Canine retraction /certified fixed orthodontic courses by Indian dental academy

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The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.

Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
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Canine retraction /certified fixed orthodontic courses by Indian dental academy

  1. 1. JOURNAL CLUB INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
  2. 2. CANINE RETRACTION BY FRICTIONLESS MECHANICS Presented by:- Dr sasikumar www.indiandentalacademy.com
  3. 3. INTRODUCTION • OVER THE YEARS ORTHODONTISTS HAVE INCREASINGLY SHOWN MORE INTEREST IN RETRACTING PERMANENT CUSPIDS. THIS DENTAL MOVEMENT IS NECESSARY IN SPACE CLOSURE OF THE ARCH FOR RESOLVING DIFFERENT ORTHODONTIC PROBLEMS www.indiandentalacademy.com
  4. 4. METHODS OF CANINE RETRACTION • FRICTIONAL MECHANICS • FRICTIONLESS MECHANICS www.indiandentalacademy.com
  5. 5. FRICTIONLESS MECHANICS • TEETH ARE MOVED WITHOUT THE BRACKETS SLIDING ALONG THE ARCH WIRE. RETRACTION IS ACCOMPLISHED WITH LOOPS OR SPRINGS,WHICH OFFER MORE CONTROLLED TOOTH MOVEMENT THAN SLIDING MECHANICS.THIS TECHNIQUE PROVIDES EFFICIENT SPACE CLOSURE WITH EXCELLENT FORCE CHARACTERISTICS www.indiandentalacademy.com
  6. 6. ADVANTAGES: • ABSENCE OF FRICTION BETWEEN THE BRACKET AND THE WIRE • THE FORCE LEVELS ARE EASIER TO EVALUATE CLINICALLY • THE MOMENT/FORCE RATIO OF THE CUSPID AND THE POSTERIOR SEGMENT IS PREDICTABLE AND CONTROLLABLE DURING RETRACTION www.indiandentalacademy.com
  7. 7. PRINCIPAL CHARACTERISTICS OF A CANINE RETRACTION SPRING • MOMENT TO FORCE RATIO (M/F) APPLIED AT THE BRACKET WHOSE VALUE DETERMINES THE POSITION OF THE CENTER OF ROTATION DURING THE ORTHODONTIC MOVEMENT (WHICH CONTROLS THE CENTER OF ROTATION ) www.indiandentalacademy.com
  8. 8. • . LOAD/DEFLECTION RATIO (F/D) OF THE SPRING (THE LEVEL OF FORCE PRODUCED BY THE SPRING PER ACTIVATION) (WHICH HELP TO MAINTAIN IDEAL FORCE LEVEL DURING ORTHODONTIC TOOTH MOVEMENT ) www.indiandentalacademy.com
  9. 9. • MAXIMUM STRENGTH (FMAX) -THE SPRING IS ABLE TO RELEASE WITHOUT PERMANENT DEFORMATION. www.indiandentalacademy.com
  10. 10. FORCES • HORIZONTAL FORCES • VERTICAL FORCES www.indiandentalacademy.com
  11. 11. HORIZONTAL FORCES • IT IS THE FORCE APPLIED FOR THE RETRACTION OF THE CANINE . • THE DISTAL FORCES ACTING ON THE ANTERIOR TEETH ALWAYS EQUAL TO THE MESIAL FORCES ACTING ON THE POSTERIOR TEETH www.indiandentalacademy.com
  12. 12. VERTICAL FORCES • THESE ARE INTRUSIVE/EXTRUSIVE FORCES ACTING ON THE ANTERIOR OR POSTERIOR TEETH • THESE FORCES ARE GENERATED FROM UNEQUAL ALPHA AND BETA MOMENTS OR BY PLACING THE THE LOOP OFFCENTER www.indiandentalacademy.com
