Maxillary Central Incisor

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MAXILLARY CENTRAL INCISOR

Introduction

* Centre in the maxilla , one on either side of the median line, with mesial surface of each in contact with mesial surface of other.
* Two in number.
* Larger than lateral incisor.
* These teeth supplementary to each other in function, and they are similar anatomically.
* Shearing and cutting teeth .
* Major function is punch and cut food material during the process of mastication.

CONTACT AREA
Mesial - Incisal third very near or approaching in the Incisal angle .
Distal - Near the junction of Incisal and middle third .


LABIAL ASPECT

* Crown outline is trapezoidal.

* Length of crown is usually greater than mesiodistally width.

* Outline of crown -
# mesial slightly convex.
# distal outline more convex. 

* Mesio-incisal angle is sharp , Disto-incisal angle rounded.

* Incisal outline regular and straight in mesiodistal direction .

* Root is cone shape with a regularly blunt apex .

LINGUAL ASPECT

* Smooth convexity at the cervical third , cingulum is located off centered towards distal.

* Between mesial and distal marginal ridge is a swallow concavity , the lingual fossa .

* Linguoincisal  edge is riased, in level with Marginal Ridge.

* There are developmental groove extending from cingulum to the lingual fossa.

* Crown and root tapered lingually.

* Root surface on lingual is narrow than labially.

MESIAL ASPECT

* Crown is triangular and wedge shaped.


* Root axis line bisect Incisal ridge and root apex, Incisal ridge is in line with the center of root.

* Crest of curvature at the cervical third - greatest labio-lingual measurement .

* CEJ curves incisally to a noticeable degree than any of the tooth in tha mouth.

* Root is cone shaped apex is usually bluntly  rounded.

DISTAL ASPECT

* Similar to mesial ; except crown is thicker toward Incisal 3rd.

* Less curvature of CEJ.

INCISAL ASPECT

*Labial surface is relatively broad and flat especially towards incial 3rd .

* Cervical portion of crown is convex arc is described as broad .

*Incisal ridge slope towards lingual .

* Lingual outline - tapered towards cingulum.

* Cingulum off  centered to the distal.

* Prominent mesiolabial and distolabial  line angle. 



ROOT


* The root is single, conical, relatively straight, and tapers to rounded apex.

* Normally , the root is  wider at labial, which  is the base of triangle and narrower at lingual which is apex.

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