Accelerated Invisalign Therapy in Conjunction With Acceledent Aura

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.

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 .25 N (25 grams) force level with a 30 Hz frequency for 20 minutes per day. The theory underlying AcceleDent and the use of vibration to expedite orthodontic tooth movement started in 1892 with the studies of Julius Wolff, who discovered bone adapts to pressure loads. 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. 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. 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. In 2013, despite relatively little scientific evidence, the US Food and Drug Administration (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 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. The purpose and primary specific aim of our study will be to determine the cause of the accelerated tooth movement. Because the vibration therapy is used in conjunction with an accelerated Invisalign aligner schedule, there is an assumption that the vibration therapy is promoting faster tooth movement. However, the current literature, from clinical trials, supporting the efficacy of vibration therapy on accelerated tooth movement is lacking.

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. 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.

There are also potential negative outcomes associated with accelerated orthodontic tooth movement. For the patient, there is a potential increased risk for root resorption, increased treatment fees and pain associated with treatment. At this time, there is no published data regarding the potential for orthodontic relapse following the accelerated orthodontic tooth movement. There are several publications supporting the fact that relapse is a known risk for conventional orthodontic treatment. The investigators can make the safe assumption that accelerated orthodontic treatment would be no different than conventional orthodontic therapy with regard to relapse potential. All orthodontic patients must be compliant with regard to orthodontic retention or relapse will be expected. Most orthodontists are charging between $700-800 for AcceleDent therapy in addition to the normal orthodontic fee. Finally, there is no published data regarding pain associated with accelerated Invisalign treatment.

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. 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. Whether this mechanotransduction mechanism can be translated into clinical tooth movement is unknown and its clinical evidence remains to be elucidated.

In this study, the investigators 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.