Predictability of overbite control with the Invisalign appliance

Abstract

Introduction: Control of overbite is considered essential in achieving ideal orthodontic outcomes. Questions have been raised regarding the accuracy of ClinCheck software (Align Technology, Santa Clara, Calif) in predicting posttreatment outcomes with Invisalign, with the paucity of well-researched literature available on this topic. This research aimed to investigate and determine the accuracy of Invisalign (Align Technology) in correcting a deep overbite by comparing the outcomes predicted by ClinCheck with achieved posttreatment outcomes.

Methods: A retrospective study was conducted using pretreatment and posttreatment intraoral scans and predicted outcome (ClinCheck) stereolithography files of 42 adult patients consecutively treated with Invisalign from January 2014 and completed before July 2018, selected from the files of 1 experienced orthodontist. Patients included in the study were treated without extractions and with a minimum of 14 dual arch Invisalign aligners using a 2-weekly aligner change protocol. The pretreatment, posttreatment, and predicted outcome stereolithography files for each patient were imported into Geomagic Control X (3D Systems, Rock Hill, SC) software to measure overbite.

Results: The deeper the patient's initial overbite and the greater the amount of programmed reduction in overbite according to ClinCheck, the greater the discrepancy in overbite expression posttreatment. ClinCheck over-predicted overbite reduction in 95.3% of patients in which, on average, only 39.2% of the prescribed overbite reduction was expressed.

Conclusions: Overbite reduction may result in suboptimal outcomes when using the Invisalign appliance unless remedial measures are employed. The deeper the initial overbite, the more challenging it is to achieve the prescribed posttreatment overbite.