title: The association between orthodontic treatment and third molar position, inferior alveolar nerve involvement, and prediction of wisdom tooth eruption.
abstract: OBJECTIVE
  The present study aims to compare mandibular third molar position in relation to the mandibular ramus, mandibular third molar angulation, potential impaction and nerve involvement in orthodontic treated versus untreated subjects.
  
  
  METHODS
  The sample consisted of 300 panoramic radiographs 119 males (mean age 16.9 years); 181 females (mean age 16.8 years), contrasting an orthodontically treated (n = 150) to an untreated group (n = 150). Only patients with a full mandibular dentition were included. Pell and Gregory (Dent Digest 39: 330-338, 1933), Winter (Principles of exodontia as applied to the impacted third molars, 1926) and Félez-Gutierrez modified by Gomes (Study of nerve lesion following mandibular third molar surgery, 2011) classifications were used. Radiological information was used to predict eruption. Data was analyzed using frequency analysis and Chi-square testing.
  
  
  RESULTS
  220 lower wisdom teeth (73.3%) were impacted in the treated group, opposed to 236 impacted lower wisdom teeth (78.7%) in the untreated group. A close relation with the mandibular nerve was observed 125 times (41.7%) in the treated group, opposed to an incidence of 112 (37.3%) in the untreated group. The differences were not statistically significant. A partial eruption was predicted for 153 (51%) lower wisdom teeth in the treated group, opposed to 106 (35%) in the untreated group and an impossible eruption in 67 (22%) in the treated group, opposed to 130 (43%). These differences were statistically significant (p < 0.05).
  
  
  CONCLUSIONS
  The significant outcomes indicate that orthodontically treated patients may develop a higher likeliness to partially erupted third molars, which potentially leads to local clinical morbidities, such as pericoronitis and caries on adjacent teeth. In this context, it may support third molar extractions at an earlier stage in particular cases.
authors.affiliation: Dentistry, Department of Oral Health Sciences-Orthodontics, KU Leuven and Dentistry UZ Leuven, Kapucijnenvoer 7, 3000, Leuven, Belgium, anneliemiclotte@gmail.com.
authors.forename: Annelie
authors.initials: A
authors.lastname: Miclotte
authors.forename: Ademir
authors.initials: A
authors.lastname: Franco
authors.forename: Maria Eugenia
authors.initials: ME
authors.lastname: Guerrero
authors.forename: Guy
authors.initials: G
authors.lastname: Willems
authors.forename: Reinhilde
authors.initials: R
authors.lastname: Jacobs
mesh_terms: D000293:Adolescent; D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008340:Mandibular Nerve / Q000000981:diagnostic imaging*; D008964:Molar, Third / Q000000981:diagnostic imaging*; D009971:Orthodontics, Corrective / Q000706:statistics & numerical data*; D011862:Radiography, Panoramic; D014078:Tooth Eruption; D014095:Tooth, Impacted / Q000000981:diagnostic imaging*; D055815:Young Adult
references.citation: Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2001 Oct;92(4):377-83
references.pmid: 11598570
references.citation: Community Dent Health. 1988 Jun;5(2):121-38
references.pmid: 3165039
references.citation: Int J Oral Maxillofac Surg. 2012 Oct;41(10):1270-4
references.pmid: 22464852
references.citation: Am J Orthod Dentofacial Orthop. 2011 Jul;140(1):10-6
references.pmid: 21724080
references.citation: Angle Orthod. 2009 Nov;79(6):1143-8
references.pmid: 19852607
references.citation: J Oral Maxillofac Surg. 2012 Jul;70(7):1507-14.e1-6
references.pmid: 22326171
references.citation: J Oral Maxillofac Surg. 2012 Sep;70(9 Suppl 1):S11-4
references.pmid: 22705213
references.citation: Cochrane Database Syst Rev. 2012 Jun 13;(6):CD003879
references.pmid: 22696337
references.citation: J Oral Maxillofac Surg. 2009 Feb;67(2):292-300
references.pmid: 19138602
references.citation: J Oral Maxillofac Surg. 2007 Oct;65(10):2011-7
references.pmid: 17884530
references.citation: J Oral Maxillofac Surg. 2003 Dec;61(12):1436-48
references.pmid: 14663809
references.citation: Int J Oral Surg. 1985 Feb;14(1):29-40
references.pmid: 3921477
references.citation: Br J Oral Maxillofac Surg. 2006 Oct;44(5):347-50
references.pmid: 16214273
references.citation: Int J Oral Maxillofac Surg. 2003 Oct;32(5):548-52
references.pmid: 14759117
references.citation: J Oral Maxillofac Surg. 2010 Dec;68(12):2935-42
references.pmid: 21095505
references.citation: Arch Oral Biol. 1999 Nov;44(11):925-34
references.pmid: 10580540
references.citation: Bratisl Lek Listy. 2009;110(2):110-1
references.pmid: 19408843
references.citation: Eur J Orthod. 2013 Aug;35(4):460-6
references.pmid: 22474212
references.citation: J Am Dent Assoc. 2012 Apr;143(4):363-9
references.pmid: 22467696
references.citation: Clin Oral Investig. 2014 Sep;18(7):1731-9
references.pmid: 24352580
references.citation: Surg Radiol Anat. 2014 Nov;36(9):847-50
references.pmid: 24752397
references.citation: J Oral Maxillofac Surg. 2007 Aug;65(8):1486-9
references.pmid: 17656272
references.citation: Am J Orthod Dentofacial Orthop. 1999 Jun;115(6):628-33
references.pmid: 10358244
references.citation: Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Jun;107(6):e58-64
references.pmid: 19464646