Accelerated orthodontic tooth movement
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Transcript of Accelerated orthodontic tooth movement
Accelerated Orthodontic Tooth Movement: In Light of Evidence
Presenter: Dr. Aisha Khoja Supervisors: Dr. Fida
Dr. Attiya
Biomechanical approach
Physiological/mechanical approach
Pharmacological approach
Surgical-assisted approach
Surgery-simulated approach
POSSIBLE APPROACHES
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• No steel/elastomeric ligatures• Frictional force of ligatures ( O configuration)= 50 g• Reduced friction- especially passive design• Less force required for tooth movement• More physiological in terms of PDL vascular supply• More alveolar bone generation, greater expansion, less
proclination of anterior teeth, less need for extractions
Kapur et al: • Friction per bracket with Ni-Ti archwires-41g under conventional
ligation and 15g with Damon system• For SS wires: 61g (conventional); 3.6g (self ligating)
BIOMECHANICAL APPROACHSelf Ligating Bracket System
• Despite low friction, do not perform faster alignment/ space closure
• They are narrower than conventional brackets- effect of binding due to tipping is greater- increased resistance
• Short chair side time and less incisor proclination (1.5 degree)
Self Ligating Brackets- Current Evidence
BIOMECHANICAL APPROACH
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1.Chen SS et al. Systemic review of self ligating brackets. Am J Orthod Dentofacial Orthop.2010;137:726e1:726e18
2. Fleming PS, Johal A. Self ligating brackets in orthodontics. A systemic review. Angle Orthod.2010;80:575-84
Beeson et al & Davidovitch et al:• Direct current : 7 volts & 15 microamperes• Anode : pressure side; Cathode: tension side• Degree of bone formation and resorption at electrically treated
pressure & tension side was higher• Increase osteoblasts, PDL cells, osteoclasts
Mechanism: • Direct current generate local response to increase AB turnover
Disadvantages:• The device and battery providing electric current were bulky
1. Direct Electric Current Stimulation: Evidence
PHYSIOLOGICAL/ MECHANICAL APPROACH
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Beesan DC, Jhonston LE, Wisotzky J. Effect of constant currents on orthodontic tooth movement in cat. J Dent Res 1975;54:251-54
Davidovitch Z et al. Electric currents, bone remodelling and orthodontic tooth movment. Am J Orthod.1980;77:33-47
• Used clinically (2009)• It utilizes glucose as a fuel and enzymes as catalyst• Placed on the gingiva near the alveolar bone • Small size /minimal tissue injury
Disadvantage:• Short life time• Poor power density
Enzymatic Micro battery
PHYSIOLOGICAL/ MECHANICAL APPROACH
• Electric potentials can be created by applying force to a tooth resulting in bending of bone and generation of piezoelectric charges
• The charges are created when stress is applied and released • Vibration could be used to apply and release forces at rapid rate• AcceleDent vibratory system : High frequency vibration (30Hz) for
20 min/day
Mechanism:• Stimulate cell proliferation and maturation to allow faster bone
remodeling
Endogenous Piezoelectric stimulation
PHYSIOLOGICAL/ MECHANICAL APPROACH
• Prospective RCT: 45 patient , Random allocation for use of AcceleDent appliance
• NiTi coil spring was attached from canine and distally to TSAD• Distance checked b/w TSAD and distal of canine bracket – every 4 wks• 39 completed the trial and reported 38% (0.29mm/wk) faster tooth
movement compared to control (0.21mm/wk)
Discussion:• Lack of blinding & measurement method may affect the outcome• TSAD can drift under orthodontic loading-1.5mm• Vibration may results in accelerated drift of TSAD
Conclusion:Future research needed
