maxillary permanent canine

PERMANENT MAXILLARY CANINE

Presented by : Dr.Bhavna TyagiMDS 2ND YearUnder the Guidance of :Dr.Deepak Bhargava (HOD), Dr.Puja Bansal (Reader), Dr.Mithilesh N. Mishra (Reader),Dr.Ritika Sharma (Reader),Dr. Vidyadevi Chandavarkar (Reader)

Content • Introduction.

• Chronology.

• Average Dimension.

• Labial Aspect.

• Lingual Aspect.

• Mesial Aspect.

• Distal Aspect.

• Incisal Aspect.

Introduction• Canines are very long and stable teeth.

• Develops from 4 lobes, 3 labial and 1 lingual.

• Middle labial lobe well developed into a cusp.

• There are 4 canines (2 Maxillary & 2 Mandibular) placed at corner of mouth & hence called ‘corner stones’ 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.

• 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.

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

Average Dimension (in mm)

Crown Length 10

Root Length 17

Mesiodistal Diameter at Contact Area 7.5

Mesiodistal Diameter at Cervical Lines 5.5

Labiolingual Diameter at Crest of Curvature 08

Labiolingual Diameter at Cervical Lines 07

Curvature of Cervical Line : Mesial 2.5

Curvature of Cervical Line : Distal 1.5

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.

• 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.

• 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.

• 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.

• 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

LABIAL ASPECT

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.

LINGUAL ASPECT

• 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.

CL : Cervical line C : CingulumMMR : mesial marginal ridgeDMR : distal marginal ridgeLR : lingual ridgeDLF : distolingual fossa

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.

• 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.

• 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 .

• 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.

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.

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

• 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

MLF, mesiolingual fossa;

MCR, mesial cusp ridge;

DCR, distal cusp ridge;

DLF, distolingual fossa;

C, cingulum

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

References

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