Oral Anatomy: Tooth identification

Chapter 10

1. Chapter 10 Tooth Identification Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

2. Curvature of the CEJ is about 1 mm less on the distal surface of the tooth than on the mesial. If the tooth roots curve, they usually curve distally, especially at the apex of the root. The distal incisal edges of anterior teeth are more rounded than the mesial incisal edges. General Rules of Tooth Identification 2 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

3. Mandibular anterior teeth tend to wear on the labial incisal edges; maxillary teeth wear on the lingual incisal edges. Permanent molars are generally smaller in height and have fewer cusps the more posterior they are positioned. Permanent molars tend to have more secondary and tertiary anatomy the more posterior they are positioned. General Rules of Tooth Identification 3 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

4. Roots of molars tend to be shorter and closer together the more posterior the molars are positioned, and the roots are often fused into one. First molars have the widest and longest roots of all molars. The more posterior the molars are positioned, the more variation of anatomy is evident. General Rules of Tooth Identification 4 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

5. Incisors 5 Incisors Incisal two thirds appear flattened on labial and lingual sides. Incisal edge, not a cusp. Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

6. Incisors 6 Maxillary Crown wider mesiodistally than faciolingually. Root has triangular cross section; broader on facial side. Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

7. Incisors 7 Maxillary Central Greater crown-to-root ratio than lateral incisors. Mesioincisal angle sharp (90 degrees). Contact area in incisal third. Broad, smooth lingual fossa with cingulum. Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

8. Incisors Maxillary Lateral Lesser crown-to-root ratio than central incisors. Mesioincisal angle rounded. Contact area at junction of middle and incisal thirds. 8 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

9. Incisors Maxillary Lateral (Cont.) Small cingulum; often with a lingual pit. 9 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

10. Incisors Maxillary Lateral: Right-Left Mesioincisal angles more square than distoincisal angles. Crest of cervical line more often displaced toward distal from labial or lingual view. 10 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

11. Incisors Maxillary Lateral: Right-Left (Cont.) Mesiocervical line curves more incisally than distocervical line. 11 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

12. Incisors Mandibular Smaller than maxillary central or lateral incisor. Crown wider faciolingually than mesiodistally. Root with oval cross section. 12 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

13. Incisors Mandibular (Cont.) Incisal edge wears on labial surface. Incisal edge angled toward the lingual side. 13 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

14. Incisors Mandibular Central Incisal view: incisal edge perpendicular to faciolingual axis of tooth. Mesial and distal lobes appear identical. 14 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

15. Mandibular Central: Right-Left Cervical line curves more incisally on mesial than on distal surface. Height of curvature of cervical line on mesial greater than on distal surface. Root tip may have slight distal curve. Incisal edge worn wider on distal surface. Incisors 15 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

16. Incisors Mandibular Lateral Incisal view: distoincisal edge angled toward lingual side. Distal lobe appears larger than mesial lobe. 16 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

17. Mandibular Lateral: Right-Left Cervical line curves more incisally on mesial than on distal surface. Incisal view: distal half of incisal edge rotated toward lingual side. Incisal edge worn wider and longer on distal surface. Incisors 17 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

18. Canines Single conical cusp with well-developed mesiofacial lobe. Lingual cusp ridge from cusp tip to lingual fossa. Canines 18 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

19. Canines Maxillary Canines Lingual surface has well-developed marginal ridges, cingulum, and fossa. 19 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

20. Canines Maxillary Canines (Cont.) Larger crown than incisors and lower canines; more distal convexity. Cusp tip directly midcenter over root. 20 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

21. Canines Maxillary Canines: Right-Left Cervical line curves more incisally on mesial than on distal. Incisal view: distofacial lobe elongated. 21 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

22. Canines Maxillary Canines: Right-Left (Cont.) Facial view: distal surface rounded. Contact area located more cervically. 22 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

23. Canines Mandibular Canines Lingual surface almost smooth with poorly developed ridges, cingulum, and fossa. Narrower mesiodistal width than maxillary. 23 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

24. Canines Mandibular Canines (Cont.) More wear on facial (labial) surface when compared with maxillary canine. 24 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

25. Premolars At least two cusps, one a single facial cusp, with one or two lingual cusps. Premolars 25 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

26. Premolars Maxillary Premolars Two major cusps; buccal and lingual. Wider faciolingually than mesiodistally. Proximal view: facial and lingual cusps nearly same height; located over root trunk. 26 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

27. Premolars Maxillary First Premolar Facial cusp slightly longer than lingual cusp. 27 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

