Permanent Maxillary Central & Lateral Incisors PDF

Permanent maxillary central & lateral Maxillary central incisor Maxillary lateral incisor Enamel organ appearance 5 MIUL 5 MIUL Beginning of calcification 3-4 months old...

Permanent maxillary central & lateral Maxillary central incisor Maxillary lateral incisor Enamel organ appearance 5 MIUL 5 MIUL Beginning of calcification 3-4 months old 10-12 months old Crown completion 4-5 years old 4-5 years old Eruption 7-8 years old 8-9 years old Root completion 10-11 years old 11 years Mesial outline Slightly convex Slightly convex (more convexity than (with sharp mesioincisal angle) the central’s) (with rounded mesioincisal angel) Mesial contact area Close to the mesioincisal angle At the incisal/middle junction. It’s larger &wider than the distal one Distal outline More convex than the mesial Even more convex (with a rounded distoincisal angle) (with rounded distoincisal angle) Distal contact area At the incisal/middle junction At the center of the middle third (narrower than the mesial one) Labial outline (proximal view) Convex, with the maximum convexity on The same as the central’s but more the cervical third convex and has more prominent cervical ridge Lingual outline (proximal view) Convex at the cervical third, then The same as the central’s with more concave until the incisal ridge where it’s prominent cingulum slightly convex. Labial outline (incisal view) Broad & flat More convex than the central’s Lingual outline (incisal view) Narrow because of the convergence of The same with more convexity than mesial & distal side at the cingulum the central’s *thus, more rounded incisal view (ovoid in shape) * The root labial & lingual views: labial & lingual views: -Cone shaped (tapering) with blunt apex -Cone shaped & slender (compressed -less likely incline distally mesiodistally) with pointed apex. -more likely incline distally proximal view: proximal view: -Cone shaped with the labial outline Tapers to a blunt apex straighter than the lingual one. Pulp cavity (chamber & canal) *Follows the configuration of the crown *the same as the central’s. but in some & the root* specimens the incisal end of the mesiodistal section: chamber is rounded rather than the -Wide pulp chamber presenting 3 pulp three pulp horns horns. -The chamber is wide till the cervical line where it tapers towards the apical foramen forming the root canal labiolingual section: -pointed towards the incisal edge then widens till the cervical line then tapers… forming the root canal cross section at the cervix: -circular & centered in the root -or triangular because of the lingual convergence (in the young) features -Mesiolabial & distolabial shallow DGs -also has ML & DL DGs -less prominent elevations & depressions -more prominent … -larger shallow lingual fossa -smaller but deeper lingual fossa -lingual pit is less common -lingual pit is more common -deep developmental groove near the cingulum on the lingual fossa -another DG distal to the cingulum which may extend on most of the root’s length (not common) -tubercle may exist as a part of the cingulum -a lot other variations may occur as twisted roots or may be missing