|Year : 2016 | Volume
| Issue : 2 | Page : 97-101
Lightning fast orthodontic therapy
Shivendra Pal Singh1, Nidhi Rathore2, Asavari Desai3, Garima Chitkara4
1 Department of Periodontology and Oral Implantology, Eklavya Dental College, Rajasthan University of Health Sciences, Kotputli, India
2 Department of Orthodontics and Dentofacial Orthopaedics, Eklavya Dental College, Rajasthan University of Health Sciences, Kotputli, India
3 Department of Orthodontics, Manipal College of Dental Sciences, Manipal University, Mangalore, Karnataka, India
4 Department of Orthodontics and Dentofacial Orthopaedics, DAPMRV Dental College, Rajiv Gandhi University of Health Sciences, Bangalore, Karnataka, India
|Date of Web Publication||3-May-2016|
73, Brij Vihar, Jagatpura, Near Jagatpura Flyover, Jaipur, Rajasthan
The long duration of orthodontic treatment is a major deterrent for young and adult patients alike. This had led to researchers focusing on ways to shorten treatment time and the introduction of various treatment modalities. Among the highly invasive procedures are corticotomy with flap elevation. Microinvasive procedures include corticision, piezocision, alveocentesis, and laser facilitated corticotomy. Recently a noninvasive procedure AcceleDent system has been introduced. Apart from these, various drugs have also been successfully used since long but with no guaranteed safety. The aim of this article is to review the various options available to speed up the orthodontic tooth movement.
Keywords: AcceleDent, alveocentesis, corticotomy, laser facilitated corticotomy, orthodontic tooth movement, piezocision
|How to cite this article:|
Singh SP, Rathore N, Desai A, Chitkara G. Lightning fast orthodontic therapy. Univ Res J Dent 2016;6:97-101
| Introduction|| |
There has been a phenomenal rise in the number of adults seeking orthodontic treatment, but they are reluctant usually due to the long duration of treatment. Recently numerous modalities have been introduced to expedite tooth movement. Predictable but highly invasive surgical procedures such as corticotomy assisted orthodontics, have been used since many years. Currently available microinvasive approaches are corticision,, piezocision,, and alveocentesis. Various drugs have also been successful; however, safety is not assured.,,, Laser facilitated flapless corticotomy offers an attractive option. Very recently a noninvasive procedure, AcceleDent system has been introduced that claims to reduce the treatment time by 30–40%.
| Historical Review|| |
Surgical intervention to affect the alveolar housing, and thereby tooth movement has been described in different forms over the past 100 years. Heinrich Kole was the first to describe corticotomy-facilitated orthodontics in 1959. He believed that the continuity and thickness of the denser layer of cortical bone offers the most resistance to rapid tooth movement. Kole attributed the accelerated tooth movement by selective corticotomy to moving “blocks of bone” and this interpretation of the rapid tooth movement prevailed until Wilcko's publication in 2001.,
Wilcko discovered that the rapid tooth movement was due to transient localized demineralization-remineralization process in the bony alveolar housing and was not the result of bony block movement as suggested by Kole. Wilcko et al. combined the refined corticotomy-facilitated orthodontic technique with alveolar augmentation using particulate bone graft and named the orthodontic and periodontal aspects of this procedure the accelerated osteogenic orthodontics (AOO) technique, and more recently, the periodontally AOO (PAOO) surgical technique, respectively. This technique is claimed to reduce the orthodontic treatment time to 1/3rd the time of conventional orthodontics in majority of cases.,
Cruz et al. in 2004 were the first to carry out a human study on the effect of low-intensity laser therapy on orthodontic tooth movement. They showed that the irradiated canines were retracted at a rate of 34% greater than the control canines over a period of 60 days.
An alternative surgical approach to accelerate tooth movement was introduced by Park et al. in 2006 and Kim et al. in 2009 known as corticision which is considered to be a microinvasive technique.
Vercelotti and Podesta in 2007 introduced the use of piezosurgery, instead of burs, in conjunction with the conventional flap elevations to create an environment conducive to rapid tooth movement.
Dibart et al. in 2009 described a minimally invasive procedure piezocision, which uses a piezoelectric knife instead of mallet to give labial/buccal cortical incisions with no involvement of palatal or lingual cortex.,
A new microinvasive technique called alveocentesis was introduced in 2011, which stimulates cytokine activity thereby, accelerating alveolar bone remodeling. This new technique called the PROPEL system has been developed and patented for use as a simple, in-office procedure to stimulate alveolar bone remodeling. The micro-osteoperforations created by PROPEL system harnesses the body's own biology to create a cytokine effect and allows the teeth the move into clinically desired position in a more predictable and faster manner.
| Various Treatment Modalities to Hasten the Orthodontic Treatment Procedure: Pros and Cons|| |
Highly invasive procedures
These include corticotomy-facilitated tooth movement and PAOO. Although highly predictable, these procedures are very invasive and involve a lot of risk as well as postoperative complications. These procedures are based on the principle of regional acceleratory phenomenon (RAP) which is a part of healing event and is a localized osteoporosis state. The two main features of RAP include decreased regional bone density and accelerated bone turnover, which are believed to facilitate orthodontic tooth movement., By enhancing the various healing stages, corticotomy-facilitated tooth movement makes healing occur 2–10 times faster than normal physiologic healing. Corticotomy-facilitated tooth movement technique doubled the rate of orthodontic tooth movement. Histologically, the more active and extensive bone remodeling suggested that the acceleration of tooth movement associated with corticotomy is due to increased bone turnover and based on a RAP.
