Root canal anatomy

Presentation on root canal anatomy of maxillary tooth. . .

1. Root Canal Anatomy Dr. Tasneem Rahman Meem Intern Doctor Mandy Dental College and Hospital 1

2. Introduction The entire internal space or central cavity within a tooth is entirely enclosed by dentin except at the apical foramen It is divided into- Coronal Portion- Pulp Chamber Radicular Portion – Root Canal Pulp Chamber Root Canals 2

3. Pulp Cavity 3

4. Coronal portion i.e pulp chamber reflects the external form of crown Pulp Horns : Pulp horns are landmarks present occlusal to pulp chamber The roof of pulp chamber consists of dentin covering the pulp chamber occlusally or incisally The floor of pulp chamber merges into the root canal at the orifices. Thus, canal orifices are the openings in the floor of pulp chamber leading into the root canals Pulp Chamber 4

5. Canal Orifice: Canal orifices are openings in the floor of pulp chamber leading into root canals Pulp Chamber 5

6. The root canal extends from canal orifice to the apical foramen Root Canal 6

7. It is based on anatomic and histological landmarks in the apical part of the root canal Apical Constriction ( Minor Diameter) Apical Foramen (Major Diameter) Cementodentinal junction Apical Delta Accessory Foramen Lateral Canals Bifurcation/Trifurcation Canals Apical Root Anatomy 7

8. Apical Constriction It is the apical portion of the root canal having the narrowest diameter which is located 0.5-1mm short of the apical foramen 8

9. Apical Foramen It is the main apical opening on the root surface through which blood vessels enter into the root canal The shape of the space between the major and minor diameter has described as- Funnel shaped Hyperbolic Morning glory 9

10. Cementodentinal junction It is the point in the canal where cementum and dentin are united. It is approximately 0.1mm away from the apical foramen 10

11. Apical Delta Opening of accessory and lateral canals in the root surface 11 Accessory Foramen It is a triangular area of the root surrounded by main canal, accessory canal and periradicular tissue

12. Accessory Canal Canal that branches from the main root canal. Most commonly seen in the apical third May also occur in bifurcation and trifurcation area of multirooted tooth which are known as furcation canal 12 Lateral canal Canals that are located approximately at right angle to the main root canal

13. Clinical Significance of Apical Third 13 Most of the curvature occurs in the apical third and so must be prepared very carefully Should be prepared adequately so that the irrigant can chemically debride the accessory canal as instruments cannot reach there

14. Clinical Significance of Apical Third 14 During obturation , the filling should end at the apical constriction otherwise periapical healing will be impaired During periapical surgery apical 3mm of root should be resected to eliminate the accessory canals which lodge microorganism

15. Canal Configuration 15

16. Weine’s Classification 16

17. Weine’s Classification A single canal extends from the pulp chamber to the apex Two separate canals leaving the pulp chamber but exiting as one canal Two separate canals leaving the chamber and exiting as two separate foramina One canal leaving the chamber but dividing into two separate canals and exiting in two separate foramina 17

18. Vertucci’s Classification 18

19. Vertucci’s Classification A single canal extends from the pulp chamber to the apex Two separate canals leave the pulp chamber and join short of the apex to form one canal One canal leave the pulp chamber and divides into two in the root, the two then merge to exit as one canal Two separate, distinct canals extends from the pulp chamber to the apex 19

20. Vertucci’s Classification One canal leaves the pulp chamber divides and then rejoins in the body of the root and finally redivides into two distinct canals short of the apex Three separate, distinct canals extend from the pulp chamber to the apex Two separate canals leave the pulp chamber, merge in the body of the root and redivide short of the apex to exit as two distinct canals One canal leaves the pulp chamber and divides short of the apex two separate, distinct canals with separate apical foramina 20

21. 1. Clinical methods 21 Methods of determining pulp anatomy Anatomy studies Radiographs Exploration

22. 22 Methods of determining pulp anatomy 2. In Vitro methods Sectioning of teeth by CBCT Use of dyes Pulpal tissue remnants fluorescing under blue curing light, marking the presence of the canal orifices Sectioning of tooth by CBCT

