A comparison of treatment impacts between Invisalign aligner and fixed appliance therapy during the first week of treatment

Am J Orthod Dentofacial Orthop. 2007 Mar;131(3):302.e1-9. doi: 10.1016/j.ajodo.2006.05.031.


Introduction: The aim of this study was to evaluate the differences in quality of life impacts between subjects treated with Invisalign aligners (Align Technology, Santa Clara, Calif) and those with fixed appliances during the first week of orthodontic treatment.

Methods: A prospective, longitudinal cohort study involving 60 adult orthodontic patients (33 with Invisalign aligners, 27 with fixed appliances) was completed by using a daily diary to measure treatment impacts including functional, psychosocial, and pain-related outcomes. A baseline survey was completed before the start of treatment; diary entries were made for 7 consecutive days to measure various impacts of the subjects' orthodontic treatment over time. The data were then analyzed for differences between treatment modalities in terms of the subjects' reported impacts from their orthodontic treatment.

Results: The baseline mean values did not differ between groups for pain reports (P = .22) or overall quality of life impact (P = .51). During the first week of treatment, the subjects in the Invisalign group reported fewer negative impacts on overall quality of life (P <.0001). The Invisalign group also recorded less impact in each quality of life subscale evaluated (functional, psychosocial, and pain-related, all P <.003). The visual analog scale pain reports showed that subjects in the Invisalign group experienced less pain during the first week of treatment (P <.0001). The subjects in the fixed appliance group took more pain medications than those in the Invisalign group at days 2 and 3 (both P <.007).

Conclusions: Adults treated with Invisalign aligners experienced less pain and fewer negative impacts on their lives during the first week of orthodontic treatment than did those treated with fixed appliances.

Publication types

  • Evaluation Study

MeSH terms

  • Adult
  • Epidemiologic Methods
  • Female
  • Humans
  • Male
  • Middle Aged
  • Orthodontics, Corrective / instrumentation*
  • Orthodontics, Corrective / methods
  • Orthodontics, Corrective / psychology
  • Pain / psychology*
  • Quality of Life / psychology*