LABIAL ASPECT
-Crown : Narrower misodistatlly than those of maxillary central incisor
-Labial Ridge : Shallow depression mesially and distally present dividing the 3 labial lobes and middle lobe shows much greater development than other lobes
-Cervical line : Convex with convexity towards root portion
-Mesial outline : May be convex from the cervix to the centre of the mesial contact area
-Distal outline : Concave from the cervix to the distal contact area
-Cusp tip : It is on line with the center of the root
-Mesial slope of cusp is shorter than distal slope
-Root: It is narrower mesiodistally
: Smooth and convex in all directions
: It appears slender in form with 2 bluntly pointed apex
LINGUAL ASPECT
-Crown : Narrower lingually than labially
-Cervical line : The line may be start for short interval at this point
-Cingulum : Large and pointed all a small cusp
-Definate ridges are found below the cingulum b/w stronly developed marginal ridges
-Fossa : 2 lingual ridges and the marginal ridge
-Root : Narrower than the labial portion
MESIAL ASPECT
-Greater bulk and greater labiolingual dimension
-Crown : Wedge shaped
: Greater dimension than distal
:Wedge point represented by the cusp tip
-Crest of curvature : more incisally
-Labial outline : Exhibits convexity from the crest of curvature at the cervical third, which straightens as it approaches the cusp tip
-Lingual outline : It represent convex line describing the cingulum which straightens out as the middle third is reached and it becomes covex in the incisal third
-Cervical line : Curves towards the cusp on average by approx 2.5 mm at the CEJ
-Root :Conical with tapered or blunt pointed apex
:Curves labially towards the apical third
:Root appears board with 2 shallow developmental depression for most of the part of root length
:Line bisecting the cusp is labial to line bisecting the root
:Mesial surface of the crown present convexities at all point except for a small circumscribed area above the contact area , where the surface is concave and flat b/w the area and cervical line
DISTAL ASPECT
-Cervical line : exhibits less curvature towards the cusp ridges
-Distal marginal ridges : It is heavier and more irregular in outline
-Developmental depression : Is more pronounced on the distal side of the root
INCISAL ASPECT
-Tip of the cusp : It is labial to the centre of the crown labiolingually and mesial to the center mesiodistally
-There is entire distal portion stretched to make contact with the first premolar
-The ridge of the middle labial lobe is very noticeable labially from incisal aspect
-Greater convexity at the cervical third of the crown and becoming broader and flatter at the middle and incisal third
-Outline of the cingulum : A shorter arc
-A line bisectiong the cusp and cusp ridge drawn in the mesiodistal direction is almost always straight and bisects the short arc representing the mesial and distal contact areas
-Crown : Narrower misodistatlly than those of maxillary central incisor
-Labial Ridge : Shallow depression mesially and distally present dividing the 3 labial lobes and middle lobe shows much greater development than other lobes
-Cervical line : Convex with convexity towards root portion
-Mesial outline : May be convex from the cervix to the centre of the mesial contact area
-Distal outline : Concave from the cervix to the distal contact area
-Cusp tip : It is on line with the center of the root
-Mesial slope of cusp is shorter than distal slope
-Root: It is narrower mesiodistally
: Smooth and convex in all directions
: It appears slender in form with 2 bluntly pointed apex
LINGUAL ASPECT
-Crown : Narrower lingually than labially
-Cervical line : The line may be start for short interval at this point
-Cingulum : Large and pointed all a small cusp
-Definate ridges are found below the cingulum b/w stronly developed marginal ridges
-Fossa : 2 lingual ridges and the marginal ridge
-Root : Narrower than the labial portion
MESIAL ASPECT
-Greater bulk and greater labiolingual dimension
-Crown : Wedge shaped
: Greater dimension than distal
:Wedge point represented by the cusp tip
-Crest of curvature : more incisally
-Labial outline : Exhibits convexity from the crest of curvature at the cervical third, which straightens as it approaches the cusp tip
-Lingual outline : It represent convex line describing the cingulum which straightens out as the middle third is reached and it becomes covex in the incisal third
-Cervical line : Curves towards the cusp on average by approx 2.5 mm at the CEJ
-Root :Conical with tapered or blunt pointed apex
:Curves labially towards the apical third
:Root appears board with 2 shallow developmental depression for most of the part of root length
:Line bisecting the cusp is labial to line bisecting the root
:Mesial surface of the crown present convexities at all point except for a small circumscribed area above the contact area , where the surface is concave and flat b/w the area and cervical line
DISTAL ASPECT
-Cervical line : exhibits less curvature towards the cusp ridges
-Distal marginal ridges : It is heavier and more irregular in outline
-Developmental depression : Is more pronounced on the distal side of the root
INCISAL ASPECT
-Tip of the cusp : It is labial to the centre of the crown labiolingually and mesial to the center mesiodistally
-There is entire distal portion stretched to make contact with the first premolar
-The ridge of the middle labial lobe is very noticeable labially from incisal aspect
-Greater convexity at the cervical third of the crown and becoming broader and flatter at the middle and incisal third
-Outline of the cingulum : A shorter arc
-A line bisectiong the cusp and cusp ridge drawn in the mesiodistal direction is almost always straight and bisects the short arc representing the mesial and distal contact areas
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