|Year : 2020 | Volume
| Issue : 1 | Page : 23-29
Fast track tooth movement: An amalgamation of periodontics and orthodontics
Aanchal Agrawal1, Gaurav Gaur2, Lokendra Singh Dagur1, Upendra Singh Bhadauria3, Karan Seth4, Siddharaj Parmar5
1 Department of Orthodontics and Dentofacial Orthopaedics, Jaipur Dental College, Jaipur, Rajasthan, India
2 Department of Oral and Maxillofacial Surgery, Eklavya Dental College, Jaipur, Rajasthan, India
3 Research Officer, National Oral Health Programe, AIIMS, New Delhi, India
4 Independent Researcher, Chandigarh, Punjab, India
5 Independent Researcher, Vapi, Gujarat, India
|Date of Submission||07-Feb-2020|
|Date of Decision||18-Feb-2020|
|Date of Acceptance||25-Feb-2020|
|Date of Web Publication||28-Jul-2020|
Dr. Aanchal Agrawal
133-A, Gom Defence Colony, Vaishali Nagar, Jaipur, Rajasthan
Source of Support: None, Conflict of Interest: None
The major concern in orthodontics is prolonged duration of time of treatment, which prompts the patients to either avoid orthodontic treatment or to seek other alternatives with compromised results. The long duration of orthodontic treatment has some other disadvantages also, such as high risk of caries, gingival recession, and root resorption. Hence, to overcome the long treatment time challenge the demand to find the most efficient means to accelerate the movement of tooth with minimal disadvantages has increased. Hence, this article is aimed to review the effective approaches in the movement of tooth and present the updated techniques in tooth movement. Numerous methods have been introduced by orthodontics to accelerate tooth movement are corticision, corticotomy, micro-osteoperforations/peizo puncture, and piezocision. One of the best surgical approaches is piezocision (corticotomy) technique minimally invasive and flapless procedure because it can give excellent aesthetic outcome including good periodontal tissue response. Prostaglandins, Vitamin D, and cytokines have also shown promising results. Considering the advantages and disadvantages of each method, furthermore, investigations are required to determine the best method to accelerate tooth movement.
Keywords: Accelerated orthodontics, piezocision, Wilckodontics
|How to cite this article:|
Agrawal A, Gaur G, Dagur LS, Bhadauria US, Seth K, Parmar S. Fast track tooth movement: An amalgamation of periodontics and orthodontics. Saint Int Dent J 2020;4:23-9
|How to cite this URL:|
Agrawal A, Gaur G, Dagur LS, Bhadauria US, Seth K, Parmar S. Fast track tooth movement: An amalgamation of periodontics and orthodontics. Saint Int Dent J [serial online] 2020 [cited 2021 Jan 21];4:23-9. Available from: https://www.sidj.org/text.asp?2020/4/1/23/291028
| Introduction|| |
The requirement to achieve a better smile by enhancement of dentofacial function and esthetic number of adult patients are striving for orthodontic treatment is increasing day by day but minimal treatment time is the prime concern for every adult patient. In the past years, “Orthodontics and dentofacial orthopaedics” has developed clinically and technically, like as modifications in designs of brackets and bands and using stimulation software assisting treatment planning. All these methods have increased the efficiency of the treatment but still the challenge remains for the orthodontist to decrease the time span of the treatment.
The first instance of accelerated orthodontics was introduced using a surgical technique in 1931 by Bichlmayr for the correction of severe maxillary protrusion. He removed wedges of bone for the retraction of anterior teeth. Kole in 1959 expanded on this corticotomy for space closure and crossbite correction. In 2001 Wilcko and Wilcko,, using the earlier concept of regional acceleratory phenomenon (RAP) by Frost, expanded on it and showed the transient demineralisation-remineralisation process of periodontally accelerated osteogenic orthodontics (PAOO), also called wilckodontics [Table 1].
