Orthodontic Tooth Movement With Accelerated Invisalign Therapy Using Acceledent Aura: A Randomized Clinical Trial
Phase: NA
Conditions: Malocclusion
Sponsor: University of North Carolina, Chapel Hill

 
Orthodontic Tooth Movement with Accelerated Invisalign Therapy in 
Conjunction with Acceledent Aura®: A Randomized Clinical Trial 
 
 
NCT number NCT02868554 
Document Date 08/01/2018 
 

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UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL 
SCHOOL OF DENTISTRY 
GRADUATE STUDENT MASTERS THESIS DEVELOPMENT PROGRAM 
 
ABSTRACT OF RESEARCH PLAN 
STUDENT: Brian Bragassa  
 
 
 
PROGRAM: Orthodontics 
TITLE OF PROJECT: Orthodontic tooth movement with Accelerated Invisalign therapy in 
conjunction with Acceledent Aura®: A Randomized Clinical Trial  
THESIS ADVISOR: Dr. Ching-Chang Ko 
ADVISOR’S SIGNATURE: 
COMMITTEE MEMBERS:   
DATE OF SUBMISSION: TBD 
 
 
 
Dr. Tate Jackson, DDS 
Dr. Bill Gierie, DDS 
Dr. Feng Chang Li, PhD 
 
ABSTRACT OF RESEARCH PLAN:  
Objective: The objective of this study is to investigate the effects of accelerated Invisalign 
and vibration therapy on rate of orthodontic tooth movement, activation of inflammation 
biomarkers as well as pain levels experienced during the initial 12 weeks of alignment.  
Significance: Invisalign® and other advances in orthodontic technology such as clear 
aligners, ceramic and lingual braces have met the esthetic demands of most orthodontic 
patients but duration of treatment continues to be one of the most challenging aspects of 
orthodontic practice.2 Accelerated orthodontic treatment presents several potential benefits 
and challenges to both, the orthodontic patient and provider. AcceleDent Aura® is an FDA 
approved class II medical device developed to accelerate tooth movement and reduce 
orthodontic treatment time.7 Orthodontic providers are prescribing accelerated Invisalign 
in conjunction with AcceleDent vibration therapy and achieving positive results. However, it 
remains unclear if vibration therapy or the accelerated Invisalign aligner schedule is 
responsible for the increased rate of tooth movement. More clinical research is needed to 
provide more clarity regarding the efficacy of vibration therapy on accelerated orthodontic 
tooth movement. 
Methods: Approximately 42 patients, between the ages of 18-65 years, will be consecutively 
recruited to participate in a randomized prospective clinical trial. Enrolled subjects will be 
randomly allocated into one of 3 groups: Standard Invisalign therapy (G1-control), 
Accelerated Invisalign therapy + vibration (G2) and Accelerated Invisalign therapy without 
vibration (G3). Data collection will include intra oral scans of both the maxillary and 
mandibular dentition at 5 different time points: TO (baseline), T1 (4 days), T2 (14 days), T3 
(6 weeks) and T4 (12 weeks). In addition, PerioPaper strips will be used to sample gingival 
crevicular fluid at each of the time points listed above. Research subjects will also be asked 
to complete a daily diary regarding their pain level during treatment. Data analysis will be 
completed using digital models and Ortho Insight 3D software. Little’s Irregularity Index will 
be used to specifically evaluate alignment of adjacent teeth and translational, and/or 
rotational, tooth movement will be evaluated by superimposing digital models recorded at 
the specific time points. Inflammation biomarkers will be analyzed with ELISA. Finally, the 

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statistical significance of our data will be evaluated with a 3 way repeated ANOVA as well as 
a post hoc comparison with Bonferri correction. P values less than .05 will be considered 
statistically significant.  
 
Specific Aims:  
In this study, we propose a randomized prospective clinical design to investigate effects of 
vibration therapy, using an AcceleDent Aura® device, on the rate of orthodontic tooth 
movement, activation of gingival crevicular fluid inflammation biomarkers and patient 
discomfort in conjunction with accelerated Invisalign therapy.  
 
Hypothesis: 
We propose vibration therapy will accelerate orthodontic tooth movement, increase 
inflammation biomarkers and reduce pain for orthodontic patients. 
 
