Dental Anatomy: Permanent Canines

Permanent Canines

• Canines are designed to tear and hold food.
• They are the cornerstone of the dental arch.
• They contribute to the aesthetics and stability of the mouth.
• They are the longest teeth and roots in the mouth.
• The initiation of development is 4-5 months.
• The completion of enamel development is 6-7 years.
• Eruption: Maxillary – 11-12 years, Mandibular – 9-10 years.
• Root completion: Maxillary – 13-15 years, Mandibular – 12-14 years.
• Maxillary numbering system: Universal – 6, Left – 11, Palmer – 3, International - 13.
• Mandibular numbering system: Universal – 22, Left – 27, Palmer – 3, International – 33.
• Maxillary canine crown: Convex with a pronounced middle labial ridge. Mesial slope is shorter than distal, sharp cusp tip. Prominent esthetic and functional role.
• Maxillary canine lingual surface: Concave with well-developed anatomy. Features: prominent cingulum, marginal ridges and fossae. Deep grooves are prone to decay.
• Maxillary canine mesial surface: Triangular with well-defined CEJ curvature. Features: contact area at the junction of the incisal and middle thirds.
• Maxillary canine distal surface: Similar to the mesial but more convex. Features: contact area located in the middle third.
• Maxillary canine incisal edge: Asymmetrical diamond-shaped outline. Cusp tip is centered labiolingually and slightly mesial to the center. Mesial appears bulkier than the distal. Pronounced labial ridge is visible. Labiolingual width is greater than mesiodistal. Provides tearing and guiding functions in occlusion.
• Maxillary canine root features: Long, conical, tapering towards the apex. Oval cross section, possible longitudinal grooves. Long root ensures stability.
• Maxillary canine dimensions: Crown length – 10 mm, Root length – 17 mm, Mesiodistal diameter – 7.5 mm, Labiolingual diameter – 8 mm.
• Maxillary canine clinical relevance: Impaction and Eruption challenges. The maxillary canine is the second most frequently impacted tooth after third molars. This occurs due to its long eruption path and delayed eruption compared to other teeth. Impaction may require orthodontic or surgical intervention. Esthetic and functional importance. Plays a crucial role in smile esthetics due to its prominent position and unique shape. Contributes to facial symmetry and support for the upper lip. Guidance in occlusion. Acts as a cornerstone of the arch, providing canine guidance during lateral movements of the jaw. Protects posterior teeth from excessive wear during excursive movements. Periodontal concerns. Pronounced labial convexity and prominent cingulum can make plaque removal challenging. Restorative challenges. Large, prominent roots require careful endodontic treatment. Restorative or prosthetic work should preserve the canine’s esthetic and functional integrity.

Mandibular Canines

• Mandibular canine abutment for prothetics: Strong and well-anchored roots make mandibular canines excellent abutments for bridges and removable partial dentures.
• Mandibular canine root morphology challenges: Roots are often curved distally and may have longitudinal grooves, complicating root canal therapy and extraction. Bifurcated roots are rare but possible, adding to complexity during treatment.
• Mandibular canine wear patterns: More prone to wear due to involvement in lateral movements, less prominent cusp tips. Occlusal wear may flatten the cusp over time, requiring monitoring in older patients.
• Mandibular canine esthetics: Less critical to esthetics than maxillary canines.
• Mandibular canine orthodontic considerations: Often used as anchor points in orthodontic treatments due to their strong root structure.

General

• Both maxillary and mandibular canines are essential for guiding the bite.
• Maxillary canines play a more prominent role due to a longer root and more pronounced cusp.