1. MANAGEMENT OF CURVED ROOT CANAL SYSTEMS MISSION IMPOSSIBLE?
DR TOM JM DIENYA
BDS(NBI), CIBRD(KASADA), MDSc-Endo(Mal), Cert. In Oral Implantology (Mal)
SPECIALIST ENDODONTIST,IMPLANT PRACTITIONER AND LECTURER
Dept of Conservative Dentistry
University of Nairobi
Practice limited to Endodontics and implantology or

4. Introduction and Lit review
The goal of endodontic therapy is the prevention and/or elimination of pathosis of endodontic origin
Correct diagnosis
SUCCESFULL
RCT
Cleaning and Debridement
Complete obturation
(European Society of Endodontology Consensus, 1994, Omer et al., 2004, , FDI World Dental Press, 2005 ).

5. Introduction and Lit Review cont..
Inadequate understanding
Of Root Canal
Systems
Detailed Knowledge of ROOT
CANAL SYSTEM
Improper shaping
And
Inadequate Cleaning
SUCCESSFUL ROOT
CANAL
Poor Obturation
Treatment
Failure
Omer et al.,2004,Mikrogeorgis et al.,1999,Al-Nazhan,2007
Carrotte,2004

6. INTRODUCTION CONT..
A tooth with a straight root and a straight root canal is an exception rather than being normal because most teeth show some curvature of the canal (weinne,scheinder,kyomin).
Tomes, in 1848, called such curvatures as dilacerations

7. Dilaceration: Defination
It refers to an angulation or a bend or a curve in the root or crown of formed tooth or a deviation or in the linear relationship of a crown of a tooth to its root.

8. Epidemiology
In most studies,prevalence of curvature ranged between 80 to 100%. Dienya et al 2009 in a study of 400 maxillary and mandibular 1st molars in a Kenyan population got 91% curvature. Dr Schaffer in Germany examined 1163 root canals and found that 980 (84%) were curved and 65% showed an angle > 27 degrees with radii < 40 mm.

9. CAUSE
The condition is thought to be due to trauma during the period in which tooth is forming.
The result is that the position of the calcified portion of the tooth is changed and the remainder of the tooth is formed at an angle

10. Types of curvatures Curved canals can be:
Gradual curvature of the canals in the coronal,middle or apical third;
Acute curvature in the apical third;
Curvature throughout the canal;
S-shaped root canal.

11. Mandibular 1st molar with GRADUAL distal curvature of the mesial root

12. Maxillary molar with the DB root showing ACUTE curvature in the apical third

13. Buccal curvature at the tip of a palatal root

14. Mandibular 1st molar with an S-curvature of the D root

15. Combination of S-shaped canals and gradual shape

16. THE STAIR CASE CURVE

17. THE DECEIVING CURVE ---distal root curves lingually

18. THE CONSEQUENCES EXCESSIVE FLARING LEDGING APICAL TRANSPORTATION
APICAL PERFORATION

19. SHORT OBTURATION- due to inability to negotiate curvature

20. Instruments break unexpectedly Separated apical part
Common to all curvatures:
Instruments break
unexpectedly
Separated apical part
is difficult to remove
A Major Drawback !

21. Instruments separation just at the beginning of the curve

23. Missed canal in maxillary 1st molars
Note : Canal was missed probably due to it being hidden at the beginning of the curve
presence of lamina dura—indicates canal presence

24. pain

25. Management Start with accurate diagnosis
preoperative radiographs taken with parallelling technique with at least two different views-SLOB RULE:
UPPER TEETH-normal buccal view,then use rule MMMM
LOWER TEETH—normal buccal view then use the rule DMMD or use CBCT OR DIGITAL X-RAYS

26. Paralleling technique in the lower jaw

27. Parallel periapicals

29. Root canal configurations obtained with CBCT
Type IV
Type III
Type II
Type I
Additional canal 2
Additional Canal 3
Additional
Canals 1
Type VI
Type V

30. Make a good access cavity

32. Pitfalls of inadequate access
Remnants of pulp roof removed by slow speed round bur
Straight line access achieved
Inadequate acess easily leads to ledging

33. Determine the DEGREE OF curvature
Before initiation of treatment, an estimate should be made as to the degree of curvature of canals by seeing the radiograph, probing OR schneiders method
The interior angle is formed by intersection of the straight line from the orifice through coronal portion of the root and another straight line from apex through apical portion of canal

34. Take an impression of the canal
S-shaped
c-shaped
J--shaped
Merging canals

35. USE CROWN DOWN TECHNIQUE

36. Divide the root into three

37. Flare coronal one third and open up orifice-use orifice shapers
Or 25/07 in mtwo system or sx in protaper system—Do not use gates glidden.

38. ENDOFLARE 2 ENDOFLARE® filing (penetration < coronal third) 1
Before ENDOFLARE® filing - Pronounced dentinal overhang 3
After ENDOFLARE® filing - Elimination of the coronal strains

39. BEFORE
AFTER
Pr. CALAS

40. Working length

41. Working length-practical determination
Use apex locators—such as raypex 6 or vdw

43. motor

44. No direct measurements on file
Direct measurements are likely to introduce errors

46. MEASURE CURVATURE by tracing

47. rules R>160------stainless steel handfiles can be used
R—140—160---consider precurving stainless steel files or use rotary
R –100—140—rotary with initial glide path;use highly flexible files with radial lands or use rotary in straight portion and hand files apically
R –90—100—niti hand files with high flexibility; orifice shapers only coronally
R—90 or less—consider apicoectomy and reverse filling,aggressive use of hand niti

49. management USE OF HAND NITI FILES
Tedious..some files can break due to torsional stress

50. PRECURVING STAINLESS STEEL FILES

51. Crown Down Technique

52. Crown Down Technique Coronal third Orifice shapers
Middle third 0.06 taper rotary
Apical third 0.04 OR 0.02 taper hand or rotary

53. FILES TO USE

54. HERO Shapers
Red sequence

55. Red sequence for average difficult cases
25 6%
25 4%
30 4% + +
2/3 WL WL WL
2/3 WL WL

56. HERO Shaper
Yellow sequence

57. HERO Shaper
Yellow sequence

58. Yellow sequence for difficult cases
20 6%
20 4%
25 4%
30 4% + + +
2/3 WL WL WL WL
2/3 WL WL

59. Preparation of coronal third

60. Preparation of middle third

61. Preparation of the apical third
Prepare to actual working length
Use 0.04 taper NiTi hand files in sequence smaller to larger

62. Preparation of apical third

63. Irrigation needle should have side opening to opening to preven driping of irrigant fluid hence pain

64. Acoustic streaming around a file in free water (left) and a schematic drawing (right).

65. cases

67. Extensive Amalgams-can be very painful necessitating endo-therapy

70. Single cone technique????

71. THANK YOU SO MUCH FOR YOUR ATTENTION