Longer orthodontic treatment has disadvantages such as:
- Predisposition to dental carries,
- Poor oral hygiene,
- Gingival recession, and
- Root resorption.
To overcome all these factors and accelerate the tooth movement variety of attempts have been made clinically and preclinically.
Currently, accelerated orthodontic technique can be classified into the following types:
- Surgery-assisted accelerated orthodontics
- Drug-assisted accelerated orthodontics
- Physical and mechanical stimulation methods for accelerating tooth movement.
| Surgery-Assisted Accelerated Orthodontics|| |
In 1892 Bryan described the use of corticotomy in correcting malocclusion but in 1959 it was Kole who introduced alveolar corticotomy to treatmalocclusion.
Corticotomy procedures are based on the RAP and normal bone-healing mechanisms. There are three tissue engineering principles associated with the selective alveolar decortication technique. At first, the surgery initiates the local tissue repair of tissue assisted by the production of osteoprogenitor cells and osteoinductive agents. Second, low turnover tissues are replaced with high turnover tissues that are functionally normal, a reversible condition often referred to as osteopenia. Finally, high tissue turnover is promoted in a precise anatomic area next to the area of the desired tooth movement. The resulting tissues that form in the alveolus surrounding the area of desired tooth movement responds efficiently to biomechanical forces, and teeth move rapidly.,,,,
- Reduced treatment time
- Low rate of relapse
- Less root resorption due to the least resistance.
- Less acceptance by patience
- Postoperative pain, swelling, chances of infection necrosis
- Chances of damage to the local vital structures.
Corticotomy used in several tooth procedures such as:,,,,,,,
- Canine retraction
- Anterior tooth retraction
- Extrusion of impacted canine
- 3rd molar uprighting.
| Piezocision (Minimally Invasive and Flapless Procedure)|| |
It was first described by Dibart et al., in 2009, a minimally invasive procedure that includes micro incisions on the buccal gingival and piezoelectric knife is used to give osseous cuts thorough the buccal cortex and initiate the RAP without involving palatal or lingual cortex.
Piezocision is done 1-week after the placement of orthodontic appliances weather it may be removal or fixed. Vertical interproximal incision is given below the papilla through the periosteum till the cortical bone. A piezo knife is used, and a cortical alveolar incision is given through the gingival micro-opening to a depth of approximately 3 mm. When the corticotomies are finished, the areas requiring bone grafts are tunneled using a small periosteal elevator through the vertical incision followed by grafting and the incision is closed using 5-0 vicryl. Areas without grafting do not require suturing.
- Reduced treatment time than conventional corticotomy
- Minimally invasive with least postoperative complication
- When used in combination with bone grafting, it increases the scope of treatment including the correction of crowding without extraction
- Less chances of damage to the roots of tooth during corticotomy
- No postoperative swelling.,
| Wilckodontics|| |
Wilckodontics or PAOO or alveolar osteogenic orthodontics is a procedure including precise corticotomy, bone grafting followed by the application of orthodontic forces. Advantages of wilckodontics are as follows:
- Reduces treatment time
- Increases stability of tooth
- Prevents relapse of orthodontic tooth movement (OTM).
The technique of wilckodontics involves the removal of cortical bone small enough to initiate the local response known as RAP.
This rapid tooth movement was initially thought to be the movement of bony blocks after decortication. This was reported by Kole in 1959. In 2001, Wilcko et al. reported that rapid tooth movement was not the due to the movement of bony blocks but the demineralization and remineralization of the bone around the tooth. This healing process came to be known as RAP.
What is RAP?
- This RAP (based on bone healing pattern) as described by Frost in the year 1983, is an inflammatory process or a localized reaction to noxious stimuli, by which the tissue regenerates faster than the normal regional physiological process.
Main features of RAP are:
- Decreased regional bone density
- Accelerated bone turnover.