PAOO is a modified corticotomy facilitated orthodontic technique with the addition of alveolar augmentation which has an advantage of increasing the volume of alveolar bone and allows for correction of preexisting bony dehiscences and fenestrations. Potential advantages of the PAOO technique apart from reducing orthodontic treatment time from 1/3rd to 1/4th of traditional orthodontic treatment are that it also widens the scope of malocclusion treatment by enhancing the limits of tooth movement, decreases need for extractions, and enhances postorthodontic stability. It is useful for subtle enhancement of patient's profile by alveolar reshaping, less root resorption due to reduced resistance of bone, and for simultaneous rapid recovery of shallow unerupted teeth.,, Autogenous bone graft, allograft/xenograft (demineralized freeze-dried bone allograft [DFDBA]/DFDBA) and alloplastic materials can be used, however each have their own disadvantages. The disadvantage of using autogenous bone graft in lateral augmentation procedure is that it undergoes extensive resorption. Bovine bone xenograft provides only 37% of bone-to-graft contact after 6–7 months and biopsies from DFDBA-filled extraction sockets showed dead DFDBA particles embedded in dense connective tissue with little to no new bone formatio., A recent study revealed that alloplastic material (bioactive glass) was not able to contribute to vertical ridge augmentation and only a small gain in horizontal ridge width (average 1.1 mm) occurred 6 months after a guided bone regeneration procedure. PAOO is efficacious in the treatment of class I malocclusion with moderate to severe crowding, class II malocclusion requiring extraction/expansion, and mild class III cases. Initiation of orthodontic force should not be delayed more than 2 weeks after PAOO surgery. Case reports on PAOO are considered as weak evidence to support the advantages of this technique. A study was conducted by Ren et al. on beagle dogs which proves the efficacy of PAOO in accelerating orthodontic tooth movement.
Patients who are on long-term corticosteroids and those who are under medications such as bisphosphonates, nonsteroidal anti-inflammatory drugs (NSAIDs) are not good candidates for PAOO and therefore NSAIDs must be limited to only 1-week postoperatively for pain control. PAOO technique is safe, effective, extremely predictable, associated with less root resorption and reduced treatment time, and can reduce the need for orthognathic surgery in certain situations.,,,,,,,
High morbidity, invasiveness associated with these procedures, chances of damage to adjacent vital structure, extra surgical cost, postoperative pain, swelling, chances of infection, avascular necrosis, and low acceptance by the patient are among the major disadvantages of these corticotomy facilitated surgical procedures.
It is one of the minimally invasive alternatives to create a surgical injury to the bone without flap reflection. In this technique, a reinforced scalpel, and a mallet is used to go through the gingiva and cortical bone, without raising flaps. This surgical injury is deemed enough to induce the RAP effect and move the teeth rapidly during orthodontic treatment. Although innovative, corticision has a few major drawbacks: The inability to graft soft or hard tissues during the procedure to correct inadequacies. Clinical effectiveness of corticision have been proven along with benefits such as eliminating the obvious disadvantages of previous techniques which included flap elevation that resulted in crestal bone resorption and bone dehiscence.
Vercellotti and Podesta proposed the use of a piezoelectric knife instead of a high-speed surgical bur to decrease the surgical trauma and still achieve rapid tooth movement. It is a minimally invasive technique as the microincisons are limited to the buccal gingiva that allows the use of a piezoelectric knife to give osseous cuts to the buccal cortex and initiate the RAP without involving palatal or lingual cortex. Because of its micrometric and selective cut, a piezoelectric device produces safe and precise osteotomies without osteonecrosis damage., It also has the advantage of allowing for hard-tissue or soft-tissue grafting via selective tunneling to correct gingival recessions or bone deficiencies in patients. This novel approach is leading to short orthodontic treatment time, minimal discomfort, and great patient acceptance, as well as enhanced, or stronger, periodontium. Because of the added grafting (bone and/or soft-tissue), the periodontium is much thicker buccally. Piezocision stimulates the alveolar bone turnover through increased osteoclastic activity as early as 1-day and leads to RAP. It also allows to “bypass” the lag phase following the displacement phase and this forms the basis of rapid tooth movement compared to the conventional orthodontic treatment. The healing at the clinical level is much more predictable and much less painful. Therefore, the recovery is better and more acceptable to the patient.,, These physical modifications have proven to be beneficial in several ways: Increased stability of the clinical outcomes (less orthodontic relapse), increased scope of malocclusion correction (at times, avoiding orthognathic surgery), and reduced active orthodontic treatment time.
