The maxillary lateral incisors are a pair of upper (

maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. T ...

ry)

teeth A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, t ...

that are located laterally (away from the midline of the

face The face is the front of an animal's head that features the eyes, nose and mouth, and through which animals express many of their emotions. The face is crucial for human identity, and damage such as scarring or developmental deformities may aff ...

) from both

maxillary central incisor The maxillary central incisor is a human tooth in the front upper jaw, or maxilla, and is usually the most visible of all teeth in the mouth. It is located mesial (closer to the midline of the face) to the maxillary lateral incisor. As with all i ...

s of the mouth and medially (toward the midline of the face) from both

maxillary canine In human dentistry, the maxillary canine is the tooth located laterally (away from the midline of the face) from both maxillary lateral incisors of the mouth but mesial (toward the midline of the face) from both maxillary first premolars. Both t ...

s. As with all

incisor Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, wher ...

s, their function is for

shearing Sheep shearing is the process by which the woollen fleece of a sheep is cut off. The person who removes the sheep's wool is called a '' shearer''. Typically each adult sheep is shorn once each year (a sheep may be said to have been "shorn" or ...

or cutting food during mastication, commonly known as chewing. There are generally no

cusp A cusp is the most pointed end of a curve. It often refers to cusp (anatomy), a pointed structure on a tooth. Cusp or CUSP may also refer to: Mathematics * Cusp (singularity), a singular point of a curve * Cusp catastrophe, a branch of bifurc ...

s on the teeth, but the rare condition known as talon cusps are most prevalent on the maxillary lateral incisors. The surface area of the tooth used in eating is called an incisal ridge or incisal edge. Though relatively the same, there are some minor differences between the

deciduous In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, ...

(baby) maxillary lateral incisor and that of the permanent maxillary lateral incisor. The maxillary lateral incisors occlude in opposition to the

mandibular lateral incisor The mandibular lateral incisor is the tooth located distally (away from the midline of the face) from both mandibular central incisors of the mouth and mesially (toward the midline of the face) from both mandibular canines. As with all incisors, ...

Notation

In the

universal system of notation The Universal Numbering System, sometimes called the "American System", is a dental notation system commonly used in the United States. Most of the rest of the world uses the FDI World Dental Federation notation, accepted as an international st ...

, the deciduous maxillary lateral incisors are designated by a letter written in uppercase. The right deciduous maxillary lateral incisor is known as "D", and the left one is known as "G". The international notation has a different system of notation. Thus, the right deciduous maxillary lateral incisor known as "52", and the left one is known as "62". Maxillary lateral incisors01-01-06

In the universal system of notation, the permanent maxillary lateral incisors are designated by a number. The right permanent maxillary lateral incisor is known as "7", and the left one is known as "10". In the

Palmer notation Palmer notation (sometimes called the "Military System" and named for 19th-century American dentist Dr. Corydon Palmer from Warren, Ohio) is a dental notation (tooth numbering system). Despite the adoption of the FDI World Dental Federation notat ...

, a number is used in conjunction with a symbol designating in which quadrant the tooth is found. For this tooth, the left and right lateral incisors would have the same number, "2", but the right one would have the symbol, "┘", underneath it, while the left one would have, "└". The FDI notation has a different numbering system than the previous two, and the right permanent maxillary lateral incisor is known as "12", and the left one is known as "22".

Development

The primary tooth will begin to show signs of development between 14 weeks and 16 weeks in utero, at an average of 16 weeks. The permanent tooth typically will erupt between when the child is 8 or 9 years old, while the root will continue to mineralize until around 11 years old. The tooth's crown will conclude its development around the age of 4 or 5. The upper lateral incisor is made of 4 lobes of calcification (3 labial will give rise to mamelons and 1 lingual give rise to cingulum). When the middle labial lobe is missing the mesial and distal labial lobes will bend on each other creating what is called "peg shaped laterals". Treatment usually include buildup by composite or a fixed crown restoration. The upper laterals are the 2nd most varied teeth, after the 3rd molars. They can be peg shaped, twisted crown and roots, and sometimes missing.

Deciduous dentition

There are two maxillary lateral incisors in the deciduous dentition. The teeth have a more curved distoincisal angle than the primary maxillary central incisor. The tooth is longer cervicoincisally than it is mesiodistally. The average length of the primary lateral incisor is 15.8 mm, with the average crown length being 5.6 mm and the root length average being 11.4 mm. All primary teeth have several characteristics that are different when compared to the permanent dentition. The primary lateral incisor crown is wider mesiodistally than the permanent tooth and the roots of the primary lateral incisors are longer than the permanent tooth. The cervical ridges in all of anterior teeth are more prominent than in the

Permanent dentition

There are two maxillary lateral incisors in the permanent dentition, which begin to show signs of development at 10 to 12 months after birth. The maxillary lateral incisor resembles the

, but is smaller in every dimension aside from root length. The root of the lateral incisor is around 1.5 times the length of the crown. The tooth has the most variability in crown shape in the mouth except the

maxillary third molar A third molar, commonly called wisdom tooth, is one of the three molars per quadrant of the human dentition. It is the most posterior of the three. The age at which wisdom teeth come through ( erupt) is variable, but this generally occurs betwe ...

. The two lateral incisors can also be congenitally missing. The teeth are less pigmented and are whiter in appearance than the permanent teeth.

Labial aspect

Compared to the maxillary central incisor, the maxillary lateral incisor has more rounded mesial and distal incisal angles. The distal outline is always more rounded. The root is often tapered distally, often with a sharp curve distally and to an apex; however, the curve can be absent. The mesial and distal contacts are more cervical than the central incisor. The surface is smooth. The labial view of the lateral incisor fits into the geometric shape of a trapezoid.

Lingual aspect

The distal and mesial marginal ridges are evident and the cingulum is prominent. The lingual fossa is more concave than the central incisor. The cingulum will often have a deep developmental groove on the distal side that can continue well into the root. The lingual view of the lateral incisor fits into the geometric shape of a trapezoid.

Mesial aspect

The curvature of the

cementoenamel junction The cementoenamel junction, frequently abbreviated as the CEJ, is a slightly visible anatomical border identified on a tooth. It is the location where the enamel, which covers the anatomical crown of a tooth, and the cementum, which covers the ...

(CEJ) or the cervical line sharply inclines towards the incisal ridge. The mesial view of the lateral incisor fits into the geometric shape of a triangle.

Distal aspect

Compared to the tooth's mesial view of the cervical line, the distal cervical line is slightly more cervical by close to a millimeter. There may be a developmental groove present for all or most of the length. The distal view of the lateral incisor fits into the geometric shape of a triangle.

References

Citations Bibliography * * {{Tooth anatomy Types of teeth Human mouth anatomy