MAXILLARY AND MANDIBULAR CANINES

LOCATION AND NUMBER The permanent canines are four in number and are located distal to the lateral incisors and mesial to the permanent 1st premolars Are at the “corners” of the mouth

NAMES AND IDENTIFICATION Maxillary right canine #6 Maxillary left canine #11 Mandibular right canine #27 Mandibular left canine #22

SHAPE The longest (crown and root) and most stable of teeth. The “corner stone of the arch”. Overdeveloped middle labial lobe results in a single pointed cusp

FUNCTIONS Prehension of food Protect the posterior teeth during jaw movements (working or laterotrusive movements) Cosmetic value: Helps support facial musculature Transitional tooth from anterior to posterior

THE MAXILLARY CANINE General characteristics Development Views Axial inclination and occlusion Root and pulp spaces

GENERAL CHARACTERISTICS Wider labiolingually to offset forces of function Greatest cingulum development Longest root; sometimes mandibular canine is as long Usually larger than the mandibular canine(Arch trait)

DEVELOPMENT First calcification 4-5 years Enamel completed 6-7 yrs Eruption 11-12 yrs Root Completed 12-15 yrs Develops from 4 lobes: 3 labial, 1 lingual

LABIAL VIEW About 1 mm narrower mesiodistally than Max central Mesial outline is convex Emergence angle is slightly angled but flat Mesial cusp ridge may show a slight concavity

LABIAL VIEW (CON’T) General shape is a pentagon Cusp tip is usually centered Mesial and distal cusp ridges are flat or slightly concave; can be related to lobe development

LABIAL VIEW (CON’T) Mesial and distal surfaces have a flat or concave surface in the gingival 1/3rd , then become convex, forming an s-shape Mesial contact is at junction of middle and incisal 1/3rd of crown. This “high shoulder”(mesioincisal angle) results from a shorter, less sloping mesial ridge

LABIAL VIEW (CON’T) Distal line angle is very convex resulting in marked tapering at CEJ (Arch trait) Incisal margin may form from 1/2 to 1/3rd of the anatomic crown Crest of curvature of CEJ is slightly mesial to long axis

LINGUAL VIEW Considerably narrower than labial CEJ: A slighter curvature (compared to incisors) Cingulum: large and sometimes pointed Mesial and distal marginal ridges are prominent

LINGUAL VIEW (CON’T) Lingual ridge: may or may not be continuous from the incisal portion of the cingulum to the cusp tip Presence of mesiolingual and distolingual fossae Lingual pit may be present What other maxillary tooth may have a lingual pit?

MESIAL VIEW Triangular outline of anterior teeth caused by extreme relative thickness of the central 1/3rd of crown and root Crest of curvature is more incisal due to development of lingual and middle lobes Greater convexity of labial surface than the incisors

MESIAL VIEW Lingual surface shows less convexity than the max central and lateral incisors A line bisecting the cusp labiolingually is labial to a line bisecting the root labiolingually

MESIAL VIEW (CON’T) Incisal edge is thick (Arch trait) Labial margin is relatively straight from the middle of the root to the junction of the cervical middle 1/3 of the crown, where the height is located (Arch trait) Lingual height of contour is close to the cervical line

DISTAL VIEW CEJ is less curved Longitudinal groove is usually longer and deeper

Maxillary Canines

INCISAL VIEW Characterized by asymmetry Labiolingual width usually greater than mesiodistal

INCISAL VIEW (CON’T) Distal bulk is greater than Mesial Large labial ridge; highly developed middle labial lobe Cingulum is highly developed

Incisal View

Arch TRAITS Possesses a single conical cusp Largest single root; thickest labiolingually-well anchored Only cusped tooth that functions on lingual surface(?)