28. Maxillary First Premolar (Cont.) Often has two roots; buccal and lingual. Occlusal surface has well-developed central groove, with little supplemental grooving. Mesial surface has depression above contact area below cervical line and extending onto root. Maxillary First Premolar: Right-Left Mesial marginal groove. Cervical line on mesial curves more occlusally than on distal surface. Premolars 28 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

29. Premolars Maxillary First Premolar: Occlusal View Mesiofacial cusp ridge forms 90-degree angle with mesial marginal ridge. Distofacial cusp ridge forms rounded angle with distal marginal ridge. 29 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

30. Premolars Maxillary Second Premolar Facial and lingual cusps are nearly same height. Usually single rooted. 30 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

31. Premolars Maxillary Second Premolar (Cont.) Short central groove; numerous supplemental grooves. No depression on mesial or distal crown surfaces. Right-left: lingual cusp displaced toward mesial. 31 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

32. Mandibular Premolar Prominent facial cusp with one or two much smaller lingual cusps. Nearly equal faciolingual and mesiodistal widths. Premolars 32 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

33. Premolars Mandibular Premolar (Cont.) Proximal view: facial cusp much larger with tip at or near midaxis of root; lingual cusp(s) extend lingually past lingual border of root. 33 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

34. Premolars Mandibular First Premolar Proximal view: occlusal surface tilted toward lingual side. Cervical line on mesial curves more occlusally than on distal. 34 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

35. Premolars Mandibular First Premolar (Cont.) Occlusal view: oval outline with strong transverse ridge and no central pit. 35 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

36. Premolars Mandibular First Premolar: Right-Left Depression or groove where mesial marginal ridge joins lingual cusp ridge. Distal marginal ridge more prominent. 36 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

37. Premolars Mandibular Second Premolar Occlusal view: pentagonal outline, with a central pit and no transverse ridge. 37 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

38. Premolars Mandibular Second Premolar (Cont.) Proximal view: occlusal surface less lingually tilted. May have two lingual cusps. 38 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

39. Mandibular Second Premolar: Right-Left Proximal view: more of occlusal surface visible from distal than from mesial because of distal inclination of crown-to-root axis. Premolars 39 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

40. Molars Three to five cusps, with at least two facial. Maxillary Molars Crowns wider faciolingually than mesiodistally. Three roots: two on facial and one on lingual side. Molars 40 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

41. Molars Maxillary First Molar Occlusal view: strong oblique ridge less likely to be crossed by a groove. 41 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

42. Molars Maxillary First Molar (Cont.) Three roots widely separated. Often fifth cusp (Carabelli’s) on mesiolingual cusp. 42 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

43. Molars Maxillary Second Molar Occlusal view: smaller oblique ridge usually interrupted by a groove. Right-left: mesiolingual cusp larger than distolingual cusp. 43 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

44. Molars Maxillary Second Molar (Cont.) Roots closer together. No fifth cusp. Distolingual cusp smaller than on first molar. 44 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

45. Molars Maxillary Third Molar Distolingual cusp progressively smaller or missing entirely. Roots either fused or very close together and much shorter. 45 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

46. Molars Maxillary Third Molar (Cont.) No oblique ridge. Right-left: distofacial cusp much shorter than other molars. Roots curved distally. 46 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

47. Mandibular Molars Crowns wider mesiodistally than faciolingually. Two roots: one mesial and one distal. Molars 47 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

48. Molars Mandibular First Molar Three facial cusps and two facial grooves. Roots widely separated and relatively vertical. 48 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

49. Molars Mandibular First Molar: Right-Left Distal cusp is smallest facial cusp. 49 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

50. Molars Mandibular Second Molar Only two facial cusps and one facial groove. Roots close together. 50 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

51. Molars Mandibular Second Molar (Cont.) Occlusal groove well defined but travels straight mesial to distal and forms a cross with facial and lingual grooves. 51 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

52. Molars Mandibular Second Molar: Right-Left Buccal height of contour in cervical third; lingual height of contour in middle third. 52 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.

53. Molars Mandibular Third Molar Secondary and tertiary anatomy. Short roots, often fused and curved distally. Right-left: crown tapers distally; wider faciolingually on mesial than on distal surface. 53 Copyright © 2014 by Mosby, an imprint of Elsevier Inc. Copyright © 2003 by Mosby, Inc., an affiliate of Elsevier Inc. Previous editions copyrighted 1977, 1982, 1986, 1990, 1994, 1998.