- Many studies have reported an increase in the activity of inflammatory markers such as chemokines and cytokines in response to orthodontic forces. In the recruitment of cytokines and osteoclast precursor cells as well as the differentiation into mature osteoclasts, chemokines play an important role, through the prostaglandin (PG) E2 pathway and the RANK/RANKL pathway. Therefore, by surgically irritating the bone, there is an infiltration of these factors leading to accelerate tooth movement
- Sebaoun et al. have shown histologically that selective alveolar decortication caused a spike in turnover of alveolar spongiosa. Surgery results in a transient and reversible increase in alveolar demineralization. This will result in osteopenia which enables rapid tooth movement through the collagenous soft tissue matrix of bone. As long as, tooth movement continues, there is RAP. But when the RAP ceases, the osteopenia disappears and the radiographic image of normal bone reappears. Then when OTM is completed, an environment is created that favors alveolar re-mineralization and more stability,,
- Simply stated, when bone is surgically abraded, a wound is developed and initiates a localized inflammatory response. Due to the presence of the inflammatory markers, osteoclasts migrate to the area and cause bone resorption. This effect, however, is temporary and lasts for about 4 months and the procedure needs to be repeated.
Wilckodontics is a combination of selective decortication with facilitated orthodontic treatment and alveolar augmentation which allows the teeth movement around 2–3 times further in 1/3–1/4th the time of traditional orthodontic treatment. PAOO or Wilckodontics has made adult orthodontics very easy and with reduced treatment period. PAOO avoid secondary effects of conventional orthodontic treatment such as root resorption, or other periodontal problems with better postorthodontic stability.
Wilckodontics is contraindicated in following
- Patients with severe periodontal problems
- Patients on long-term nonsteroidal anti-inflammatory drugs (NSAIDs) therapy as NSAIDs interfere with the PG hormone in the body and slow down the bone growth process which is vital to PAOO
- In cases where the bimaxillary protrusion is accompanied with gummy smile.
| Micro-Osteoperforations|| |
Propel, a device was introduced by Propel Orthodontics to reduce the invasive nature of surgical irritation of bone which used a process known as alveocentesis which literally translates to puncturing bone. The use of this device displayed the expression of inflammatory markers on OTM. This leads to increase in osteoclast activity and rate of tooth movement.
In 2013, Mani Alikhani et al. performed a study to investigate this procedure on humans. They used a Ni-Ti closed coil spring with a force of 100 g, anchored to a Temporary anchorage device (TAD) distal to second premolar, to distalize the maxillary canine after first premolar extraction. Gingival crevicular fluid (GCF) samples were collected before and after tooth movement from each subject to evaluate the level of inflammatory response. It was observed that this process leads to recruit osteoclast precursors and stimulate osteoclast differentiation by an increased in infiltration by inflammatory markers (cytokines and chemokines). Micro-osteoperforations (MOPs) increased the rate of canine retraction 2.3-fold compared to the control group. Patients reported mild discomfort locally.
- MOPs are an effective, comfortable, and safe procedure to accelerate tooth movement during orthodontic treatment
- MOPs could reduce orthodontic treatment time by 62%.
| Interseptal Alveolar Surgery|| |
Also known as distraction osteogenesis, interseptal alveolar surgery is divided into:
- Distraction of periodontal ligament (PDL) or
- Distraction of the dentoalveolar bone;
Both procedures result in rapid canine distraction. At the time of extraction of first premolar the interseptal bone is undermined approximately 1–1.5 mm in thickness surgically which will reduce the resistance on surgical site. This initial phase of tooth movement procedure is known as rapid canine distraction of PDL in which compact bone will replace by woven bone., Now, the retraction of canine will be done by intraoral devices and it has proved that it took 3 weeks to achieve 6–7 mm of full retraction in to the socket of previously extracted first premolar.