SUMMARY (ARCH TRAITS) Crown is larger than opposing mand canine Mesial and distal margins from labial tend to converge markedly toward the cervix Incisal margin of the crown occupies at least 1/3rd of the crown height

SUMMARY (ARCH TRAITS-CON’T) Mesial and distal cusp ridges, marginal ridges, lingual ridge and the cingulum are more accentuated than in the mandibular canine Lingual pit and/or grooves are common features Labiolingual diameter of crown near the cervix is greater than the mandibular canine

OCCLUSION The max canines occludes with the mand canines and 1st premolars

AXIAL INCLINATION Mesiodistal inclination 17 degrees to distal (root) Faciolingual inclination 16 degrees to lingual (root)

ROOT Max canine has longest root Labiolingually: narrow, triangular, pointed apex Apical 1/3rd of the root often has a sharp curvature to either the mesial or distal (usually the distal) Mesiodistally: broad, triangular, blunt apex

PULP SPACES Pulp chamber and canal is widest faciolingually and changes from an elliptical to a circular form apically About 25% have accessory canals

THE MANDIBULAR CANINE General characteristics Development Views Axial inclination and occlusion Root and pulp spaces

GENERAL CHARACTERISTICS Similar to max canine Narrower mesiodistally than max canine Cusp, marginal ridges, and cingulum development is not as extensive as max canine Bifurcated roots occur occasionally

DEVELOPMENT 4 lobes (same as for all anterior teeth) 1st calcification 4-5 yrs Enamel completed 6-7 yrs Eruption 10-11 yrs Root completed 12-14 yrs What is completed before a tooth erupts?

LABIAL VIEW About 1 mm narrower mesiodistally than max canine Crown appears longer than max canine due to narrowness of crown and height of interproximal contacts

LABIAL VIEW (CON’T) Mesial cusp ridge is shorter than the distal Cusp tip in line with center of root Mesial outline is straight and continuous with root Labial line angles curve only slightly toward cervix

LABIAL VIEW (CON’T) Crown often tilted distally in relation to the long axis of the tooth (Arch trait) Mesial contact is at incisal 1/3rd Distal contact is more incisal than max canine (junction of incisal and middle1/3rd )

LABIAL VIEW (CON’T) Facial ridge is less prominent and cervical line is more symmetrical Incisal margin confined to incisal 1/4th or 1/5th, giving a long, narrow appearance (Arch trait)

LINGUAL VIEW Flatter, smoother, less developed than max canines (Arch trait) Lingual surface is approximately ½ the width of the labial surface

PROXIMAL VIEW Labial surface is less curved than max canine Labial height of contour is less than 0.5 mm Incisal ridge is not as wide as the max canine Lingual outline is flatter

PROXIMAL VIEW (CON’T) Cusp tip is positioned lingually Greater curvature of CEJ; more incisally located than max canine CEJ: greater curvature on the mesial surface than the distal surface Root is narrower than maxillary canine

INCISAL VIEW Lingual inclination of cusp tip and mesial and distal incisal ridges Mesial and distal halves more symmetrical (Arch trait) Smaller lingual ridge and incisal ridges Labial surface is smoother Lingual appears more round

OCCLUSION The mandibular canine occludes with the max canine and lateral incisor

AXIAL INCLINATION Mesiodistal inclination 6 degrees to distal (root) Faciolingual inclination 12 degrees to lingual (root)

ROOT Longest root of any tooth in mandibular arch Root tapers toward the apex and is more pointed than the maxillary canine root Apical 1/3rd may show a slight Dilaceration in the mesial direction Longitudinal grooves are present; root may be bifurcated

PULP SPACES Pulp canal of the mand canine often has two root canals Generally very similar to max canine

SUMMARY (ARCH TRAITS) Crown is smaller than max canine Mesial and distal margins as seen from labial tend to be parallel or slightly convergent toward cervix

SUMMARY (ARCH TRAIATS-CON’T) Incisal margin of the crown is confined to the incisal 1/4th or 1/5th of the crown, giving the tooth a long, narrow appearance Entire lingual surface is flatter, with much less prominence of margins, ridges and cingulum

SUMMARY (ARCH TRAITS-CON’T) No lingual pits or grooves Labiolingual diameter of the crown near the cervix is less than max canines Mesial and distal halves of the crown, when viewed from the incisal aspect, are more symmetrical Variations exist; more so than max canines