1- They are placed in the corner of the mouth, which help in keeping facial expression, and they are between incisors and the premolars , and have a cosmetic values.
2- They are the longest teeth in the mouth.
3- They are the most stable teeth in the mouth because:
a) Large labiolingual thickness of the tooth.
b) Long roots are anchored well in the alveolar bone.
c) The crown’s shape promotes cleansiness so they are less prone to caries.
4- The middle labial lobe is highly developed incisally into a strong well formed cusp.
5- They are the strongest teeth in the mouth.
Principle identifying features
1- Single pointed cusp.
2- Distal slope of the cusp is longer than the mesial slope.
3- Marked convex labial outline and bulky palatal cingulum.
4- Very long single root.
1- The mesial outline of the crown is convex, with the crest of curvature at the junction of the incisal and middle thirds.
2- The distal outline of the crown is slightly concave from the cervical line to the crest of curvature which is at the centre of the middle third.
3- The distal slope of the cusp is longer than the mesial slope.
4- The cervical line is convex, with the convexity towards the root portion.
5- The labial surface of the crown is smooth except for shallow depressions mesially and distally dividing the three labial lobes. The middle lobe is much more developed producing the labial ridge.
6- The root is long, conical, and the apex is distally curved.
1- The tooth is narrower lingually than labially.
2- The cingulum is larger than the max. incisors.
3- A well developed lingual ridge confluent with the cusp tip, which divides the lingual fossa is two fossae.
4- There are developmental depressions mesially and distally extending for most of the root length.
1- The labial and lingual outlines of the crown are more convex than the max. incisors, with the crest of curvature (labially & lingually) at the cervical third.
2- The cervical line curvature is 2.5mm.
3- A line bisecting the cusp is labial to a line bisecting the root.
4- There is a shallow developmental depression on part of the root.
1- The cervical line curvature is less distally than mesially.
2- The developmental depression of the root is more pronounced.
1- The labiolingual dimension is greater than the mesiodistal.
2- The ridge of the middle labial lobe is very noticeable labially. It’s greatest convexity is at the cervical third, and a sit reaches the cusp tip it becomes flatter.
3- The cingulum is well developed and makes a small arc when compared with the labial outline which is a big.
4- The cusp tip is labial to the centre labiolingually, and mesial to the centre mesiodistally.
Principle Identifying Features
1- The tooth is narrower mesiodistally and labiolingually than max. canine.
2- The lingual surface of the crown is smoother, with less cingulum development and less bulk to the marginal ridges than the max. canine.
3- The cusp is not as well developed as max. canine, and the cusp ridges are thinner labiolingually.
4- The cusp tip is on a line with the centre of the root, from the mesial or distal aspect.
5- The mesial slope of the cusp is shorter than the distal slope.
6- The distal outline of the crown is more rounded than the mesial.
7- The mesial surface of the crown is nearly straight with the mesial surface of the root, the contact area being near the mesioincisal angle.
8- The distal contact area is more towards the incisal than the max. canine
Difference between the maxillary canine and maxillary first premolar:
Subject ... Canine ... First Premolar
1- Contact area ... Different level ... Nearly same level
2- Length ... Long tooth ... Shorter tooth
3- Cusps ... One cusp ... Two cusps
4- Roots ... One root, and root canal ... Two roots, and root canals
5- Cusp Slopes ... Distal slope is longer ... Mesial slope is longer
6- Width of the crown ... Labio-lingual comparable ... Labio-lingual longer than mesio- with mesio-distal distal
7- Marginal ridge ... Not in a horizontal plane ... In a horizontal plane
8- D.G. crossing ... No ... Yes
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