23. 23 Variations of pulp space Variations in development Fusion Concrescence Taurodontism Dilacerations Dentogenesis imperfectas 2. Variations in shape of pulp cavity C-shaped canal Curved canal Bayonet-shaped canal

24. 24 Variations of pulp space Variations in pulp cavity due to pathology Variations in apical third Pulp stones Calcifications Internal resorption External resorption Accessory and lateral canals

25. Maxillary Central Incisor Length of tooth (mm) Canal Lateral canals Root Curvature (%) Average length 22.5 One canal 99.4% 24% Straight 75 Maximum length 25.6 Two canal s 0.6% Distal curved 8 Minimum length 21.0 Mesial curved 4 Range 4.6 Labial curved 9 Lingual curved 4 25

26. Maxillary Central Incisor Pulp Chamber Located in the center of the crown with equal distance from the dentinal walls Mesiodistally,The pulp chamber is ovoid in shape Buccopalatally , it is narrow In young patient, Central incisor has three pulp horns Pulp Canal Pulp horn 22.5mm 26

27. Root Canal It has one root with one root canal Root canal is broad labio-palatally , conical in shape and centrally located 17% cases show labial or palatal curvature of the root Lateral canals present in about 24% , usually in the apical third area 27

28. In cross-section , Cervical level: Canal is ovoid mesiodistally Middle root level: Canal is ovoid to round Apical third level: Canal is generally round in shape 28

29. Maxillary Lateral Incisors Length of tooth (mm) Canal Lateral canals Root Curvature (%) Average length 21 One canal 93.4% 10% Straight 30 Maximum length 25.1 Two canal s 6.6% Distal curved 53 Minimum length 20.5 Mesial curved 3 Range 4.6 Labial curved 4 Bayonet and gradual curve 6 29

30. Maxillary Lateral Incisor Pulp Chamber The shape of the pulp chamber is similar to the maxillary central incisor It has two pulp horns , corresponding to the development mammelons 21mm 30

31. Root Canal Root canal has finer diameter than that of central incisor through shape is similar to that The canal is wider labiopalatally Apical region of the canal is usually curved in a palatal direction 31

32. In cross-section , Cervical level: Canal is ovoid labiopalatally Middle third level: Canal is ovoid Apical third level: Canal is generally round in shape 32

33. Maxillary Canines Length of tooth (mm) Canal Lateral canals Root Curvature (%) Average length 26.5 One canal 96.5% 24% Straight 39 Maximum length 28.9 Two canal s 3.5% Distal curved 32 Minimum length 23.1 Mesial curved 0 Range 5.8 Labial curved 13 Lingual curved 7 Bayonet and gradual curve 7 33

34. Maxillary Canines Pulp Chamber Labiopalatally , the pulp chamber is almost triangular shape Mesiodistally , it is narrow Usually one pulp horn is present 26.5mm 34

35. Root Canal There is single root canal which is wider labiopalatally than in mesiodistal aspect Canal is usually straight but may show a distal apical curvature 35

36. In cross-section , Cervical and middle third level: Canal is ovoid in shape Apical third level: At apex it becomes circular 36

37. Maxillary First Premolars Length of tooth (mm) Canal (%) Direction Curvature of roots Single root Double roots Buccal Palatal Average length 21 One canal one foramen 9 Straight 38 28 45 Maximum length 23.8 Two canal s One foramen 13 Distal curved 37 14 14 Minimum length 18.8 Two canals Two foramen 72 Mesial curved Range 5 Three canals Three foramen 6 Labial curved 15 14 28 Lingual curved 3 36 9 Bayonet curve 8 37

38. Maxillary First Premolars Pulp Chamber Pulp chamber is wider buccopalatally two pulp horns ; corresponding to buccal and palatal cusps The roof of the pulp chamber is coronal to the cervical line Floor is convex generally with two canal orifices 21 mm 38

39. Root Canal Two roots When fused roots, a groove running in occlusoapical direction divides the root buccal and palatal portions each containing a single root canal The root canals are usually straight and divergent 39

40. In cross-section , Cervical level: Canal is ovoid in shape Middle and apical third level: Canals show circular shape 40

