title: Variability of the dental surface: effects on orthodontic treatment.
abstract: OBJECTIVE
  The Author studied the variability of the vestibular surfaces of tooth usually involved in orthodontic treatment.
  
  
  METHODS
  200 model casts of Italian subject with complete permanent dentition have been analyzed studying the clinical crown dimension and the angulations of tangents drawn at 3 and 4 mm.
  
  
  RESULTS
  The authors found differences in the vestibular surfaces curvature in the last teeth of each series, more accemptuated in the lower than in the upper arch.
  
  
  CONCLUSIONS
  The conclusions of this study are related to the use of orthodontic straight wire appliances. The use of standard values with a complete torque, independently from the individuals, is based on the hypothesis of equal positioning on the tooth surface and related to the teeth axis. A variation in the torque of the upper central incisor for different kinds of straight wire appliance related to extreme variation of vestibular curvature is hypothesised.
authors.affiliation: Department of Odontostomatologic Science, Università La Sapienza, Rome. gabriella.galluccio@uniroma1.it
authors.forename: Gabriella
authors.initials: G
authors.lastname: Galluccio
mesh_terms: D000293:Adolescent; D001696:Biomechanical Phenomena; D003799:Dental Stress Analysis; D019229:Dentition, Permanent; D006801:Humans; D003765:Models, Dental; D009811:Odontometry; D016382:Orthodontic Appliance Design; D009969:Orthodontic Wires / Q000706:statistics & numerical data; D009970:Orthodontics / Q000295:instrumentation / Q000379:methods; D010347:Patient Care Planning; D019228:Tooth Crown / Q000033:anatomy & histology*; D014087:Tooth Movement Techniques / Q000295:instrumentation* / Q000706:statistics & numerical data; D019415:Torque; D055815:Young Adult