Background: 
Align Technology©, Inc. developed Invisalign® in 1997 to meet the esthetic 
demands of orthodontic patients and providers. Invisalign patients receive a series of 
computer-assisted designed stereolithic clear retainers to incrementally resolve their 
malocclusion.  Invisalign® and other advances in orthodontic technology such as clear 
aligners, ceramic brackets and lingual braces offer options to address the esthetic demands 
of most orthodontic patients but duration of treatment continues to be one of the most 
challenging aspects of practice.2 
 
In 2008, OrthoAccel Technologies©, Inc. developed the AcceleDent device to 
accelerate tooth movement and reduce orthodontic treatment time. Patients receiving 
vibration therapy are instructed to bite down on the AcceleDent mouthpiece, which 
vibrates at a .25N (25 grams) force level with a 30 Hz frequency for 20 minutes per day.15 
The theory underlying AcceleDent and the use of vibration to expedite orthodontic tooth 
movement started in 1892 with the studies of Julius Wollf, who discovered bone adapts to 
pressure loads.5 In 2001, Astronauts in space attempted to use the principles of Wolff’s Law 
to maintain normal bone quality by working out and performing daily tasks while standing 
on a vibrating plate with the aid of elastic straps.6 In 2004, the effect of vibration therapy 
on bone density was further supported when increased bone density and strength was 
noted in post-menopausal women who received whole body vibration therapy.8 OrthoAccel 
claims vibration therapy using the AcceleDent device can reduce treatment time up to 50 
percent by accelerating the process of bone remodeling required for orthodontic tooth 
movement.9 In 2013, despite relatively little scientific evidence, the FDA approved 
AcceleDent as a class II medical device and orthodontic accessory to facilitate accelerated 
tooth movement. 
 
Invisalign therapy in conjunction with AcceleDent has been aggressively marketed 
towards the esthetically sensitive patient who, not so coincidentally, is the most concerned 
with duration of treatment. Some orthodontic providers using vibration therapy have 
deviated from the standard 2-week aligner schedule and recommend a 4-day aligner 
schedule. Orthodontic patients receiving accelerated Invisalign therapy in conjunction with 
AcceleDent claim reduced treatment time by as much as 50 percent. What is responsible 

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for the positive results? The accelerated tooth movement might simply be the result of the 
accelerated Invisalign therapy, which would raise the question of whether vibration 
therapy and the cost associated with AcceleDent is justified. 
 
Accelerated orthodontic tooth movement may offer many benefits to both, the 
patient and the orthodontist.  Reduced treatment time reduces the burden of orthodontic 
treatment by decreasing risk for undesired treatment sequelae (e.g., white spot lesion, 
caries, gingivitis, etc) and potentially reduces the discomfort commonly associated with 
orthodontic treatment.12 Orthodontists benefit from accelerated tooth movement for 
multiple reasons pertaining to practice management and increased profitability. 
Orthodontists using accelerated treatment techniques have reported increased profit 
margins due to reduced chair time and increased organic growth due to differentiation of 
the practice. 2 
  
There are also potential negative outcomes associated with accelerated orthodontic 
tooth movement. For the patient, there is a potential increased risk for root resorption and 
increased treatment fees. 2 Most orthodontists are charging between $700-800 for 
AcceleDent therapy in addition to the normal orthodontic fee. How can Orthodontists 
expect patients to pay a higher fee over a shorter treatment period? How will this affect the 
patient’s ability to pay?  
 
Further, the mechanism underlying any increased orthodontic tooth movement due 
to vibration remains unclear. Studies on a cellular level have shown a promising but 
complicated mechanism of how vibration may enhance activation of various cell 
proliferation and differentiation molecules within the periodontal ligament (PDL) stem 
cells as well as increase levels of gingival inflammation biomarkers.12 For example, 
vibration therapy might accelerate breakdown of the cellular cytoskeleton, increase actinG 
trafficking into the nucleus, increase Runx2 gene expression, and thus facilitate bone 
formation.1 Whether this mechanotransduction mechanism can be translated into clinical 
tooth movement is unknown and its clinical evidence remains to be elucidated. 
 