Endogenous Piezoelectric stimulation: Evidence
PHYSIOLOGICAL/ MECHANICAL APPROACH
AcceleDent website.http//accledent.com/images/uploads/AcceleDent + increases+the Rate of Orthodontic tooth movement Results of a RCT Final for Print November 14 2011.pdf Accessed 20 May 2012
• Gallium-aluminium-arsenide Irradiation• Wavelength: 630-860nm energy , energy 4.5-6 J/cm2• Minimally invasive, simple and safe to apply
Mechanism:• Increase in ATP at localized site - induce cells to undergo a remodeling
process due to an elevated metabolic activity• Increase in vascular activity contribute to rapid turnover of bone
Evidence:• Controversial• Few studies reported positive result, few no effect and some reported
retarded tooth movement
Low-Level Laser Therapy: Evidence
PHYSIOLOGICAL/ MECHANICAL APPROACH
Youssef M et al. Low energy laser irradiation therapy during orthodontic tooth movement. A preliminary stud. Lasers Med Sci 2008;23:27-33
Limpanichkul et al. Effects of low laser therapy on rate of orthodontic tooth movement. Orthod Craniofac Res. 2006;9:38-43
• Light with 800-850nm wavelength (just above the visible light spectrum) penetrates cheeks and soft tissues over AB
• 97% light lost , 3% excite intracellular enzymes and increase cellular activity in PDL and bone
• Increase blood flow and may enhance tooth movement
Advantage: • Can be adjusted to apply light to only anterior teeth, whole arch or
posterior teeth
LLL therapy: Photo-biomodulation (Biolux)
PHYSIOLOGICAL/ MECHANICAL APPROACH
• Corticosteroids
• PG’s
• Growth Hormone
• Parathyroid hormone
• Active form of Vitamin D
• Relaxin
PHARMACOLOGIC APPROACH
Mechanism:• PGE2 – an important mediator of bone remodeling under
mechanical force (increase cAMP & cGMP)
Yamaseki &Harell et al: • Experiment on animal model found application of orthodontic force
– increase in PG’s synthesis- stimulate osteoclastic bone resorption
• Injections of PGE1 and PGE2 into gingival tissues near first molar – increase rate of tooth movement
Prostglandins: Evidence
PHARMACOLOGIC APPROACH
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Yamaseki K et al. Prostaglandin as a mediator of bone resoprtion induced by experimental tooth movement in monkeys. J Dent Res. 1982;61:1444-1446
• Following LA, 0.1 ml of a 0.01% PGE1 solution in saline was injected submucosally at pressure side
• Rate of canine retraction- 1.6 fold increase
Disadvantages:• Injection were repeated at weakly intervals• Severe pain after injections
Protaglandins: Clinical trials
PHARMACOLOGIC APPROACH
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Speilmann T et al. Acceleration of orthodontically induced tooth movement through the local application of prostaglandin (PGE1). Schweiz Monatsschr Zahnmed 1989;99:162-165
• Insulin family of structurally related hormone• Produced during pregnancy
Mechanism: • Increase rate of degradation of extracellular fibrous C.T (stimulate
collagenase)• Increase bone resorption via increase in TNF and IL-1B secretion
Relaxin
PHARMACOLOGICAL APPROACH
Kristiansson P et al. Does human relaxin-2 affect peripheral blood mononuclear cells to increase inflammatory mediators in pathological bone loss?.Ann N Y Acad Sci.2005;1041:317-9
Stewart Dr et al. Use of Relaxin in orthodontics. Ann N Y Ascad Sci.2005 1041:379-387
• Vitamin D and PTH regulate the amount of calcium and phosphorus levels
• Vitamin D receptors – present on osteoblasts but also in osteoclast precursors and in active osteoclasts
Collins and Sinclair et al (1988)• Intraligamentary injections of vitamin D metabolite- increase in
the number of osteoclasts and amount of tooth movement during canine retraction with light forces
• Stimulatory action of vitamin D on osteoblasts can help stabilize orthodontic tooth movement.