  13. 13. • PLACING THE LOOP OFFCENTER TOWARDS THE CANINE WITH EQUAL ALPHA AND BETA MOMENT EXTRUDES ANTERIOR AND INTRUDES THE POSTERIORS. • IF THE LOOP IS TOWARDS THE POSTERIORS THEY EXTRUDE POSTERIOR S AND INTRUDE THE ANTERIORS www.indiandentalacademy.com
  14. 14. MOMENT • WHEN A RETRACTION SPRING IS USED TWO MOMENTS ARE CREATED . • THE ALPHA MOMENT –PRODUCES DISTAL ROOT MOVEMENT OF THE ANTERIOR TEETH • THE BETA MOMENT -PRODUCES MESIAL ROOT MOMENT OF THE POSTERIOR TEETH www.indiandentalacademy.com
  15. 15. • IF ALPHA AND BETA MOMENT ARE UNEQUAL VERTICAL FORCES ARE GENERATED • IN CASE OF CENTRAL BEND ALPHA AND BETA MOMENT ARE EQUAL,THEN BOTH ANTERIOR AND POSTERIOR SEGMENTS MOVE TO THE SAME EXTEND www.indiandentalacademy.com
  16. 16. • WHEN ALPHA MOMENT IS GREATER THAN BETA MOMENT, POSTERIOR PROTRACTION IS ACHIEVED . • IF THE BETA MOMENT IS GREATER ANTERIORS ARE RETRACTED www.indiandentalacademy.com
  17. 17. • DIFFERENTIAL MOMENT OF THE ANTERIOR AND POSTERIOR SEGMENTS CAN BE ACHIEVED BY OFFCENTERING THE BENDS www.indiandentalacademy.com
  18. 18. • IF THE OFFCENTER IS TOWARDS THE ANTERIOR IT ENHANCES ANTERIOR ANCHORAGE • IF THE OFFCENTER IS TOWARDS THE POSTERIOR THEN POSTERIOR ANCHORAGE IS ENHANCED www.indiandentalacademy.com
  19. 19. • FOR ANTERIOR RETRACTION,THE RETRACTION LOOP SHOULD BE PLACED CLOSER TO THE CANINE TO DELIVER GREATER MOMENT TO FORCE RATIO CONSTANTLY • A GABLE BEND ADDED NEAR THE MOLAR WILL PRODUCE A LARGE BETA MOMENT THUS INCREASING THE POSTERIOR ANCHORAGE www.indiandentalacademy.com
  20. 20. • AS THE BETA MOMENT BECOMES RELATIVELY GREATER THERE IS GREATER INTRUSIVE FORCE ON THE ANTERIOR TEETH AND EXTRUSIVE FORCE ON THE POSTERIOR TEETH • THE M/F RATIO INCREASES AS THE SPRING DEACTIVATES IT SHOULD NOT BE REACTIVATED TOO OFTEN www.indiandentalacademy.com
  21. 21. MOMENT TO FORCE RATIO • CONTROLLED ROOT POSITION DURING MOVEMENT REQUIRES BOTH,FORCE TO MOVE THE TOOTH AND A COUPLE TO PRODUCE THE NECESSARY COUNTERBALANCING MOMENT www.indiandentalacademy.com
  22. 22. THE TYPE OF MOVEMENT • DICTATED BY THE MOMENT TO FORCE RATIO GENERATED BY THE APPLIANCE AT THE ATTACHMENTS. • MOMENT TO FORCE RATIO OF 7:1 RESULTS IN CONTROLLED TIPPING • 10:1 RESULTS IN BODILY MOVEMENT • 13:1 RESULTS IN ROOT TORQUE www.indiandentalacademy.com
  23. 23. METHODS TO INCREASE MOMENT TO FORCE RATIO • THE LOOP CAN BE MADE AS LONG AS POSSIBLE IN APICAL DIRECTION • INCREASE THE AMOUNT OF WIRE PLACED GINGIVALLY AT THE TOP OF THE LOOP www.indiandentalacademy.com
