IntroductionComplex malocclusions like severe rotationhas always possessed a serious setback toorthodontic treatment in terms of prolongedtreatment time. But with the development ofcorticotomy assisted orthodontics various newvistas have been opened up for enhancingorthodontic treatment. Reduced treatmenttime, increased alveolar volume and reducedroot resorption have weighed in overconventional non surgical procedures.
What is accelarated osteogenic orthodontics?• Accelerated osteogenic orthodontics is abrain child of an orthodontist and aperiodontist, Dr.Willian Wilcko andDr.Thomas Wilcko.William Wilcko Thomas Wilcko
• Corticotomy assisted orthodontics is a uniqueblend of orthodontic mechanics with alveolardecortication and alveolar augmentationprocedure. This technique is 3-4 times fasterthan conventional methods thereby bringingdown the treatment duration. These aresurgical interventions limited to corticalportion of alveolar bone.
What is regional acceleratory phenomenon?• Introduced by Frost in 1983.• Regional – demineralisation occurs at both the cutsite as well as adjacent bone.• Acceleratory - exagerated or intensified boneresponse in cuts that extends to the bone marrow.• Regional acceleratory phenomenon is a localresponse to noxious stimulus which describes aprocess by which tissue forms faster than normalregional regeneration process.
• Following surgical insult to cortical bone,regional acceleratory phenomenon increasesthe tissue reorganization and healing bytransient burst of localized hard and softtissue remodelling.• Initial phase results in increased cortical boneporosity because of increased osteoclasticactivity.• Calcium depletion and diminished bonedensities result in rapid tooth movement.
Accelerated osteogenic orthodontics surgicaltechnique.• AOO is an interdisciplinary technique whichrequires the expertise of an orthodontist andoral surgeon/periodontist.• Brackets and arch wires are placed at leastone week prior to surgery.• Surgery is performed under local anaesthesia.
•Full thickness flap wasraised labially and lingually.•Flaps are raised beyond theapices of the teeth to avoiddamaging the neurovascularcomplex.
Buccal and lingual corticotomy cuts andcortical bone perforations are madenear the malpositioned teeth using lowspeed round burs.
After bone activation,bone grafting materiallayered over the activated bone.
•Graft material can be bovine powder or 100% demineralised freezedried bone graft .•Quantity of bone graft depends on the quality of pre existing bone.•Graft is wet with clindamycin phosphate/ bacteriostatic water/platelet rich plasma of 5 mg/ml. this provides an antibiotic effectas well as medium for placement.
Flap is repositioned using non resorbablesuture material.
• Soon after flap repositioning orthodontic forceshould be applied.• Orthodontic adjustments should be madeevery 2 weeks interval.• The tooth movement that occurs at this stageis purely physiological and not byrepositioning the segments of bone.• Osteoclastic activity increases, temporaryintrabony osteopenia occurs as well as at thesame time decortication induces this state.
Case reportPatients age : 15 yrs.Sex : male.Patients chief complaint : patient complaints offorwardly placed upper front teeth.
• Diagnosis : Angles Class I malocclusionon a Class I skeletal base withorthognathic maxilla and mandible, withbimaxillary dento alveolar proclinationand protrusion, with single tooth crossbite in relation to 43, midline diastemaof 2 mm and disto buccal rotation of 33,overjet of 8 mm and overbite of 5 mm.
Treatment plan : Extraction of all firstpremolars.• Patient was bonded with 0.018 Rothpreadjusted edgewise appliance.• 0.016 coaxial wire was placed in both upperand lower arches for initial levelling andaligning.
•Over a period of 8 months we tried most of theconventional techniques to derotate canine.•Unfortunately non of them could give a proper result.•At that juncture we strated thinking about
•0.016 x 0.022 NiTi piggy back wire was fullyengaged into the canine bracket using ligaturetie on the day of surgery to apply a light andcontinous force.
• Elastic chain was also placed from the buttonplaced on the distal surface of canine to therigid 0.017x0.025 stain less steel base archwire with gingival off set.• Orthodontic adjustment was done in every 2weeks interval.
Conclusion• Corticotomy assisted orthodontics is aneffective and reliable technique to treat severemalocllusions to reduce the treatment time andincrease the treatment quality.• Reduced root resorption, increased alveolarvolume, reduced chair side time are the basicadvantages of this technique. However thisshould be carefully performed over the teethand surrounding tissues to avoid the risk ofdevitalization of the teeth and periodontaldamage.
• A long term follow up studies have to beperformed to evaluate the effects ofcorticotomy assisted orthodontics onretention and stability.