title: Factors related to orthodontic treatment time in adult patients.
abstract: BACKGROUND
  The length of time that it takes an orthodontist to treat adult patients varies widely.
  
  
  OBJECTIVE
  The aim of this study was to investigate how different variables influence treatment time.
  
  
  METHODS
  Seventy clinical case reports of successfully treated adult patients were examined. The patients were selected from 4,723 records held by three experienced orthodontists. The influence exerted by the following variables on treatment time was assessed: age, sex, facial pattern, severity of malocclusion (measured by the PAR index), sagittal relationship of canines, type of brackets (ceramic or metal), tooth extractions, missed appointments and orthodontic appliance issues/breakages, the latter being the dependent variable. Assessment was performed by multiple linear regression analysis, followed by the stepwise method with p < 0.05.
  
  
  RESULTS
  The number of times a patient missed their appointment (no-show) (R² = 14.4%, p < 0.0001) and the number of appliance issues/breakages (R² = 29.71%, p = 0.0037) significantly affected variability in treatment time, and these two variables together can predict 43.75% (R² total) of the overall variability in treatment time. Other factors, such as canine relationship at the beginning of treatment, bracket type (metal or ceramic), tooth extractions, age at start of treatment, severity of the initial malocclusion, sex and facial pattern had no significant bearing on treatment time.
  
  
  CONCLUSIONS
  The duration of orthodontic treatment in adults, when performed by experienced orthodontists, is mainly influenced by factors related to patient compliance. However, several factors which were not included in this study may contribute to variability in orthodontic treatment time.
authors.forename: Ana Camila Esteves de Oliveira
authors.initials: AC
authors.lastname: Melo
authors.forename: Lilianne Oliveira Thiers
authors.initials: LO
authors.lastname: Carneiro
authors.forename: Luana Farias
authors.initials: LF
authors.lastname: Pontes
authors.forename: Rodolpho Lobão
authors.initials: RL
authors.lastname: Cecim
authors.forename: José Nazareno Rufino
authors.initials: JN
authors.lastname: de Mattos
authors.forename: David
authors.initials: D
authors.lastname: Normando
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000704:Analysis of Variance; D001071:Appointments and Schedules; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008310:Malocclusion / Q000473:pathology / Q000628:therapy*; D008875:Middle Aged; D016910:Orthodontic Brackets; D009971:Orthodontics, Corrective; D010349:Patient Compliance; D012189:Retrospective Studies; D012737:Sex Factors; D013995:Time; D013997:Time Factors; D014081:Tooth Extraction / Q000706:statistics & numerical data; D055815:Young Adult
keywords: Adult; Orthodontics; Time factors