Numerous studies have shown accelerated tooth movement with no evidence of significant root resorption, ankyloses, and root fracture however few are contradictory resulting electrical vitality test of retracted canine as Liou reported 9 out of 26 teeth positive and in another study done by Sukurica have mentioned 7 out of 20 showed positive vitality after 6 months of retraction.
| Drugs|| |
A lot of drugs have been experimented to accelerate the tooth movement in orthodontic treatment. Mainly these include PGs, Vitamin D, misoprestrol, PGs are chemical messengers belonging to the family of hormones called eicosanoids. PGs when injected at the site of tooth movement intensify the bony remodelling process and thereby augment the rate of orthodontic treatment. PGs are the mediators of mechanical stress during orthodontic treatment, they stimulate the bone resorption, decreases collagen synthesis, and increase cyclic adenosine monophosphate. They also increase the number of osteoclasts and promoting the formation of ruffled borders, thus increasing the rate of bone resorption.
Vitamin D and its active metabolite, 1,25,2(OH)D3, together with parathyroid hormone (PTH) and calcitonin, regulate the amount of calcium and phosphorus levels. Vitamin D receptors have been demonstrated not only in osteoblasts but also in osteoclast precursors and in active osteoclasts. In 1988, Collins and Sinclair demonstrated that intraligamentary injections of Vitamin D metabolite, 1,25-dihydroxycholecalciferol, caused increase in the number of osteoclasts and amount of tooth movement during canine retraction with light forces. However, all of the drugs come with certain disadvantages such as injection of Vitamin D in PDL spaces causes increased levels of lactate dehydrogenase and creatine phosphokinase enzymes, PGs induce generalized inflammatory state. Till now, none of the drugs have been proved completely safe for the purpose of accelerating orthodontics.,
[TAG:2]Effect of Cytokines on Tooth Movement[/TAG:2]
High concentrations of cytokines found in gingival crevicular fluid such as interlukins (IL)-1, IL-2, IL-3, IL-6, IL-8, tumor necrosis factor-α, interferon-γ, and osteoclast differentiation factor play a vital role in bone remodeling; moreover IL-1 through its receptor stimulates osteoclastic function. Mechanical stress (tension side) increased the production of prostaglandin prostaglandinc E (PGE) and IL-1β in the PDLs. The first research were done on periodontal tissues of cats teeth where IL-1α and IL-1β were identified after the application of a tipping force. Osteoprotegerin (OPG) competes with RANKL in binding to osteoclast to inhibit osteoclastogenesis. The process of bone remodeling is a balance between (RANKL-RANK) system and OPG compound. RANKL gene introduced in the periodontal tissue of rats induced prolonged gene expression for the enhancement of tooth movements. Similarly, the transfer of OPG gene inhibited OTMs. It was also found that juvenile teeth move faster than adults, due to the lower amount of RANKL/OPG ratio in adult patients compared to juvenile patients. It was also found that patients with root resorption produced a large amount of RANKL in the compressed site.
| Prostaglandin Effect on Tooth Movement|| |
An inflammatory mediator and a paracrine hormone that acts on nearby cells PGs stimulate bone resorption by increasing the number of osteoclasts directly. Yamasaki, was among the first to investigate the effect of local administration of PG on rats and monkeys [Table 2]. The administration of exogenous PGE2 over an extended period caused the acceleration of tooth movements in rats. However, root resorption was very clearly related to the different concentrations and number of injections given. PGE2 in the presence of calcium also stabilizes root resorption while accelerating tooth movement. PGE2 has been studied in human trials with split-mouth experiments in the first premolar extraction cases where it was evident that distal retraction of canines was 1.6-fold faster than the control side.,
|Table 2: Biological approaches to enhance tooth movement (references done with chronological order)|
Click here to view
| Effect of Vitamin D3 on Tooth Movement|| |
1,25 dihydroxycholecalciferol is a hormonal form of Vitamin D and plays an important role in calcium homeostasis with calcitonin and PTH. Injected Vitamin D metabolite on the PDL of cats showed that Vitamin D had accelerated tooth movement at 60% more than the control group due to the increase of osteoclasts on the pressure site as detected histologically. A comparison between local injection of Vitamin D and PGEs showed that there is no significant difference in acceleration between the two groups. However, the number of osteoblasts on the pressure side which was injected by Vitamin D was greater than on the PGE2 side this indicating that Vitamin D may be more effective in bone turnover.
