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Premolar, Dyandra Wirahana Hasan - 2106717682, BDS CL 6 - Coggle Diagram

- - - - The buccal outline of the crown curves outward below the cervical line
      - Well-defined developmental groove in the enamel of the mesial marginal ridge
      - Cervical portion is longer than the occlusal portion
      - Long tooth trunk
      - Shape of the crown is roughly trapezoidal
    - - The crown surface is convex at all points at all points except for a small, flattened arc just cervical to the contact area and buccal to the center of the distal surface
      - Less curvature of the cervical line than the mesial
      - If there’s developmental groove, it should be shallow and insignificant
      - Flattened root trunk above the cervical line
    - - Pointy cusp tip
      - Mesial and distal outlines of the crown are convex
      - The lingual cusp is narrower mesiodistally than the buccal cusp
      - Shorter cusp than the buccal cusp
      - Smooth and convex root at all points
      - The apex of the root is more blunt than the buccal root apex
    - - Resembles a (non-equilateral) hexagonal figure
      - Distance from the mesial crest to the lingual crest is much shorter than the distance from the distal to the lingual crest
      - Wider crown on the buccal than lingual
      - Greater buccolingual dimension than mesiodistal
    - - Has little curvature the cervical line of the crown
      - The mesial slope of the buccal cusp is rather straight and longer than the distal slope
      - The crown is roughly trapezoidal
      - Has straighter distal outline on the crown below the cervical line than that of the mesial
      - The roots are 3 or 4 mm shorter than those of the maxillary canine
      - The surface is convex
      - long and Pointy buccal cusp
- - - - less pointy if compared with maxillary1st premolar
      - The mesial slope of buccal cusp ridge usually shorter than the distal slope
      - Trapezoidal crown
      - Buccal ridge less developed and not as prominent as first premolar
      - has conical root
      - The crown and root are thicker at the cervical portions
    - - Buccal and lingual cusps are closer to same length
      - occlusal surface are not visible
      - Trapezoidal crown
      - the lingual tip are sharper
      - Mesial cusp ridge are shorter the distal on buccal cusp
    - - Greater distance between cusp tips widened the occlusal table
      - No developmental depression evident on the mesial surface of crown, the crown surface is convex
      - Trapezoidal crown
      - Single root
    - - Straight rather than curved cervical line
      - Distal contact area at the same level with mesial contact area
      - Distal root depression deeper than mesial depression
      - The lingual and buccal cusp are shorter and nearly at the same level, greater distance between the two
    - - Outline of the crown is more rounded than angular
      - Buccal lines are not prominent
      - Lingual buccal dimension is more than distal side
      - Central development groove is shorter and more irregular
      - Less lingual curvature due to lingual and buccal cusp nearly at the same level
- - - - From the mesial aspect, the mandibular first premolar shows an outline that is the same as all mandibular posterior teeth when viewed from the mesial or distal aspect
      - The crown outline is roughly rhomboidal
      - The tip of the buccal cusp is nearly centered over the root.
      - The mesiobuccal lobe development is prominent from this aspect
      - the buccal outline is marked by convex from cervix to buccal cusp tip
      - Occlusal outline is a concave arc sloping lingually
      - the cervical line curves slightly in the occlusal direction
      - the buccal cusp tip is centered over the root base. In other words, it is in line with the vertical root axis
      - Mesial contact area: It is occlusal to the center of crown, and is in line with the buccal cusp tip.
      - The mesial surface of the root is smooth and flat from the buccal margin to the center. From this point, it too converges sharply toward the root center lingually, often displaying a deep developmental groove in this area
    - - Rhomboidal
      - the distal surface is smooth except for a small linear concavity just above the cervical line
      - The distal surface is a little shorter occlusocervically, and it is wider buccolingually than the mesial surface.
      - The distal contact area is broader than the mesial, although it is centered in the same relation to the crown out- lines.
      - A shallow developmental depression is centered on the root, but rarely does it contain a deep developmental groove.
    - - The crown of the mandibular first premolar tapers toward the lingual
      - Lingual measurement mesiodistally is less than that buccally
      - The mesial and distal surfaces of both may be seen from the lingual aspect because the crown and the root narrows toward the lingual
      - Have mesiolingual developmental groove (between the mesiobuccal lobe and the lingual lobe and extends into the mesial fossa of the occlusal surface)
      - The root of this tooth is much narrower on the lingual side
    - - Diamond shaped or circular
      - buccolingual is greater by 0,5 mm than the mesiodistal
      - cusp: 2 → buccal cusp is larger making the major bulk of the crown and the lingual cusp is much smaller
      - fossa : 2 → mesial and distal
      - grooves : 3
      - mesial developmental groove → It is located in the mesial fossa; is short and extends buccolingually
      - distal developmental groove → It is in the distal fossa is longer
      - mesiolingual developmental groove → continuous from mesial groove and it extends between mesial marginal ridge and mesiolingual cusp ridge onto the lingual surface mesially. this groove is the characteristic feature of mandibular 1st premolar.
    - - Symmetrical bilaterally
      - The middle buccal lobe is well developed, which results in a large, pointed buccal cusp
      - Curvature at the cervical line buccally is little
      - The mesial outline of the crown is straight or slightly concave above the cervical line to a point where it joins the curvature of the mesial contact area
      - The tip of the buccal cusp is pointed and in most cases it is located a little mesial to the center of the crown buccally
      - In general, the enamel of the buccal surface of the crown is smooth and shows no developmental grooves and few developmental lines.