41. Maxillary Second Premolars Length of tooth (mm) Canal (%) Root Curvature (%) Average length 21.5 One canal One foramen 75 Straight 9.5 Maximum length 23 Two canal s Two foramen 24 Distal curved 27 Minimum length 19 Three canals 1 Mesial curved 1.6 Range 4 Buccal curved 12.7 Lingual curved 4.0 Bayonet curve 20.6 41

42. Maxillary Second Premolars Pulp Chamber Pulp chamber is wider buccopalatally Narrower mesiodistally Pulp horn under each cusp, buccal pulp horn more prominent 21.5 mm 42

43. Root Canal In more than 60% cases, single root with single canal is found If there are two canals, they may be separated or distinct along the entire length of the root Canal is wider buccopalatally forming ribbon like shape 43

44. In cross-section , Cervical level: Canal is ovoid and narrow in shape Middle third level: Canal is ovoid Apical third level: At apex it becomes circular 44

45. Maxillary First M olars Length of tooth (mm)` Mesiobuccal (mm) Distobuccal (mm) Palatal (mm) Canal (%) Direction Curvature of roots Mesial (%) Distal (%) Palatal (%) Canals in mesiobuccal root Average length 19.9 19.4 20.6 Three 41.1 Straight 21 54 40 One canal one foramen 41.1 Maximum length 21.6 21.2 22.5 Four 56.5 Distal curved 78 17 17 Two canal s One foramen 40 Minimum length 18.2 17.6 17.6 Five 2.4 Mesial curved 19 19 Two canals Two foramen 18.9 Range 3.4 3.6 3.8 Buccal curved Lingual curved Bayonet curve 1 10 10 45

46. Maxillary First M olars Pulp Chamber Largest pulp chamber Four pulp horns ; mesiobuccal , mesiopalatal , distobuccal and distopalatal Roof ; Rhomboidal in shape Roof converges, palatal wall disappears and forms a triangular form 21 mm 46

47. Maxillary First M olars Pulp Chamber Anatomic dark lines in the floor connect the orifices Orifices are located in the 3 angles of the floor Mesiobuccal orifice under mesiobuccal cusp May have depression in the palatal end of the mesiobuccal orifice where a 4 th canal may be present MB2 canal is located mesial to or directly on a line between the MB1 and palatal orifice 47

48. Root Canal Generally three roots with three or four canals Two canals in mesiobuccal root are closely interconnected and sometimes merge into one canal 48

49. Root Canal Mesiobuccal canal: Narrowest of the three canals Flattened in mesiodistal direction at cervix but becomes round as it reaches apically Distobuccal canal: Narrow, tapering canal Flattened in mesiodistal direction but generally it is round in cross- section 49

50. Root Canal Palatal canal: Largest diameter In cross-section, rounded triangular coronally and round apically Palatal canal can curve buccally in the apical one-third Lateral canals are found in 40 percent of the molars at apical third and at trifurcation area 50

51. Maxillary Second M olars Length of tooth (mm)` Mesiobuccal (mm) Distobuccal (mm) Palatal (mm) Canal (%) Direction Curvature of roots Mesial (%) Distal (%) Palatal (%) Canals in mesiobuccal root Average length 20.2 19.4 20.8 Three 54 Straight 22 54 63 One canal one foramen 63 Maximum length 22.2 21.3 22.6 Fused 46 Distal curved 54 Two canal s One foramen 13 Minimum length 18.2 17.5 19.0 Mesial curved 17 Two canals Two foramen 24 Range 4.0 3.8 3.6 Buccal curved 37 Lingual curved 51

52. Maxillary Second molars Pulp Chamber Similar to maxillary 1st molar, except narrower mesiodistally Roof- Rhomboidal in shape Floor- Obtuse triangle Mesiobuccal and distobuccal canals closer together 21 mm 52

53. 53 Root Canal Mesiobuccal root: Broad buccolingually Prominent depression in mesial and distal surfaces 1 or 2 canals Distobuccal root: Rounded/Ovoid, single canal Orifice appears on same line joining mesiobuccal and palatal canals Palatal root: Broad mesiodistally Ovoid ,single canal

54. 54 Conclusion Through knowledge of root canal anatomy and access cavity preparation will enable the clinician to produce endodontic treatments of high quality and considerable longevity A successful treatment outcome depends on the complete debridement and disinfections of all canals

55. Thank Y ou For your attention. . .