| Parathyroid Hormone Effect on Tooth Movement|| |
PTH has been shown to increase the rate of OTM. A study on rats showed that by continuous infusion of PTH (1–10 μg/100 g of body weight/day) implantation in the dorsocervical region, the molars moved 2–3-fold faster. Studies have shown that locally injected PTH induces local bone resorption. The development of application where the daily injection of PTH dissolved in gel medium allowed a slow release that keeps the local concentration of PTH for a long time caused 1.6-fold faster acceleration of teeth compared to daily injection of PTH dissolved in saline solution.,,
| Relaxin Effect on Tooth Movement|| |
Relaxin, a hormone, is suggested to help during childbirth by widening of the pubic ligaments in females. It is present in the cranial suture and PDL. It is known to remodel soft-tissue primarily. It increases the collagen in the tension site and decreases it in the compression site during orthodontic movement. The administration of human relaxin accelerates the early stages of OTM as seen in rat experiments. However, this has been widely contested. Studies showed that relaxin can reduce the level of PDL organization and mechanical strength of PDL and increase tooth mobility.In vitro studies were also performed to test the PDL mechanical strength and tooth mobility using tissue from additional 20 rats that had previously received the same relaxin treatment. The remodeling of PDL by relaxin might reduce the rate of relapse after orthodontic treatment. Recently, randomized clinical trials on humans were done by weekly injecting 50 μg of relaxin for 8 weeks. Tooth movement was measured weekly and no significant difference was found between the relaxin and the placebo control group. However, the mechanism of how relaxin accelerates tooth movement is not yet fully understood.
| Device-Assisted Treatment|| |
This technique includes direct electric currents, pulsed electromagnetic field, static magnetic field, resonance vibration, and low-level laser, which was mostly investigated and gave the most promising results. It has been found that applying vibrations for different duration per day accelerated tooth movements between 15% and 30% in animal experiments. Cyclical force device effect on tooth movement, we have also used this concept using the cyclical force device with patients and achieved 2–3 mm/month of tooth movement. The vibration rate was 20–30 Hz and used for 20 min/day. Further results needed to be investigated to clearly identify the range of Hertz that can be used in these experiments to get the maximum desired results.
| Direct Electric Current Effect on Tooth Movement|| |
The effect of electric current was tested by supplying direct piezoelectric current in the mechanically by Davidovitch et al. in the year 1980 stressed bone to the anode at the pressure site and cathode at the tension sites by generating local responses and acceleration of bone remodeling. These studies done through applying direct current were successful because electrodes were placed as close as possible to the moving tooth. Further development of the direct electric device and the biocatalytic fuel cells is needed to be done so that these can be tested clinically.
| Low-Level Laser Therapy|| |
Photobiomodulation or low-level laser therapy (LLLT) has a bio-stimulatory effect on bone regeneration after extraction and after fracture of the bone. Some very important studies on LLLT are as[19-22]
- Baxter and diamantopoulos-done study on tissue response of laser wave length and energy density
- Mester et al. stated the effective range of energy density in the 0.5–4 J/cm2 n start of a photobiological tissue reaction and in support of this Van Breugel et al. reported power density is an important factor to start biomodulation
- Van Gemert and Welch in blood less tissue maximum penetration of infrared laser can be 1 cm.
