title: A study on occlusal stability in shortened dental arches.
abstract: OBJECTIVE
  The aim of this study was to verify the hypothesis that shortened dental arches constitute a risk to occlusal stability.
  
  
  METHODS
  Using cluster samples, 725 subjects with shortened dental arches comprising intact anterior regions and zero to eight occluding pairs of posterior teeth and 125 subjects with complete dental arches were selected. Subjects with shortened dental arches were classified into eight categories according to arch length and symmetry. Parameters for occlusal stability were interdental spacing, occlusal tooth wear, occlusal contact of incisors in intercuspal position, and vertical and horizontal overlap. Additionally, tooth mobility and overeruption of unopposed teeth were assessed. Influence of independent variables (dental arch category, age, gender, and residence) on the parameters for occlusal stability was assessed by one-way ANOVA and Tukey's multiple range tests.
  
  
  RESULTS
  Extreme shortened dental arches (zero to two pairs of occluding premolars) had significantly more interdental spacing, occlusal contact of incisors, and vertical overlap compared to complete dental arches. Occlusal wear and prevalence of mobile teeth were highest in these categories. The category with three to four occluding premolars had significantly more interdental spacing and, for the older age group, more anterior teeth in occlusal contact compared to complete dental arches. Age was consistently associated with increased changes in occlusal integrity.
  
  
  CONCLUSIONS
  Signs of increased risk to occlusal stability seemed to occur in extreme shortened dental arches, whereas no such evidence was found for intermediate categories of shortened dental arches.
authors.affiliation: Department of Restorative Dentistry, Faculty of Dentistry, Muhimbili University College of Health Sciences, Dar es Salaam, Tanzania.
authors.forename: Paulo T N
authors.initials: PT
authors.lastname: Sarita
authors.forename: Cees M
authors.initials: CM
authors.lastname: Kreulen
authors.forename: Dick J
authors.initials: DJ
authors.lastname: Witter
authors.forename: Martin
authors.initials: M
authors.lastname: van't Hof
authors.forename: Nico H J
authors.initials: NH
authors.lastname: Creugers
mesh_terms: D000328:Adult; D000367:Age Factors; D000704:Analysis of Variance; D001641:Bicuspid / Q000473:pathology; D003724:Dental Arch / Q000473:pathology / Q000503:physiopathology*; D003766:Dental Occlusion; D006801:Humans; D007180:Incisor / Q000473:pathology; D007576:Jaw, Edentulous, Partially / Q000145:classification / Q000503:physiopathology*; D008310:Malocclusion / Q000145:classification; D012307:Risk Factors; D012737:Sex Factors; D014070:Tooth / Q000473:pathology; D019217:Tooth Attrition / Q000145:classification; D014086:Tooth Mobility / Q000145:classification; D014716:Vertical Dimension