  24. 24. LOAD DEFLECTION RATE • IT REPRESENTS THE RATE OF FORCE DECAY • THE LOW LOAD DEFLECTION RATE IS IMPORTANT IN A SPRING SINCE IT ENABLES TO DELIVER OPTIMAL MAGNITUDE OF FORCE FOR A LARGE ACTIVATION • LOAD DEFLECTION OF A SPRING DEPENDS ON ITS MODULUS OF ELASTICITY ,CROSS SECTION OF THE WIRE USED AND THE DESIGN OF THE SPRING www.indiandentalacademy.com
  25. 25. OPTIMAL LEVELS OF FORCE • NIKOLAI HAS DEFINED OPTIMUM ORTHODONTIC FORCE AS THAT WHICH PRODUCES A MAXIMUM OF DESIRABLE BIOLOGIC RESPONSE WITH MINIMUM TISSUE DAMAGE,RESULTING IN RAPID TOOTH MOVEMENT WITH LITTLE OR NO CLINICAL DISCOMFORT www.indiandentalacademy.com
  26. 26. • SMITH SUGGESTS A FORCE OF 150- 200GMS • REITAN-250GMS • PROFIT -100GMS www.indiandentalacademy.com
  27. 27. SPRINGS BEST SUITED FOR CANINE RETRACTION • T-LOOP • PG SPRING • DRUM SPRING www.indiandentalacademy.com
  28. 28. PG CANINE RETRACTION SPRING www.indiandentalacademy.com
  29. 29. • INTRODUCED IN 1985 BY POUL GJESSING • IT IS CONSTRUCTED IN THE READILY AVAILABLE 0.016"X0.022" STAINLESS STEEL WIRE AND CAN BE EASILY PLACED IN THE ROUTINELY USED 0.018" BRACKETS www.indiandentalacademy.com
  30. 30. CONSTRUCTION : • THE PG SPRING IS MADE IN0.016"X.022" STAINLESS STEEL RECTANGULAR WIRE. • IT HAS GINGIVALLY DIRECTED OVERLAPPING DOUBLE HELICES, OVOID IN SHAPE,10MM IN HEIGHT AND 5.5MM AT ITS WIDEST PART • IT HAS A SMALL OCCLUSAL HELIX 2MM IN DIAMETER. www.indiandentalacademy.com
  31. 31. • THE SMALLER END OFTHE WIRE IS CONTINUOUS WITH THE OCCLUSAL HELIX. • THIS PORTION IS THE CANINE PART AND WOULD FIT INTO THE CANINE BRACKET. AS IT COMES OUT OF THE OCCLUSAL HELIX, IT IS GIVEN A 15° GINGIVAL TURN. www.indiandentalacademy.com
  32. 32. PG CANINE RETRACTION SPRING Anti rotation bend35º Anti tip bend Beta bend 15º 12º 30º Occlusal loop Apical loop 2 mm 10 mm5.5 mm 16″X22″ STAINLESS STEEL 60° www.indiandentalacademy.com
  33. 33. • THE LONGER ARM OF THE WIRE IS THE ONE WHICH IS MEANT FOR ENGAGING THE PREMOLAR BRACKET AND THE MOLAR TUBE; • THIS POSTERIOR MOLAR ARM AS IT EXITS FROM THE DOUBLE OVOID LOOPS IS TURNED GINGIVALLY SUCH THAT THE WIRE MAKES AN ANGLE OF 12° TILL APPROXIMATELY THE SECOND PREMOLAR BRACKET AND THEN TURNED UP AT AN INCREASED TOTAL ANGULATION OF 30° www.indiandentalacademy.com
  34. 34. • THIS PORTION IS ALSO GIVEN AN ANTI-ROTATION BEND OF 60° TOWARDS THE CANINE TOOTH AND THEN THIS BEND AFTER TRAVERSING THE WIDTH OF THE SPRING IS CURVED BACK IN AN EXACTLY OPPOSITE DIRECTION OF THE INITIAL BEND DECREASING THIS TO A FINAL 35° www.indiandentalacademy.com
  35. 35. PLACEMENT • THE ANTERIOR END EMERGING OUT FROM THE SMALLER HELIX IS PLACED AS CLOSE AS POSSIBLE TO THE CANINE BRACKET AND THE FRONT END IS CHINCHED. • THE POSTERIOR END IS PLACED INTO THE SECOND PREMOLAR BRACKET AND THEN INTO THE 1ST MOLAR TUBE. www.indiandentalacademy.com
  36. 36. www.indiandentalacademy.com
  37. 37. ACTIVATION • THE SPRING IS PULLED BACK TILL THE DOUBLE OVOID GINGIVAL LOOPS OPEN BY 1MM AND CHINCHED BACK. • THIS GIVES AN APPROXIMATE FORCE OF 160 GRAMS. www.indiandentalacademy.com
  38. 38. SPACE CLOSURE • ON AVERAGE, 1.2 MM OF SPACE CLOSURE IS OBTAINED WITH THIS ACTIVATION IN FOUR WEEKS. • DURING THIS PERIOD THE HORIZONTAL FORCE DECREASES FROM 100 GMS TO 40 GMS • THE INTRUSIVE VERTICAL FORCE ON THE CANINE INCREASES UP TO 12 GMS. www.indiandentalacademy.com
  39. 39. • AN INITIAL HORIZONTAL FORCE OF 100 GM GENERATES AN M/F RATIO OF 9 MM AT THE POINT OF THE APPLIED FORCE. • THE INITIAL CANINE MOVEMENT IS THEREFORE A CONTROLLED TIPPING. www.indiandentalacademy.com
  40. 40. AFTER ONLY 0.3 MM OF DEACTIVATION OF THE SPRING • THE M/F RATIO INCREASES TO 10-11 , THUS PRODUCING TRANSLATION. www.indiandentalacademy.com
  41. 41. WHEN THE SPRING IS COMPLETELY DEACTIVATED • THE M/F RATIO IS 18 MM. THIS VALUE PRODUCES UPRIGHTING OF THE CANINE ROOT THAT COMPENSATES FOR THE INITIAL CONTROLLED TIPPING.. www.indiandentalacademy.com
  42. 42. • BODILY MOVEMENT OF THE CANINE IS THEREFORE OBTAINED BY A COMBINATION OF CONTROLLED TIPPING, FOLLOWED BY TRANSLATION AND UPRIGHTING www.indiandentalacademy.com
  43. 43. DRUM SPRINGS www.indiandentalacademy.com
  44. 44. • Introduced by- Dr M.Ali Darendeliler Mr Halux Darendeliler Developed in 1992 First published in E.J.O-1997 www.indiandentalacademy.com
  45. 45. APPLIANCE DESIGN • It consists of 4 parts -Constant force spring(CFS) with a hook -Drum -Spring box(SB) -Central pin soldered to molar band(CW) www.indiandentalacademy.com
  46. 46. www.indiandentalacademy.com
  47. 47. PLACEMENT AND ACTIVATION • Assembled and mounted on the molar band • Activated by pulling the end of the spring and engaging the hook on canine bracket www.indiandentalacademy.com
  48. 48. www.indiandentalacademy.com
  49. 49. • The amount of activation does not influence the amount of force applied • The force is constant and contineous • Usually 50 gms www.indiandentalacademy.com
  50. 50. RATE OF CANINE RETRACTION • 1.975+/- 0.615 mm of distal movement of canine is obtained in 4 weeks • Due to the mild force the M/F ratio is always constant at 10-11 ,which results in translation of canine www.indiandentalacademy.com
  51. 51. ADVANTAGE OF DRUM SPRING • No reactivation is necessary • It doesn’t require patient co- operation • Less chair side time • It produces constant and contineus force www.indiandentalacademy.com
  52. 52. REFERENCE www.indiandentalacademy.com
  53. 53. For more details please visit www.indiandentalacademy.com www.indiandentalacademy.com

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