Laser light can accelerate tooth movement by affecting remodeling and by proliferating activities of osteoclast, osteoblast, and fibroblast. This mechanism is supported by production of adenosine triphosphate and activation of cytochrome C that low-energy laser irradiation enhanced the velocity of tooth movement via RANK/RANKL and the macrophage colony-stimulating factor and its receptor expression. In an experiment done on rat with Laser wavelength of 800nm and output power of 0.25mW have indicated for the stimulation of bone metabolism and rapid ossification for the acceleration of tooth movement. In another study done by Kau on 90 subjects (73 test subjects and 17 controls), there was 1.12-mm change per week in the test subjects versus 0.49 mm in the control group. Having said this, there are a lot of contradictory results related to the LLLT. Therefore, more experiments are needed to differentiate the optimum energy, wavelength, and the optimum duration for usage.,,,,
| Discussion|| |
In the present era of orthodontics variety of measures have been used to accelerate the tooth movement to reduce treatment time and achieve better esthetic results.
In the above review, a lot of methods have been discussed for accelerating tooth movement, viz., surgical and nonsurgical. Surgical methods have proven to give more promising results with actual reduction of time in treatment.
It was Kole who introduced corticotomy-assisted orthodontic treatment in 1959 based on Regional acceleratory phenomena and normal bone healing mechanism. Corticotomy-assisted orthodontics provided rapid movement of teeth with less resistance and reduced relapse rate.
With further modification and as need for minimal surgical intervention with better results piezocision proved to be more useful. Piezocision as described by Dibert et al., in 2009, a procedure including microincision to initiate an RAP without involving lingual or palatal cortex. Piezocision has micrometric and selective osteotomy cuts, so piezo knife has precise osteotomy without necrosis. Furthermore, it works on mineralized surface only sparing the blood supply and the soft tissue.,
Piezocision proved to be more precise due to its micromotions, minimally invasive and with no postoperative complications such as swelling and pain. Piezocision when used with grafts was more successful in correction of crowding without extraction.
With further advancement and research, Wilckodontics came which facilitated tooth movement 2–3 times further in 1/3–1/4 of conventional orthodontic treatment. Wilckodontics has not only reduced the treatment span but also provided better stability in postoperative phase as compared to conventional orthodontic treatment. Reduced treatment time in Wilckodontics is attributed to RAP without secondary effects such as root resorption, dehiscence and minimal invasion. It is contraindicated in cases of bimaxillary protrusion, patients on long-term NSAIDs and severe periodontal disease.
For reduction of treatment time of orthodontic treatment nonsurgical methods are also being used-mainly PGs, Vitamin D, and cytokines. These drugs either locally applied or injected have enhanced the rate of tooth movement but these therapies are still under research.
| Conclusion|| |
Although many approaches have been discovered or formulated by animal or human experiments, the need for continued research still persists. Although surgical methods are most satisfying in results and clinical studies, yet their invasive nature does weary the patient and sometimes the clinician from opting for most of the procedures. Although a present need for reducing treatment time lurks among all clinicians to obtain more satisfying and stable results with least harm to the biological structures, there is still scope for further development and research into these so as to allow for much less invasive and more practical and economic methods of accelerated tooth movement across the clinical spectrum.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Bichlmayr A. Surgical orthodontics and the behavior of the bone and the tips of the sausage after it. Dtsch Zahnaerztl Wschr 1931;34:835-42.
Wilcko W, Wilcko MT. Accelerating tooth movement: The case for corticotomy-induced orthodontics. Am J Orthod Dentofacial Orthop 2013;144:4-12.
Frost HM. The regional acceleratory phenomenon: A review. Henry Ford Hosp Med J 1983;31:3-9.
Dibart S, Sebaoun JD, Surmenian J. Piezocision: A minimally invasive, periodontally accelerated orthodontic tooth movement procedure. Compend Contin Educ Dent 2009;30:342-50.
Dibart S, Yee C, Surmenian J, Sebaoun JD, Baloul S, Goguet-Surmenian E, et al
. Tissue response during Piezocision-assisted tooth movement: A histological study in rats. Eur J Orthod 2014;36:457-64.
