title: Tooth-wear patterns in subjects with Class II Division 1 malocclusion and normal occlusion.
abstract: BACKGROUND
  The aim of this study was to investigate the prevalence of tooth wear in adolescents with Class II malocclusion, compared with those with normal occlusion.
  
  
  METHODS
  The sample consisted of dental casts obtained from 310 subjects, divided into 3 groups: group 1, 110 subjects with normal occlusion (mean age, 13.51 years); group 2, 100 complete Class II Division 1 patients (mean age, 13.44 years); and group 3, 100 half-cusp Class II Division 1 patients (mean age, 13.17 years). Dental wear was assessed by using a modified version of the tooth-wear index. The 3 groups were compared by means of the Kruskal-Wallis and Dunn tests, considering the frequency and the severity of wear on each surface of each group of teeth. The level of statistical significance was set at 5%.
  
  
  RESULTS
  The normal occlusion group had statistically greater tooth wear on the palatal surfaces of the maxillary central incisors and the incisal surfaces of the maxillary canines than the corresponding surfaces in both Class II malocclusion groups. The complete and half-cusp Class II Division 1 malocclusion groups had statistically greater tooth wear on the occlusal surfaces of the maxillary second premolar and first molar, the occlusal surfaces of the mandibular premolars, and the buccal surfaces of the mandibular posterior teeth compared with the normal occlusion group. The half-cusp Class II Division 1 malocclusion group had significantly greater tooth wear on the incisal surfaces of the mandibular incisors compared with the complete Class II Division 1 malocclusion group.
  
  
  CONCLUSIONS
  Subjects with normal occlusion and complete or half-cusp Class II Division 1 malocclusions have different tooth-wear patterns. Tooth wear on the malocclusion subjects should not be considered pathologic but rather consequent to the different interocclusal tooth arrangement.
authors.affiliation: Department of Orthodontics, Bauru Dental School, University of São Paulo, Alameda Octávio Pinheiro Brisolla 9-75, Bauru, São Paulo, 17012-901, Brazil. jansong@travelnet.com.br
authors.forename: Guilherme
authors.initials: G
authors.lastname: Janson
authors.forename: Paula Vanessa Pedron
authors.initials: PV
authors.lastname: Oltramari-Navarro
authors.forename: Renata Biella Salles
authors.initials: RB
authors.lastname: de Oliveira
authors.forename: Camila Leite
authors.initials: CL
authors.lastname: Quaglio
authors.forename: Sílvia Helena de Carvalho
authors.initials: SH
authors.lastname: Sales-Peres
authors.forename: Bryan
authors.initials: B
authors.lastname: Tompson
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008312:Malocclusion, Angle Class II / Q000150:complications / Q000503:physiopathology*; D015203:Reproducibility of Results; D057085:Tooth Wear / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology