Endodontic motors and rotary files

endodontic

1. Endodontic MOTORs , apex locator & nIti ROTARY FILES R O O T S T R A I N I N G C E N T E R KHARTOUM SUDAN Dr. Abdalazim Badraldin Sudanese Dental Center N ovember 2017

2. R O O T S T R A I N I N G C E N T E R KHARTOUM SUDAN

3. Endodontic Instruments Roots Training Center Khartoum Sudan

4. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Why Rotary Endodontic Istrumentation The two primary goals for root canal instrumentation are: 1. To provide a biological environment that is conducive to healing 2 . To provide a canal shape that is conformable to sealing . John T. McSpadden

5. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Why Rotary Endodontic Istrumentation Rotary I nstrumentation V/S Hand instrumentation -- Ability to collect and remove debris from the canal system -- Mechanical rotation provides a more constant movement inside the canal respecting and following the canal anatomy reducing the incidence of ledging , perforation or canal transpotation -- Less time

6. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Endodontic Rotary Files The greatest innovation in the manufacturing of endodontic rotary files in twentieth century ( 1960) Why Nickel – Titanium ( NiTi) Files NiTi V/S SS -- NiTi endodontic rotary files are entirely fabricated by machining process in contrast to twisting process of stainless steel files -- The widespread popularity of nickel-titanium ( NiTi ) rotary instruments arises from the relatively low elastic modulus of the nickel ­ titanium alloy, which permits use of these instruments in curved root canals that would present considerable difficulty for stainless steel instruments . -- The NiTi file comes back to its original straight form without showing any sign of lasting deformation . This is called shape memory.

7. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Endodontic Rotary Files Why Nickel – Titanium ( Nitti) Files NiTi V/S SS -- The ability of resisting stress without permanent deformation and going back to the initial lattice form is called super elasticity -- Super-elasticity and shape memory of NiTi alloy is because of phase transformation in their crystal structure. The alloy exists in two crystallographic forms i.e. parent Austenitic phase which is stronger and stable than the daughter Martensitic phase. On heating the alloy undergoes transformation from the Austenitic,stronger and stable phase to the Martensitic phase weaker phase , and on cooling it reverts back to Austenitic phase. A similar phase change occurs when the alloy is stressed during root canal treatment. On release of stress , the structure reverts back to Austenite. Austenite  Martensite  Austenite

8. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Endodontic Rotary Files Why Nickel – Titanium ( Nitti) Files NiTi V/S SS -- Cutting efficiency of NiTinol is only 60% than that of matching S.S. file. -- NiTi Does not give any signs of fatigue before they fracture. -- More expensive

9. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files 1)M-wire NiTi – Developed by Dentsply Tulsa Dental Specialties (Tulsa, OK, USA) Advantage: This material has greater flexibility and an increased resistance to cyclic fatigue when compared to traditional NiTi alloys 2) R-phase NiTi – Developed by SybronEndo (Orange, CA, USA) Advantage: Files have reduced stiffness and more fracture resistance compared to standard NiTi files. 3 ) Controlled-Memory (CM) NiTi Advantage: Files have superior cyclic fatigue resistance and increased torque strength over traditional NiTi files. Advances in Nickel-Titanium Metallurgy

10. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files Standardization of Endodontic Files Original recommendation by I ngle for standardized instruments INSTRUMENT DIAMETER AND TAPER Cutting blades 16 mm in length 2 % Taper . The diameter of the instrument at tip (D1) is determined by size in hundredths of millimeters. Diameter 2 (D2) is uniformly 0.32 mm greater than D1. Length- 21, 25, 31 mm.

11. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files Standardization of Endodontic Files Two modifications were made in Ingle’s original proposed recommendation - additional measurement at D3 , 3 mm from tip/ D1 , and specification for shapes of the tip : 75 degrees, ± 15 degrees .

12. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files Component of NiTi Rotary Files Taper It is expressed as the amount of file diameter increases each millimeter along its working surface from the tip towards the file handle. SIGNIFICANCE : The ability to determine cross-sectional diameter at a given point on a file can help the clinician to determine the file size in the point of curvature and the relative stress being placed on the instrument .

13. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files Component of NiTi Rotary Files

14. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files Component of NiTi Rotary Files Core It is the cylindrical center part of the file having its circumference outlined and bordered by the depth of the flutes. Significance :The flexibility and resistance to torsion is partially determined by the core diameter.

15. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files Component of NiTi Rotary Files Flute It is the groove in the working surface used to collect soft tissue and dentin chips removed from the walls of the canal. The effectiveness of the flute depends on its depth, width, configuration, and surface finish . A progressively larger distance between flute space and blade is required so as to avoid any compaction of debris and also provides an effective channel for its removal .

16. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files Component of NiTi Rotary Files Cutting edge: -- The surface with the greatest diameter -- The blade of the file. Significance : The cutting edge forms and deflects chips from the wall of the canal and cut or snags soft tissue. Its effectiveness depends on its angle of incidence and sharpness.

17. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files Component of NiTi Rotary Files Land or Marginal width The surface that projects axially from the central axis as far as the cutting edge between the flutes. Functions : -Prevents screwing in of the file - Supports the cutting edge - Limits the depth of cut Maintains the file in the Centre of root canal Relief Area A reduce surface area of the land Function reduce friction resistance

18. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files Component of NiTi Rotary Files Helix Angle The angle formed by the cutting edge with the long axis of the file. Helps in removing debris collected in the flute from the canal

19. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files Component of NiTi Rotary Files PITCH The pitch of the file is the distance between a point on the leading edge and the corresponding point on the adjacent leading edge . The number of the flute per unit length The smaller the pitch the shorter the distance between corresponding points more spirals the file will have greater the helix angle Most files have a variable pitch, that changes along the working surface. The result of a constant pitch and constant helical angles is a “thread-in” or “sucking down” of file within the canal .

20. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files Component of NiTi Rotary Files Rake Angle : is the angle formed by the leading edge and the radius of the file when the file is sectioned perpendicular to its long axis. If the angle formed by the leading edge and the surface to be cut is acute, the rake angle is said to be negative or scraping Most conventional endodontic files utilize a negative or “substantially neutral” rake angle. NEGATIVE RAKE ANGLE PROTAPER

21. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files Component of NiTi Rotary Files Rake Angle : If the angle formed by the leading edge and the surface to be cut is obtuse, the rake angle is said to be positive or cutting. Positive rake angles will cut more efficiently than neutral rake angles, which scrap the inside of the canal. K3 positive angle

22. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Tip design Tip design can affect file control, efficiency , and outcome in the shaping of root canal systems . Instrument tips have been described as cutting, noncutting, and partially cutting, The specific design features of the tip, such as tip angle, tip length , cross-section , and tip geometry ,significantly effect t he cutting efficiency of the file and play the important role in Controlling the movement Of the file inside the root canal

23. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Tip design The instrument tip has two functions: to enlarge the canal and to guide the file through the canal. If the canal is smaller than the file, a cutting tip would be more efficient. If the canal is larger than the tip, using a less effective cutting tip can help in preventing transportation. Powell et al pointed out that when this tip “angle” is reduced, the file stays centered within the original canal and cuts all sides more evenly

24. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files Depend on : --- Canal Anatomy configurations, size of the canal , degree of curvature --- File Design --- Experience and skill of the practitioner

25. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files According to File Design : File Tip --- Cutting or non-cutting Cutting Tip A gressive file –efficient and quick cutting process. Caution --- not to be stay in the working length more than one secon d -- must reach the WL only one time . -- Create an elliptical tear upon retraction and this is very difficult to repair and obturate ProTaper – Race systems Non-cutting Tip Safe & create a concentric circle at the end of the root. These are easily filled with a non-standardized cone. Guiding the file inside the root canal. ProFile —K3---GT—M3 M3 noncutting tip

26. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files According to File Design : File Taper --- == File with constant - graduating Taper 0.02—0.04– 0.06 -0.05—0.08 – 0.010– 0.012 -- File has a progressive – variable taper a long its the shank Graduating Taper each successive file is only engaging a minimal aspect of the canal wall Therefore , frictional resistance is reduced and requires less torque to properly run the file. Profile-K3-Race-GT-M3 Progressive Taper One of the benefits of such a design, according to the manufacturer, is reduced torsional loading ProTaper

27. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files According to File Design : Files have a : -- Radial Land , -- Radial with R elief Area -- Non- Radial Land Radial land file ( landed file) - The combination of a non-cutting tip and radial land that keeps a file centered in the cana - radial land supported and strength the blade inside the canal, prevent the transportation - increase frictional resistance

28. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files According to File Design : Files have a : -- Radial Land , -- Radial with R elief Area -- Non- Radial Land Landed File with Relief Area - all the benefits of the landed file - decrease frictional resistance - increase the property of dentine chips canal debrise K3

29. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files According to File Design : Files have a : -- Radial Land , -- Radial with R elief Area -- Non- Radial Land Non-Landed File - decrease frictional resistance - sucking of the file inside the canal when combining with a cutting tip - transportation of the canal ProTape r

30. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files According to File Design : Ranke Angles It is the angle formed by the cutting edge and a radius when the file is sectioned perpendicular to the cutting edge. Positive rake angles will cut more efficiently than neutral rake angles, which scrap the inside of the canal. Most conventional endodontic files utilize a negative or “ substantially neutral ” rake angle. The ProTaper has a negative rake angle but due to its modified blade and progressive taper, the instrument cuts very effectively. many practitioners believe the ideal rake angle is, in fact , slightly positive but not overly positive . An overly positive rake angle will result in digging of the dentin This can lead to separation.

31. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files According to File Design : Ranke Angles The K3 file can have a positive rake angle (red line angle) The K3 is the only third generation file to feature a slightly positive rake angle. This results in optimum cutting efficiency

32. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files According to File Design : Helical Angles Files with a constant helical flute angle allow debris to accumulate, particularly in the coronal part of the file. beside that the file will be more susceptible to the effect of “ screwing in ” forces. -- By varying the flute angles , debris will be removed in a more efficient manner and the file will be less likely to screw into the canal. K3 -- RaCe file, is unique and utilizes an “alternating helical design” that reduces rotational torque by using spiraled and non spiraled portions Along the working length) .This design feature also reduces the tendency of the file to get “ sucked into ” the canal Is the angle that the cutting edge makes with the long axis of the file

33. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files According to File Design : Ranke Angles It is the angle formed by the cutting edge and a radius when the file is sectioned perpendicular to the cutting edge. Positive rake angles will cut more efficiently than neutral rake angles, which scrap the inside of the canal. Most conventional endodontic files utilize a negative or “ substantially neutral ” rake angle. The ProTaper has a negative rake angle but due to its modified blade and progressive taper, the instrument cuts very effectively. many practitioners believe the ideal rake angle is, in fact , slightly positive but not overly positive . An overly positive rake angle will result in digging of the dentin This can lead to separation.

34. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files According to File Design : Pitch --- Pitch is the number of spirals or threads per unit length . --- Variable Pitch or --- Constant Pitch…. Screws The result of a constant pitch and constant helical angles, is a “pulling down” or “sucking down into” the canal. This is particularly significant in rotary instrumentation when using files with a constant taper. Variable Pitch -- Increase the safety movement of the file into the canal by prevent the Pulling or sucking down ProTaper … wave one …K3

35. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files Does the quality of manufacturing make much difference? The quality of manufacturing is the most basic consideration for determining the success or failure of files independent of its composition or design. Less than ideal manufacturing quality controls result in the formation of micro-cracks and defects along the surface of a file.

36. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files

37. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Selection of NiTi Rotary Files Before you choose a rotary file, you must try it Correct Choice in Rotary Files depend on Understand the fundamentals of file design & combine that with your pre-clinical trial . Golden rule

38. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Golden Rules for NiTi Rotary Preparation Assess case difficulty Provide adequate access…. Straight line access 3. Prepare with hand files up to size #20 prior to rotary use--- glide path Use light touch and low rpm --don’t force the file Proceed with crown-down sequence preparation Replace rotary instruments frequent to avoid overuse

39. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary files NiTi Rotary Files Golden Rules for NiTi Rotary Preparation Avoid Cutting With the Entire Length of File—the more file engaged in the root canal , the higher potential for instrument fracture . This total or frictional fit of the file in the canal will cause taper lock and fracture. 8. Don’t Start and Stop —sudden changes in the direction of a rotary caused by the operator must be avoided. A smooth gentle reaming motion is most efficient; rotaries should be inserted and withdrawn from a canal while rotating . 9. Length Contro l is Critical—working length should be well established 10. Don’t rotate a file inside a dry canal