Köle H. Surgical operations on the alveolar ridge to correct occlusal abnormalities. Oral Surg Oral Med Oral Pathol 1959;12:277-88.
Hoogeveen EJ, Jansma J, Ren Y. Surgically facilitated orthodontic treatment: A systematic review. Am J Orthod Dentofacial Orthop 2014;145:S51-64.
Wilcko MT, Wilcko WM, Bissada NF. An evidence-based analysis of periodontally accelerated orthodontic and osteogenic techniques: A synthesis of scientific perspectives. Semin Orthod 2008;14:305-16.
Saito M, Saito S, Ngan PW, Shanfeld J, Davidovitch Z. Interleukin 1 beta and prostaglandin E are involved in the response of periodontal cells to mechanical stress in vivo
and in vitro
. Am J Orthod Dentofacial Orthop 1991;99:226-40.
Yamasaki K, Shibata Y, Fukuhara T. The effect of prostaglandins on experimental tooth movement in monkeys. J Dent Res 1982;61:1444-6.
Yamasaki K, Shibata Y, Imai S, Tani Y, Shibasaki Y, Fukuhara T. Clinical application of prostaglandin E1 (PGE1) upon orthodontic tooth movement. Am J Orthod 1984;85:508-18.
Leiker BJ, Nanda RS, Currier GF, Howes RI, Sinha PK. The effects of exogenous prostaglandins on orthodontic tooth movement in rats. Am J Orthod Dentofacial Orthop 1995;108:380-8.
Yamasaki K, Miura F, Suda T. Prostaglandin as a mediator of bone resorption induced by experimental tooth movement in rats. J Dent Res 1980;59:1635-42.
Seifi M, Eslami B, Saffar AS. The effect of prostaglandin E2 and calcium gluconate on orthodontic tooth movement and root resorption in rats. Eur J Orthod 2003;25:199-204.
Kanzaki H, Chiba M, Arai K, Takahashi I, Haruyama N, Nishimura M, et al
. Local RANKL gene transfer to the periodontal tissue accelerates orthodontic tooth movement. Gene Ther 2006;13:678-85.
Nishijima Y, Yamaguchi M, Kojima T, Aihara N, Nakajima R, Kasai K. Levels of RANKL and OPG in gingival crevicular fluid during orthodontic tooth movement and effect of compression force on releases from periodontal ligament cells in vitro
. Orthod Craniofac Res 2006;9:63-70.
Collins MK, Sinclair PM. The local use of vitamin D to increase the rate of orthodontic tooth movement. Am J Orthod Dentofacial Orthop 1988;94:278-84.
Kale S, Kocadereli I, Atilla P, Asan E. Comparison of the effects of 1,25 dihydroxycholecalciferol and prostaglandin E2 on orthodontic tooth movement. Am J Orthod Dentofacial Orthop 2004;125:607-14.
Soma S, Matsumoto S, Higuchi Y, Takano-Yamamoto T, Yamashita K, Kurisu K, Iwamoto M. Local and chronic application of PTH accelerates tooth movement in rats. J Dent Res 2000;79:1717-24.
Liu ZJ, King GJ, Gu GM, Shin JY, Stewart DR. Does human relaxin accelerate orthodontic tooth movement in rats? Ann N
Y Acad Sci 2005;1041:388-94.
Omidkhoda M, Radvar M, Azizi M, Hasanzadeh N. Piezopuncture-assisted canine distalization in orthodontic patients: Two case reports. J Dent (Shiraz) 2018;19:74-82.
McGorray SP, Dolce C, Kramer S, Stewart D, Wheeler TT. A randomized, placebo-controlled clinical trial on the effects of recombinant human relaxin on tooth movement and short-term stability. Am J Orthod Dentofacial Orthop 2012;141:196-203.
[Table 1], [Table 2]