title: Evaluation of compressive strength in the first premolars between young and elderly people: ex vivo study.
abstract: OBJECTIVE
  This study evaluated the compressive strength of first maxillary premolars from young and elderly people.
  
  
  BACKGROUND
  Findings have revealed that changes happening on dental structure lead to a higher susceptibility of tooth fracture.
  
  
  METHODS
  Thirty teeth were divided into four groups as follows: G I (n = 7) premolars of elderly patients with fused roots, G II (n = 8) premolars of elderly with separate roots, G III (n = 7) pre-molars of young people with fused roots and G IV (n = 8) premolars of young people with roots separated. The roots were placed in polyvinyl chloride (PVC) cylinder and embedded in acrylic resin. Afterward, the samples were subjected to fracture by compressive strength in a universal testing machine. Loads were applied in continuous and progressive speed of 0.5 mm/min until the moment of fracture. The values found underwent statistical analysis (ANOVA α = 0.05).
  
  
  RESULTS
  With regard to age, there was a statistical difference, the teeth of the elderly being more susceptible to fracture (p < 0.05). With regard to root morphology, no significant differences between both groups were observed (p > 0.05).
  
  
  CONCLUSIONS
  It was concluded that with the methodology employed, the age factor was important with regard to fracture resistance to compression.
authors.affiliation: Post-graduation Program in Dentistry, Fluminense Federal University (UFF), Niterói, RJ, Brazil.
authors.forename: Fernando
authors.initials: F
authors.lastname: de Noronha
authors.forename: Miriam F Z
authors.initials: MF
authors.lastname: Scelza
authors.forename: Licinio E
authors.initials: LE
authors.lastname: da Silva
authors.forename: Waldimir R
authors.initials: WR
authors.lastname: de Carvalho
mesh_terms: D000293:Adolescent; D000375:Aging / Q000502:physiology*; D001641:Bicuspid / Q000033:anatomy & histology / Q000502:physiology*; D001696:Biomechanical Phenomena; D019245:Compressive Strength; D003799:Dental Stress Analysis / Q000295:instrumentation; D006801:Humans; D008437:Maxilla; D008875:Middle Aged; D013314:Stress, Mechanical; D014082:Tooth Fractures / Q000503:physiopathology; D014092:Tooth Root / Q000033:anatomy & histology / Q000502:physiology; D055815:Young Adult