40. Roots Training Center Khartoum Sudan Endodontic Motors GENERATIONS OF MOTORS a) First generation motor without torque control. b) Second generation motor with torque limiter. c) Third generation motor with simple torque control. d) Forth generation motor with apex locator and torque control Endodontic Motors & NiTi Rotary Files A rotary endodontic system incorporates three key elements into its operation : 1) torque-sensing, which monitors how much twisting force the file is encountering 2) auto-reversing, which will reverse the rotation of the file if the file exceeds the torque limit 3) constant file rotational speed, which many file manufacturers recommend .

41. Roots Training Center Khartoum Sudan Endodontic Rotary Motors First-generation motor without torque control second-generation motor with sensitive torque limiter. Third-generation simple torque-controlled motor Forth-generation motor with built-in apex locator and torque control Endodontic Instruments

42. Roots Training Center Khartoum Sudan Endodontic Motors Endodontic Motors & NiTi Rotary Files

43. Roots Training Center Khartoum Sudan Setting Endodontic Motors Speed reverse Torque Gear Program Memorize auto reverse Power Endodontic Motors & NiTi Rotary Files

44. Roots Training Center Khartoum Sudan Endodontic Instruments Setting Endodontic Motors Speed reverse Torque Gear Program Memorize auto reverse Power Endodontic Motors & NiTi Rotary Files

45. Roots Training Center Khartoum Sudan Setting Endodontic Motors Speed reverse Torque Gear Program Memorize auto reverse Power Endodontic Motors & NiTi Rotary Files Importance of Speed Speed refers to revolutions per minute -- r.p.m . In endodontics, speed varies from 150-40,000 rpm Greater the speed , more the cutting efficiency. But at higher speed, there are more disadvantages such as : 1) loss of tactile sensation 2) breakage of instruments preceded by flute distortion 3) change in anatomical curvature of canal 4) loss of control

46. Roots Training Center Khartoum Sudan Setting Endodontic Motors Speed reverse Torque Gear Program Memorize auto reverse Power Endodontic Motors & NiTi Rotary Files Torque Torque is a measure of how much a force acting on an object causes that object to rotate. Factors affecting the torque of a rotary file are the speed , axial pressure, contact area and presence of lubricants.

47. Roots Training Center Khartoum Sudan Setting Endodontic Motors Speed reverse Torque Gear Program Memorize auto reverse Power Endodontic Motors & NiTi Rotary Files Auto reverse During root canal preparation all the instruments are subjected to different levels of torque . If the level of the torque is equal or greater than the torque at deformation or at separation, the instrument will either deform or separate. With low torque control motors , the motor will stop rotating and can even reverse the direction of rotation when the instrument is subjected to torque levels equal to the torque values set on the motor .

48. Roots Training Center Khartoum Sudan Setting Endodontic Motors Speed reverse Torque Gear Program Memorize auto reverse Power Endodontic Motors & NiTi Rotary Files Gear Electric motors with gear are more suitable for rotary NiTi systems because they ensure a constant rpm level however , they also deliver torques much higher than those required to break tip

49. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary Files Rotary hand-pieces - Rotary - Reciprocate - Sonic - Ultrasonic Latch spring latch Friction press hand file Cord motor Cordless motor

50. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary Files Rotary hand-pieces Types of Movement

51. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary Files Rotary hand-pieces Ultrasonic Endodontic Tips These instruments deliver an irrigant which is usually sodium hypochlorite into canal space while cleaning and shaping are carried out by a vibrating K-file

52. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary Files Rotary hand-pieces sonic up and down movement in canal

53. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary Files Apex Locator Root canal length locator An electronic apex locator is an electronic device used in endodontics determine the position of the apical constriction and thus determine the length of the root

54. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary Files Apex Locator Root canal length locator An electronic apex locator is an electronic device used in endodontics determine the position of the apical constriction and thus determine the length of the root

55. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary Files Measurement of canal length

56. Roots Training Center Khartoum Sudan Endodontic Motors & NiTi Rotary Files Thank you لكم اجزل الشكر M3