Introduction: The objective of our study was to determine if vibration therapy increases the efficiency and accuracy of incisor alignment, accuracy of overbite correction as well as decreases discomfort associated with accelerated (4-day) Invisalign®. Methods: 33 patients were enrolled in a double-blinded parallel, randomized prospective clinical trial at the UNC Department of Orthodontics. Participants were randomly allocated into one of 3 groups: 2-week aligner wear (G1, n=10), 4-day aligner wear without vibration (G2, n=12) and 4-day aligner wear with vibration (G3, n=11). 3-D virtual models of maxillary and mandibular dentition were captured at 2 different time points: Baseline (To) and following 12-weeks of treatment (Tfinal). Efficiency and accuracy of incisor alignment for 63 pre/ post-treatment dental arches was determined by using the percent reduction and percent accuracy of reduction in Proximal Contact Point Discrepancy Index (PCPDI). The accuracy of OB correction was determined for 29 pot-treatment models by measuring the percent accuracy of overbite correction (OB). Finally, discomfort and the need for analgesic medication was investigated for each subject at 4 time points (T4-days, T2-weeks, T6-weeks, Tfinal) using a Visual Analog Scale (VAS) and a survey, respectively. Results: There was a significant increase in the efficiency of incisor alignment between groups G1 (18.9%) and G3 (29.12%) (P= 0.003). However, there was also a significant decrease in the percent accuracy of incisor alignment between group G1 (48%) and G2 (36%)/G3 subjects (37%)(P= 0.023, .047). There was no significant difference in the percent accuracy of overall OB correction between the 3 groups (P= 0.331, .0664). However, the percent accuracy of simple OB correction was statistically greater than complex OB correction in within each group (P= 0.039, <0.001, .047). Pain scores tended to be higher for G2 subjects but the difference was only significant at one time point (T2-weeks) (P= 0.03). Vibration therapy did not significantly increase the efficiency/accuracy of incisor alignment (P= 0.089, 0.774) or the accuracy of OB correction (P= 0.33, 0.064) and decrease the pain associated with accelerated (4-day) Invisalign®(P= 0.59, 0.85). Conclusion: Accelerated (4-day) Invisalign® increases the efficiency but decreased the accuracy of incisor alignment when compared to a 2-week control group. Simple OB correction is significantly more accurate than complex OB correction when using Invisalign therapy. Vibration therapy has no effect on the efficiency and accuracy of incisor alignment, accuracy of OB correction nor the discomfort associated with accelerated (4-day) Invisalign®.