In this study, we propose a randomized prospective clinical design to investigate 
effects of AcceleDent vibration therapy on the efficiency of tooth movement, on the 
activation of gingival crevicular fluid biomarkers and on patient discomfort in conjunction 
with accelerated Invisalign therapy.  
  
Methods: 
1. Study Design: 
a. In this study, we propose a single-blinded (Invisalign faculty) randomized 
prospective paralleled clinical trial to investigate effects of AcceleDent vibration 
therapy on the efficiency of tooth movement, on the activation of gingival 
crevicular fluid biomarkers and on patient discomfort in conjunction with 
accelerated Invisalign therapy. Enrolled subjects will be randomly allocated into 
one of 3 groups: Standard Invisalign therapy (G1-control), Accelerated Invisalign 
therapy + vibration (G2) and Accelerated Invisalign therapy without vibration (G3). 
Patients allocated to the standard Invisalign group will change aligners every 2 

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weeks while the both intervention groups will change aligners every 4 days. 
Patients allocated to the vibration group will receive an AcceleDent Aura device 
and bite down on the mouthpiece for 20 minutes/day. The AcceleDent Aura device 
vibrates at a .25N (25 grams) force level with a 30 Hz frequency. Data collection 
will include intra oral scans of both the maxillary and mandibular dentition at 
5 different time points: TO (baseline), T1 (4 days), T2 (14 days), T3 (6 weeks) 
and T4 (12 weeks). In addition, PerioPaper strips will be used to sample 
gingival crevicular fluid at each of the time points listed above. Research 
subjects will also be asked to complete a daily diary regarding their pain level 
during treatment. Treatment plans for enrolled patients will be created using 
Invisalign’s proprietary software: Clincheck Pro®. To reduce treatment plan 
variability and reduce potential sources of error, Dr. Bill Gierie, who is an “Elite 
Top 1% Invisalign provider” and also a member of the exclusive North American 
Invisalign Clinical Advisory Board, will approve each treatment plan. Dr. Gierie 
will also be blinded to any patients participation within the study in order to 
eliminate potential bias. 
2. Recruitment: 
a. Participants will be conveniently recruited from the sample population of 
individuals seeking Invisalign orthodontic therapy within the UNC Graduate 
Orthodontic Clinic. Benefits for participants will include complementary vibration 
therapy using the AcceleDent Aura device, which is an estimated value of $800. 
Financial reimbursement will also be offered to offset any parking fees associated 
with the study.  
3. Power Analysis: 
a. Our study will have 3 groups for evaluation: G1 control (Invisalign on a 2week 
aligner schedule) and 2 intervention groups, G2 and G3 (each on an 
accelerated 4 days aligner schedule). The only difference between the 
intervention groups will be the use of vibration (G2 with vibration vs G3 
without vibration). The expected rate of tooth movement for G1 will be 
.04mm/day (.25mm/week or .5mm/2 weeks) while the expected rate of tooth 
movement for G2 and G3 will be .28mm/day (.5mm in 4 days). The standard 
deviation is assumed 0.1 for three groups. Based on our sample calculation to 
achieve an adequate power, we will attempt to recruit a total of 42 patients to 
account for a dropout rate of 30%. Ideally, we would like to have a total sample 
size of 21 patients to ensure each of 3 study groups will have 7 patients, which 
will achieve more than 0.8 power even under a Bonferroni correction for 
multiple comparisons.  
4. Randomization: 
a. Our patients will be randomly allocated into the 3 groups based on a block 
randomization with size 6. The list will be independently generated by our 
study biostatistician.   
5. Type I error and statistical significance:  
a. P values less than .05 will be considered statistically significant in the overall 
test 
6. Inclusion Criteria: 
a. Males or females over the age of 18 years old desiring orthodontic treatment.  

