PERMANENT MAXILLARY CENTRAL INCISORS GENERAL FEATURES Permanent incisors

PERMANENT MAXILLARY CENTRAL INCISORS

GENERAL FEATURES • Permanent incisors are eight in number; four in the maxilla and four in mandible. • Incisors include two central incisors and two lateral incisors in maxilla and mandible each. • Central incisors are located on either side of the midline • Lateral incisors are situated distal to it • As the name indicate the incisors function in incising or cutting food. • These teeth are also important in articulation of speech and esthetics.

INTRODUCTION 2 in number on either side of midline Most prominent teeth Central incisors also known as first incisors Widest teeth in anterior segment

Median line Central incisor Lateral incisor

LABIAL ASPECT Crown appears smooth and convex, Shape is squarish or rectangular Mamelons seen in newly erupted teeth Sharp mesioincisal angle and rounded distoincisal angle Distal outline is more convex Single root tapering to a somewhat blunt apex Cervical line- towards root

LABIAL ASPECT Outlines from the labial aspect Mesial outline is slightly convex with contact area (crest of curvature) at the incisal third close to the mesio-incisal angle. Distal outline is more convex than mesial out line and contact area is located at the junction between middle and incisal third.

LABIAL ASPECT Outlines from the labial aspect Cervical outline is semicircular with curvature towards the root Incisal outline is represented by incisal edge which is straight and regular with sharp mesio-incisal angle and slightly rounded disto-lingual angle. Labial surface of is smooth Surface becomes relatively flat as the incisal edge is approached.

Maxillary central incisor Distoincisal angle Mesioincisal angle

PALATAL/LINGUAL ASPECT Shows concavities and convexities Lingual fossa is seen Convexity - cingulum on cervical 3 rd of crown Lingual fossa is bounded by cingulum superiorly, mesial and distal marginal ridges laterally and by the incisal ridge inferiorly Mesial and distal sides of root converges lingually Cervical line- towards root

PALATAL/LINGUAL ASPECT Convexities: There is a convex area called cingulum located at the cervical third Either side of the lingual aspect is bordered by linear elevations called marginal ridges. The ridge on mesial side is called mesial marginal ridge and is slightly longer than the distal marginal ridge The lingual surface also shows the presence of lingo-incisal ridge, which forms the incisal boundary of the lingual surface

PALATAL/LINGUAL ASPECT Concavity: The major portion is occupied by a concavity called lingual fossa. The lingual fossa is ‘M’ shaped and is bounded superiorly by the cingulum, inferiorly by the linguo-incisal ridge and on either side by the mesial and distal marginal ridges A deep developmental groove may be present on the lingual surface extending on to the cingulum.

cingulum Mesial Marginal ridge Lingual fossa DISTAL MARGINAL RIDGE

MAX CENTRAL INCISOR-MESIAL ASPECT Crown appears triangular with base at cervical region and apex at incisal edge Labial outline is convex with crest of curvature at cervical 3 rd Lingual outline is convex in cervical 3 rd, concave in middle 3 rd and convex at incisal ridge Curvature of cervical line towards incisal tip is more convex on mesial side

MAX CENTRAL INCISOR-MESIAL ASPECT The incisal edge and the root tip lies in the midline which bisects the tooth. Cervical outline is curved with curvature towards the crown. Mesial surface of central incisor is smooth and convex. Root is cone shaped, tapered with a rounded apex.

MAX CENTRAL INCISOR-MESIAL ASPECT Increased curvature of cervical line Triangle shaped crown

MAX CENTRAL INCISOR-DISTAL ASPEC Similar to that of mesial aspect Curvature of cervical line towards incisal aspect is less pronounced The Crown appears to be boarder from this aspect than the mesial aspect. The root is tapered towards the rounded apex

MAX CENTRAL INCISOR-DISTAL ASPECT Reduced curvature of cervical line

MAX CENTRALINCISOR-INCISAL ASPECT Appears convex near the cervical line Marked convexity of cingulum on lingual aspect

MAX CENTRAL INCISORINCISAL ASPECT Shape of the maxillary central incisor is triangular from this aspect With the base on the labial surface and the apex towards the cingulum. The mesio-distal dimension is greater than the labio-lingual dimension.

MAX CENTRAL INCISORINCISAL ASPECT As the incisal edge is straight and is located at the center, equal extent of the labial and lingual halves can be seen. The lingual fossa, marginal ridges and distally placed cingulum can be appreciated Root can not be appreciated from this aspect because it is superimposed on the crown.

MAX CENTRAL INCISORINCISAL ASPECT

Maxillary central incisor morphology