Vitamin D ( 1,25 Dihydroxycholecalciferol)
PHARMACOLOGICAL APPROACH
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• Rapid canine retraction through distraction of the PDL
• Rapid canine retraction through distraction of dento-alveolus
• Corticotomy assisted rapid tooth movement
• Corticision/Peizocision
SURGICAL-ASSISTED APPROACH
Mechanism:• Incorporation of a surgical procedure on interseptal bone distal to
canine the time of extraction of first premolar, resistance is reduced
• Rapid canine retraction through distraction (stretching) of PDL• This approach is based on distraction osteogenesis• Pressure side: Canine-interseptal bone complex transported
distally inside the socket • Tension side: PDL distraction leading to osteogenesis
1.Rapid canine retraction via PDL distraction
SURGICAL-ASSISTED APPROACH
Rapid canine retraction through distraction of PDL
Procedure• At the time of extraction of
1st pm, socket is deepened to the same depth as canine with a 4mm round carbide bur
• 1mm carbide fissure bur- to make two vertical grooves, running from socket bottom to the alveolar crest, on the MB and ML corners
• These grooves are joined obliquely toward the base of interseptal bone
Liou EJ, Haung CS. Rapid canine retraction through distraction of periodontal ligament. Am J Orthod Dentofacial Orthop. 1998;114: 372-383
Technique:• Mucoperiosteal flap reflected• Cortical holes made in alveolar bone from canine to 2nd pm curving
apically to pass 3-5mm from apex• Connect the holes with tapering fissure• First premolar is extracted and buccal bone removed• Large osteotomes are used to mobilize the whole segment• Distraction : after 3 days of surgery• Activation of distractor: twice/day in morning and evening• 0.8mm/day• Can also be used to bring ankylosed tooth into positionDisadvantage:• Aggressive and complicated
Rapid canine retraction through dento-alveolar distraction
SURGICAL-ASSISTED APPROACH
Kisniscu RS et al. Dentoalveolar distraction osteogenesis for rapid canine retraction. J Oral Maxillfac Surgery 2002. 60:389-394
• Local injury to the alveolar process reduces resistance to tooth movement and generate RAP
• First described in 1892 (fitzpatrick Barry)
Indications:• Resolve crowding and shorten treatment time• Accelerate canine retraction• Enhance post-orthodontic stability• Facilitate eruption of impacted teeth• Molar intrusion and open bite correction• Molar distalization
Kole’s technique: • Flap raised, vertical cuts facially and lingually between and under teeth
that did not penetrate all the way (only cortex)• Reduce resistance enhances en bloc movement of entire alveolar
segment
Corticotomy assisted orthodontic tooth movement
SURGICAL-ASSISTED APPROACH
• Accelerated osteogenic orthdontics (AOO) /periodontally accelerated osteogenic orthodontics
Technique:• Full thickness flaps are reflected carefully beyond the apices to
allow decortication around apices• Corticotomy cuts are made in the form of lines and dots• Small circular depressions were placed in facial surface of bone
over maxillary anterior teeth• Bio-absorbable graft is placed (demineralized freeze dried bone)• Tooth movement- should be started after a weak • Tooth movement should be completed within 3-4 months
Advantages of graft:• Reduces bone dehiscence/ fenestrations especially when lower incisors are advanced• Good healing of alveolar bone
Wilcodontics
SURGICAL-ASSISTED APPROACH
Micr0perforation:• Screws placed in gingiva b/w interproximal AB and removed• Enough to accelerate RAP
Piezocision:Minimally invasive flapless procedure combining microincisions, peizoelectric incisions & selective tunneling that allows for hard and soft tissue grafting
Advantages:• Minimally discomfort• Enhanced periodontium (added grafting)
Modified corticotomy
SURGICAL-ASSISTED APPROACH
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• Minimal surgical intervention• No flap is raised, No tunneling of hard or soft tissue graft not given
Indications:• To resolve anterior crowding• Anterior open bite
Technique:• Insert the surgical blade interproximally and parallel to occlusal plane 2-3
mm apical from the tip of the papilla • Tap blade with a mallet to a depth of approximately 8mm• Change the angle of the blade to approximately 45 degrees apically and tap
the blade to incise to a depth of 10mm to 12mm• The goal is to cut the cancellous bone between the roots to 50% to 75% of the
root length• Apply orthodontic forces immediately• See the patient every two weeks; forcibly mobilizing the teeth to induce
minor trauma to extend the effect.
Corticision
SURGICAL-ASSISTED APPROACH
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• Recent advancement: surgical blade is replaced by piezoelectric puncture
• Punctures rather than incisions penetrate gingiva, cortical bone, cancellous bone
Advantages:• Patient friendly• Less discomfort
• Evidence still needs further investigation
Corticision
SURGICAL-ASSISTED APPROACH
Park YG. Patient friendly orthodontics to accelerate tooth movement. Presented at the 23rd Annual conference of Taiwan Association of orthodontics. 2011. Taichung, Taiwan.
• Autologous platelet rich plasma can simulate the effects induced by bone surgery
• Platelets contain growth factors PDGF,TGF, EGF’s and other components that regulate and stimulate wound healing and amplify osteogenesis
Technique:• 0.9ml of LA injected in the labial and lingual mucosa of anterior teeth• 0.7ml of PRP injected in labial and lingual attached gingiva from
canine to canine (immediately after bonding)• Acetaminophen given to control post-injection pain• The rate of orthodontic alignment was faster than compared to
controls
SURGERY SIMULATED APPROACHSubmucosal Injections of PRP
Liou EJ et al. Submucosal injection of platelet rich plasma accelerates orthodontic tooth movement. Am J Orthod Dentofacial Orthop (in press).
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