[6] Maxillary and Mandibular Cuspids Part 1

Cuspids

• Works alongside incisors and premolars to cut, pierce, or shear food

• Support the lip and facial muscles through the canine eminence*

  • Labial portion of the root and the bony ridge over it

• Serves as the foundation for normal facial expression at the corners of the mouth

• Important guideposts in occlusion

Canine Protected Occlusion

the deep overlap of the canines serve as a protective mechanism by relieving the posterior teeth from excessive lateral excursive forces (when the mandible moves from side to side)

Cornerstones

Canines are also called the “_______” of the arches

Stable

Canines are the most ____ tooth in the mouth because of its anchorage in the alveolar jaws

Which of the following is NOT a function of canines?

Cut, pierce, or grind food

Which canine is the SCOLIOSED canine?

Mandibular Canine

What is a unique feature of the canine?

Labial Ridge

Which of the following is TRUE about canines?

The distal cusp slope is longer than the mesial cusp slope.

Which canine has the cingulum centered mesiodistally?

Maxillary Canine

Determine if the following is found on Maxillary Canine,

Mandibular Canine, or Both.

This tooth exhibits less cervical line curvature

on the distal aspect than on the mesial aspect.

Both

Determine if the following is found on Maxillary Canine,

Mandibular Canine, or Both.

There is an almost continuous crown-root

outline on the mesial surface of the tooth.

Mandibular Canine

Determine if the following is found on Maxillary Canine,

Mandibular Canine, or Both.

On which tooth cusp angle is most acute?

Mandibular Canine

Determine which characteristics are common to all

anterior teeth. Answer either Yes or No.

Most are mono-rooted.

Yes

Determine which characteristics are common to all

anterior teeth. Answer either Yes or No.

The mesioincisal angle is sharp while the

distoincisal angle is rounded.

No

Determine which characteristics are common to all

anterior teeth. Answer either Yes or No.

The mesial outline is flatter/straighter than the

distal outline.

Yes

Determine which characteristics are common to all

anterior teeth. Answer either Yes or No.

Cingulum is centered mesiodistally.

No

Determine which characteristics are common to all

anterior teeth. Answer either Yes or No.

The root at the apex bends to the distal.

No

Determine which characteristics are common to all

anterior teeth. Answer either Yes or No.

The CEJ is more convex on the mesial.

Yes

Determine which characteristics are common to all

anterior teeth. Answer either Yes or No.

The presence of developmental depressions on

the root surface.

No

Canines have ____-shaped crowns.

Pentagon

Incisal ridge has ____ inclines by a single cusp where mesial slope is shorter that the distal

2

Maxillary Cuspids

Labial

• Prominent vertical labial ridge

• Proportion is greater labiolingually than mesiodistally

Lingual

• Crown and root are narrower lingually than labially

• Has a large cingulum, sometimes pointed like a small cusp at the incisal border

• Has a prominent lingual ridge

• Mesial and Distallingual fossae are bound by the lingual ridge and marginal lines

Proximals

• Cusp tip is more labial than root apex

• Roots have shallow developmental depressions that are more pronounced on the distal

Incisal

• Asymmetrical crown outline: greater width labiolingually than mesiodistally

• Cusp tip is slightly labial and more mesial 

• Cingulum is large and centered mesiodistally

• Mesial half is bulkier than the distal half

• Distal portion is stretched to allow contact with 1st premolar

Mandibular Cuspids

Labial

• Less pronounced labial ridge

• Long and narrow

• Outline:

• Mesial: slightly convex to almost straight in line with the mesial root surface

• Distal: convex at the incisal two-thirds,, giving a “scoliosed” appearance

• Less mesiodistal measurement than maxillary cuspid

• Cusp ridge:

• Mesial: almost horizontal

• Distal: steeper in apical direction

• Cusp tip is in line with the center of the root

• Contact areas: slightly more incisal than maxillary canines

• Mesial: incisal 3rd near mesioincisal angle

• Distal: junction of the middle and incisal 3rd

• Shorter and straighter root with sharper apex

Lingual

• Crown and root are narrower than the labial surface

• Flatter surface

• Poorly developed cingulum 

• Lingual and marginal ridges are not prominent along with the fossae

• Lingual ridge is less distinct except near the cusp tip, where it  is raised

• Root tapers lingually, narrowing down to a little more than half of the labial width

Proximals

• Wedge-shaped crown but thinner and less bulky

• Outline:

• Labial: less curvature, crest is more cervical 

• Lingual: flattened and low cingulum

• Cervical line: more prominent curve on the mesial vs distal, mandibular vs maxillary

• Root: more pronounced developmental depression on the distal

• mesial depression is deeper on the mandibular

Incisal

• Mesial outline is less curved

• Cusp tip and mesial cusp ridge are more likely to be inclined in a lingual direction

• Distal cusp slope is lingual to cusp tip

• Distolingual twist vs a more straight cusp ridge on the maxillary

• Cingulum is centered or slightly more distal