Clear Aligner Treatment with “In-Office” Virtual Model Set-Up and 3D Printing.

Abstract

Orthodontic treatment with clear aligners is increasingly popular in adult patients. Clear aligners can be applied more efficiently if virtual tooth movement setups and production of physical models did not require a third-party source. We here report digital orthodontic treatment with clear aligners to correct anterior tooth mal-alignment in a 28-year-old female patient. We scanned dental casts to create virtual models that we used to simulate orthodontic tooth movement. To create space to relieve crowding, we used arch expansion and interproximal re-approximation. Sequential virtual model setups were generated with the tooth movements programmed to be 0.3 ~ 0.4 mm in each step. We used an in-office 3D printer to produce physical models of virtual setups using polylactic acid material. Subsequently, we could fabricate clear aligners by use of physical models. At 3 and 7.5 months into treatment, we took dental impressions for midcourse correction due to off-tracking, i.e. predicted tooth movement not achieved as expected. After 11 months of treatment, alignment of the anterior teeth, incisor overjet and overbite had obviously improved. Meanwhile the occlusal contacts of the posterior teeth were maintained throughout the treatment period. The post-treatment occlusion improved significantly, both functionally and esthetically, and remained stable during the retention phase.