Performed using the PROPEL System, is a safe and effective microinvasive technique to accelerate orthodontics by about 50–60% faster movement than traditional orthodontics alone. PROPEL can be completed chair-side in minutes and does not require any advanced training. Unlike other systems, PROPEL is unique in that it can be targeted to specific teeth or quadrants rather than applied to the whole dentition at once in an uncontrolled fashion which may lead to anchorage issues. It also serves as a cost-effective alternative to implants in cases of adults with mutilated dentitions that often involves orthodontic closure of the edentulous region and with PROPEL, duration of treatment will be shortened making orthodontics an acceptable option. It has 0 recovery time, yields very little discomfort to the patient so the patients are able to return to their normal daily routine immediately and increases the rate of canine retraction by 2.3-fold. Micro-osteoperforation is a comfortable, and safe procedure to accelerate tooth movement, and significantly reduce the duration of orthodontic treatment.
Photobiomodulation or low-level laser therapy
It is one of the most promising approaches today. Laser light has been found to stimulate the proliferation of osteoclast, osteoblast, and fibroblasts, and thereby affect bone remodeling and accelerates tooth movement.,, Low level laser therapy accelerates tooth movement by 30–60%, erbium laser reduces or maintains the pulpal temperature thus eliminating the side effects on pulp. In techniques where burs and piezoelectric devices are used, the physical contact between the instrument head, and tissue is usually a source of discomfort whereas lasers are noncontact. LASER cuts the bone with minimal thermal damage and have precise control of bone cutting. Recent studies shows that laser facilitated flapless corticotomy is a useful procedure to speed up treatment time and it eliminates the necessity of invasive flap surgery.
Various studies have shown great success in accelerating tooth movement on use of low level laser therapy. An average increase in 30% rate of tooth movement and pain scores were also low with low intensity laser therapy. Animal experiments have shown that low-level laser can accelerate tooth movement. Furthermore, clinical trial attempts were made in which different intensities of laser were used and different results were obtained. In a split mouth study on canine retraction conducted by Salman and Ali on 15 Iraqi subjects using the erbium:yttrium aluminum garnet laser, the canines on the laser corticotomy side showed faster retraction than their controls.
Recently, a product by the name AcceleDent  has been introduced which makes use of the vibrations/micro-impulses to hasten tooth movement. This is a simple to use, hands free device which has a mouthpiece that is inserted around the existing braces and the activator is turned on for 20 min every day to generate small vibrations. It is a portable device that can be charged similar to any other electronic device. Research has shown that the tooth movement is accelerated by 106% during initial phase of treatment and up to 50% during subsequent phase of treatment, thus reducing the orthodontic treatment duration. However, as the system is newly introduced, further long-term research is required to prove its results.
Chemically produced PGE2 in human trials showed that the rate of distal retraction of canines was 1.6-fold faster than the control side. However, prostaglandin leads to a generalized increase in the inflammatory state and also causes root resorption. Research has shown that Vitamin D3 may be more effective in bone turnover rather than acceleration of tooth movement, as greater number of osteoblasts is seen on side where Vitamin D3 was injected. Vitamin D when injected in the periodontal ligament (PDL) increases the levels of lactate dehydrogenase and creatine phosphokinase enzymes. However, a recent prospective split mouth clinical trial carried out by Shetty et al. showed that the experimental teeth that received local injections of Vitamin D3 moved considerably slower than the matched control teeth. Locally, injected parathyroid hormone (PTH) was found to be more efficacious when compared to the systemically administered form and slow release application of PTH was seen to be more efficient than PTH in saline solution in causing acceleration of tooth movement in rats., Experiments on rats suggest significant effect of relaxin on tooth movement acceleration, however, similar studies on humans suggest exactly the opposite. Relaxin reduces PDL reorganization and mechanical strength of PDL, thereby it might contribute to reduction in the rate of relapse.,, All of these drugs have some or the other unwanted adverse effect. As of today, no drug exists that can safely accelerate orthodontic tooth movement.
| Conclusion|| |
Adults willing to undergo orthodontic therapy can thus be offered various options to shorten the treatment time. The surgical approach is the most clinically used with known predictable and stable results; however, it is highly invasive and costly. The patients who are not open to ideas involving such highly aggressive options should be offered lesser invasive techniques like piezocision which is considered the least invasive of all the surgical approaches. Newer techniques such as laser assisted flapless surgery may also be preferred due to its less invasive nature and good healing powers, however, significant amount of research is still required in this area. Recently introduced systems like AcceleDent are noninvasive and may become the primary option for tooth movement acceleration in the coming years.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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