complications; D010513:Periodontal Ligament / Q000473:pathology; D015995:Prevalence; D011859:Radiography; D012390:Root Canal Therapy; D012391:Root Resorption / Q000000981:diagnostic imaging / Q000209:etiology*; D012737:Sex Factors; D014081:Tooth Extraction; D014097:Tooth, Unerupted / Q000150:complications* / Q000000981:diagnostic imaging