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b. Adult dentition with all upper and lower front teeth present and any premolar and 
molar combination in the upper posterior of two teeth on each side. 
c. Normal pulp vitality and healthy periodontal tissues as determined by intraoral 
exam. 
d. Good health as determined by medical history. 
e. Willingness and ability to comply with study procedures, attend study visits, and 
complete the study. 
f. The ability to understand and sign a written informed consent form, which must be 
signed prior to initiation of study procedures. 
7. Exclusion Criteria: 
a. Patient under the age of 18 years old 
b. Patients diagnosed with systemic diseases such as diabetes, hypertension (high 
blood pressure), temporomandibular disorders (jaw disorders), or craniofacial 
syndromes. 
c. Severe malocclusions that would require adjunctive procedures other than 
Invisalign. These include impacted teeth, closure of extractions spaces. 
d. Significant periodontal disease (> 4mm pocket depth or >2 mm of recession on 
upper anterior teeth). 
e. Active caries not under care of either a dentist or periodontist. 
f. Chronic daily use of any non-steroidal anti-inflammatory medication, estrogen, 
calcitonin, or corticosteroids. 
g. History of use or current use of any bisphosphonate medication or other medication 
for treatment of osteoporosis. 
h. Current smoker (must not have smoked in the last 6 months). 
i. Failing to comply with research protocols 
8. Arms: 
a. Control Group (G1): 14 patients, standard Invisalign therapy with 2 week 
aligner schedule 
a. Intervention Group (G2): 14 patients, accelerated Invisalign + vibration  
i. AcceleDent device 20 minutes/day per manufacturer’s instructions  
b. Intervention Group (G3): 14 patients, accelerated Invisalign + no vibration 
7. Clinical Trial Protocol: 
a. Visit #1: Clinical Screening with UNC Orthodontic Faculty (clinical purposes 
only) 
i. Brief discussion of findings with patient and eligibility for Invisalign 
 
b. Visit #2: Clinical exam and records (clinical purposes only), 30 days post visit 
#1 
i. Completion of medical history 
ii. Completion of extra and intra oral exams 
iii. Completion of alginate impressions 
iv. Photographs (extra and intra oral) 
v. Xrays- Panoramic and Cephalometric 
 
c. Visit #3: Treatment Plan Presentation (Experimental Baseline), 60 days post 
visit #1 

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i. Clinical Procedures: 
1. Treatment plan presentation 
a. Each treatment plan will be approved by Dr. Bill Gierie 
who will be blinded to a patient’s study participation 
2. Invisalign impressions with PVS material 
ii. Research Procedures: 
1. Study recruitment  
2. Informed Consent 
3. iTero intraoral scan 
4. Completion of the Inclusion/Exclusion Case Report Form 
 
d. Visit #4: (120 days post visit #1/Day #1 of active treatment) 
i. Clinical Procedures: 
1. Intraoral exam and intraoral photographs 
2. Deliver aligner number 1 and usage instructions 
ii. Research Procedures: 
1. Deliver AcceleDent Aura device along with instructions 
2. Collection of gingival crevicular fluid biomarkers 
3. Completion of Faces Pain Scale  
4. Deliver daily diaries 
 
e. Visit #5: (125 days post visit #1/ Day #5 of active treatment) 
i. Clinical procedures: 
1. Deliver aligners 2-4 to accelerate Invisalign groups and aligner 
schedule instructions 
ii. Research Procedures: 
1. iTero intraoral scan 
2. Collection of gingival crevicular fluid biomarkers 
3. Completion of Faces Pain Scale and Adverse Event Form 
 
f. Visit #6: (134 days post visit #1/Day #14 of active treatment) 
i. Clinical procedures 
1. Intraoral exam and intraoral photographs 
2. Place attachments (35% phosphoric acid etch, L-pop self-
etching primer, composite resin, LED light curing for 30 secs) 
3. Deliver more aligners: 2-3 to control group and 5-11 to 
intervention groups (accelerated Invisalign) 
ii. Research Procedures: 
1. iTero intraoral scan 
2. Collection of gingival crevicular fluid biomarkers 
3. Completion of Faces Pain Scale and Adverse Event Form 
 
g. Visit #7: (176 days post visit #1/6 weeks of after treatment) 
i. Clinical procedures: 
1. Intraoral exam and intraoral photographs 

