Lecture 5 Flashcards
Canine function
Support lips and cheeks
• Cut, pierce, or shear food
• Protect (separate) posterior teeth during mandibular movements resulting in canine- protected occlusion
Maximal intercuspal position
In maximal intercuspal position posterior teeth come in contact and act as stops to minimize horizontal load on anterior teeth. Anterior teeth guide all the other movements of the mandible so posterior teeth contact will not take place during lateral or protrusive movements.
Canine shape/size
Pentagon, largest in each arch - maxillary canine is the longest in the mouth, coupled with long roots as well.
Maxillarycanineroots
have a sharp apex and are more likely to bend distally at apex than mandibular
Mandibular apex
More blunt, rare bending.
Lingual ridge in canines
More prominent in maxillary canine - with mesial and distal fossae. Extends from cingulum to cusp tip/apex.
Canine wear
Mandibularincisal ridges wear more on labial half of incisal ridge, whereas maxillary wear more on lingual (seen best from proximal views)
Differentiate between canine and incisor
Wear pattern, root size, incisal edge with respect to midaxis. Crown is longer facially-lingually than mesially-distally.
Cingulum -canine
Larger on maxillary than mandibular. Location is important. Maxillary has cingulum centered to root axis, mandibular is distal to root axis (like mandibular lateral incisors + max central incisors).
Maxillary marginal ridges are more
prominant than mandibular
Canine roots
Both types are narrower on lingual half (maxillary incisors are the only ones w/o root depressions - which are always deeper on distal). Straight root, pointed
Bothtypesare narrower on lingual half
• Mesial and distal root concavity maybe present
Maxillary has greater root bend.
Canine Outline - proximal
Bothmaxillaryand mandibular outlines are wedge shaped (triangular) but maxillary canines are thicker
Incisal Ridge and Cusp Tip of Canines - proximal
Cusp tips of maxillary canines are more labial to midroot axis, whereas mandibular are more lingual or centered
Canine Height of Contour - proximal
In cervical third, HOC is further away from CEJ in maxillary. Meanwhile, CEJ, root in line and closer for mandibular. Maxillary is also more prominent. There is a much greater depression on maxillary at CEJ - almost like 2 convexities vs. 1 for mandibular. Maxillary also has wider faciolingual ridge.
Canine Cervical line
Both CEJ curvatures are greater on mesial than distal. Mandibular curve may appear even greater due to narrow faciolingual dimension.
Canine root
Depressions greater on distal. Mandibular is the fish tooth…
Canine crown proportions - incisal
Labiolingual greater than mesiodistal - especially in mandibular canines (narrower mesiodistally than maxillary). Distolingual twist is apparent on mandibular canines, not maxillary.
Canine cingulum and marginal ridges - incisal
Cingulum distal to center on mandibular. Mesial marginal ridge thus is longer on mandibular.
Canine labial contour - incisal
Labial outline of both canines are convex. Distal half of labial surface of maxillary canine crown is more prominently concave.
Canine lingual contour - incisal view
Lingual ridge and two lingual fossae more evident and obvious on maxillary canine.
Incisal Ridges and Cusp Tips of canines
Incisalridge(edge)is divided into mesial and distal cusp ridges forming a cusp
• Mesialcuspridgeis shorter than distal
• Facialoutlineis pentagon shaped
Canine proportions
Caninecrowns: Labiolingual greater than mesiodistal like mandibular incisors
Compared to incisors
- Distalcontactismore cervical than mesial contact
- Crownismoreconvex on distal
- Crowntapers narrower toward cervical
- Rootslongerthan crowns
Canines similar to incisors
Proximaloutlinesof crowns are wedge shaped (triangular) with lingual “S” shape
• Mesialcementoenamel junction (CEJ) has more curve than distal
• Facialandlingual height of contour on cervical 1/3
Marginalridgestaper toward cingulum (lingual half narrower than facial half)
• Fromincisal:lingual contour more curved (convex) than labial
• Rootstapertoward apex (and toward lingual)
Incisal Facet on Maxillary Canine
Diamond shaped
Canine facial surface
Facialsurfaceformed by three lobes: middle forms labial ridge, which is more prominent on maxillary canine
Mesial canine incisal edge
Mesialcrowncontour of maxillary is convex, whereas mandibular mesial contour is almost flat and nearly in line with root contour
Mandibularcanine crown
appears bent distally relative to root
Mandibular canine cusp tip
Mandibularcuspis more obtuse (more blunt)(120) with mesial cusp ridge closer to horizontal
