Peramanent Maxillary Canine

Permanent Maxillary Canine (corner teeth of the oral cavity )

1. Maxillary Canine DR MONIKA NEGI MDS ORAL PATHOLOGY ,MICROBIOLOGY AND FORENSIC ODONTOLOGY

2. contents • Introduction. • Chronology. • Average Dimension. • Labial Aspect. • Lingual Aspect. • Mesial Aspect. • Distal Aspect. • Incisal Aspect

3. introduction • Canines are very long and stable teeth. • Develops from 4 lobes, 3 labial and 1 lingual . • Middle labial lobe developes into a cusp.

4.  There are 4 canines (2 Maxillary & 2 Mandibular ) placed at corner of mouth & hence called ‘ corner tooth ’ of the dentition. • Single pointed cusp present so also called cuspids . • The canine's role in mastication is mainly tearing , which is intermediate between incising of anterior teeth & grinding of the posterior teeth

5. • Canine eminence- bony ridge over the labial surface of roots, has a cosmetic value helps form a foundation that ensures normal facial expression at the corners of the mouth. • Arch position - The permanent maxillary canine replaces deciduous maxillary canine & is located 3rd from midline in each maxillary quadrant. • Mesial contact : Maxillary lateral incisor • Distal contact : Maxillary first premolar .

6. Chronology • First evidence of calcification : 4-5 mo • Enamel completed : 6-7 yr • Eruption : 11-12yr • Root completed : 13-15y

7. Labial aspect The crown of maxillary canine is narrower mesiodistally than that of maxillary central incisor. • It has two slopes (cusp ridges), the mesial slope being shorter than the distal slope . • The labial surface is smooth and bulky in the middle because of the labial ridge.

8. • Imbrication lines can often be found in cervical 3rd of the facial surface : “Lines of Pickerell ”. • Mesial outline : usually convex from the cervix to the center of the mesial contact area or the crown may exhibit a slight concavity above the contact area . • Rounded mesioincisal angle .

9. • Height of contour ( mesial margin) : at contact area ( junction of incisal & middle thirds). • Distal Outline : usually concave between CEJ and DCA . • Distal margin : Shorter than the mesial margin & also has a more rounded incisal angle

10. • Height of contour : at contact area (middle 3rd) • Cusp tip is in line with the center of the root . • Cusp slopes shows tendency toward concavity(notch) before wear has taken. • Labial surface is convex in all directions , but curvature is more pronounced mesiodistally . • General outline of the surface is pentagonal .

11. • Incisal aspect has a large cusp with a pointed cusp tip . • Incisal margin - divided into two components by tip of cusp & are termed the mesioincisal and distoincisal slopes (or mesial & distal cusp ridges). • Root appears slender, conical in form with a blunt apex, root may curve mesially or distally. Labial aspect Labial ridge Cusp tip Distal cusp ridge Mesial Cusp Ridge

12. Lingual Aspect • Crown and root are narrower lingually . • Cingulum is well developed, large & sometimes pointed like a cusp. • Cervical line curves asymmetrically toward the apex with a slight offset to the distal.

13. • Strongly developed marginal ridges , occasionally a well- developed lingual rigde at the center with two shallow concavities namely; Mesial and Distal lingual fossa . • Root narrower than labial , mesial and distal surface of root is visible lingually . • Developmental depressions M and D may be seen .

14. Mesial Aspect • From the mesial aspect canine looks similar but bulkier than maxillary central incisor. • Maxillary canine is the widest anterior tooth labio lingually . • The outline of the crown is wedge shaped , the greatest measurement being at the cervical 3rd . • Wedge point being represent by the tip of the cusp.

15.  Below the cervical 3rd of the crown , the labial face may be presented by a line only slightly convex from the crest of curvature at the cervical third to the tip of the cusp. • Labial outline exhibits more convexity. • The lingual outline of the crown may represented by a convex line describing the cingulum , which convexity straightens out as the middle 3rd is reached , becoming convex again in the incisal 3rd.

16. CEJ curves approximately 2.5 mm incisally . • The contact area is near the junction of the incisal and middle third. • Root outline is conical, tapered or blunt pointed apex, may curve labially

17.   Labial outline of root maybe almost perpendicular . • Mesial surface of root appears broad with shallow developmental depression that help to anchor the teeth in the alveoli and help prevent rotation and displacement. • A line bisecting the cusp is labial to a line bisecting the root .

18. Distal Aspect • Same as mesial except the following: a . Less curvature of CEJ ( approx. 1 mm ) . b. Contact area is broader . c. Distal marginal ridge is heavier . d. More irregular in outline. e. More concave surface. f. More pronounced root developmental depression.

19. Incisal Aspect • The labiolingual dimension is greater than the mesiodistal dimension • Maxillary canine is generally convex in both its labial and lingual outlines • The cusp tip is labial to the centre of the crown labiolingually and mesial to the centre mesiodistally • The labial ridge and the cingulum are very noticeable from this aspect Incisal aspect

20.  When cut cross- sectionally , mesial section, shows greater labiolingual bulk , crown gives impression of having all the distal portion stretched to contact first premolar. • Line bisecting cusp and cusps ridges in the MD direction is almost always straight . • Distal slope is longer than mesial slope

21. MLF, mesiolingual fossa ; MCR, mesial cusp ridge; DCR, distal cusp ridge; DLF, distolingual fossa ; C, cingulum

22. Root • Only one • Longest and strongest of all the teeth in the mouth • Mesial & distal surfaces of root have developmental depressions • From all aspects, the root tapers gradually to a sharp, or slightly blunted apex • Wider labiolingually than mesiodistally • Lingual and labial surfaces are convex

23. References • WHEELER’S dental anatomy, physiology , and occlusion 8th edition .