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ii. Deliver more aligners: 4-6 to control group and 11-21 to intervention 
groups (Accelerated Invisalign) 
h. Research: 
1. iTero intraoral scan 
2. Collection of gingival crevicular fluid biomarkers 
3. Completion of Faces Pain Scale and Adverse Event Form 
 
i. Visit #8: (218 days post visit #1/12 weeks of active treatment) (End of clinical 
study) 
i. Clinical Procedures: 
1. Intraoral exam and photographs 
2. Deliver more aligners to both control (7-12) and intervention 
groups (21-30) 
3. Deliver AcceleDent Aura devices to participants in control and 
non-vibration intervention group. 
ii. Research Procedures: 
1. iTero intraoral scan 
2. Collection of gingival crevicular fluid biomarkers 
3. Completion of Faces Pain Scale and Adverse Event Form 
 
j. Visit #9: (260 days post visit #1) 
i. Clinical Procedures: 
1. Intraoral exam and photographs 
2. Deliver any remaining aligners 
3. iTero Scan for any necessary revisions 
 
k. Visit #10: (302 days post visit #1) 
i. Clinical Procedures: 
1. Intraoral exam and photographs 
2. Deliver revision aligners as needed 
l. Visit #11: Treatment complete, ensure patient satisfaction 
i. Clinical Procedures: 
1. Intraoral exam and photographs 
2. Completion of alginate impression 
3. Completion of post tx pano and cephalometric xrays 
4. Deliver Essix retainers to prevent relapse 
8. Data Collection: 
b. 3D intraoral scanning protocol 
i. T0- baseline 
ii. T1- 4 days 
iii. T2- 14 days 
iv. T3- 6 weeks 
v. Tfinal- 12 weeks 
c. Gingival Crevicular Fluid Sampling 
i. T0- baseline 
ii. T1- 4 days 

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iii. T2- 14 days 
iv. T3- 6 weeks 
v. Tfinal- 12 weeks 
d. Orthodontic Pain Assessment 
i. Daily dairy using Faces Pain Scale 
9. Monitoring Compliance: 
a. Daily diary usage log 
b. AcceleDent Fast Trac usage report 
9. Adverse Events: 
a. Patients who experience an adverse event or reaction such as: uncontrolled 
pain or allergy will be disenrolled from the study and allowed to continue 
Invisalign therapy using the standard two-week aligner schedule. In addition, 
non-compliant patients will be disenrolled from the study and recommend to 
continue Invisalign therapy using the standard protocol. 
10. Data Analysis: 
a. Tooth leveling and alignment 
i. Little’s Index 
b. Tooth rotations and translations  
i. Euler’s Law of Motion (6 degrees of freedom) 
ii. 3D surface mapping 
c. Alternative measurement options 
i. Screw Method 
d. Inflammation biomarkers within gingival crevicular fluid 
i. ELISA 
e. Orthodontic Pain Assessment 
i. Faces Pain Scale 
11. Statistical Analysis: 
a. In order to complete statistical analysis for maxillary and mandibular dentition, we 
will compare the five time points within each group as well as the three groups 
across each time point. 
b. Our primary statistical method will be a three-way repeated measurement 
ANOVA, with the main effects being: vibration, aligner schedule, and time. The 
ANOVA measurement will identify significant differences within the data and 
the post hoc comparison will determine which specific variables are involved. 
In order for a relationship to be considered statistically significant, the p-value 
must be less than .05. 
c. One additional method for statistical analysis could be a survival analysis 
which would be more favorable in the case our study experiences a high 
volume of drop-outs during treatment. 
12. Patient Confidentiality: 
a. Records related to this research study that involve perennial information will 
only be accessible by the primary research committee and direct assistants. 
Records will be stored on encrypted, password-protected computer hard 
drives. A 3-digit code number will be used rather than the subject's name to 
identify the specific data related to his/her involvement in the study. Only 
the research investigators will have access to the file that links personal 

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information to the 3-digit codes, and this file will be stored in a separate 
location from the actual research data. 
 
Project Timeline: 
 
Item 
Date 
Study Design; IRB submission (Teresa) 
Spring 2016 
Background Research 
March 2016 
Loose conceptual framework 
March 2016 
Presentation 
April 2, 2016 
Protocol 
May 16, 2016 
IRB approval 
May 2016 
Select study population 
August 2016 
Clinical Trial 
November 2016 
Collect Data 
January 2017 
Research Day Poster 
March 2018 
Thesis Defense 
March 2018 
AAO Presentation 
April 2018 
Manuscript submissions 
April 2018 
 
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