Primary Dentition week 5

week 5

Primary teeth are smaller overall than

their permanent successors

The crown of any primary tooth is

is short in relation to its total length.

Primary teeth color

lighter in color than the permanent teeth.They have a whiter color with a bluish cast.

Permanent teeth color

yellow, gray, or brown tones.

A prominent cervical ridge is present on the anterior teeth

labially and lingually.

The buccal cervical ridges on the primary molars are much more

pronounced, especially on the first molars.

The buccal and lingual surfaces of primary molars taper 

occlusally above the cervical ridges much more than the permanent molar buccal and lingual surfaces. This results in a much narrower occlusal table buccolingually.

The buccal and lingual grooves stay

within the occlusal table.

Primary molars are wider

mesiodistally than the permanent premolars, which will take their places.

The roots of primary anterior teeth are

narrower and longer as compared with the permanent teeth roots.

The roots of the primary molars are longer and more slender than the roots of the permanent teeth. 

These roots also flare apically to allow room in between for the developing crowns of the permanent teeth.

The roots of primary posterior teeth are very narrow at their

cementoenamel junctions (CEJ) where the crowns join the roots

the root trunks of primary molars are very

short

The pulp chambers of primary teeth are relatively

large in comparison with the crowns that envelop them.

The pulp horns of primary teeth extend rather high

occlusally, placing them much closer to the enamel than the pulp horns in permanent teeth.

The dentin thickness between the pulp chambers and the enamel of primary teeth is 

much thinner than in permanent teeth.  However, this thickness increases gradually.

The enamel of primary teeth is relatively thin and has a consistent

Thickness

The enamel of primary teeth is

opaque and does NOT reflect dentin

Primary teeth total

20 total when the primary dentition period is completed

How many primary teeth per arch

10 per arch

Primary dentition tooth types

incisors, canines, and molars

Mineralization of the primary teeth begins in utero at

13 to 16 weeks

cervical ridge

These bulky ridges extend out from the very narrow cervical necks of the teeth.

These cervical prominences give primary crowns a

bulbous appearance and accentuate the narrow cervical portion of primary teeth.

The enamel of permanent teeth is

translucent reflecting the dentin underneath it

prenatally, all primary teeth have started to mineralize

18 to 20 weeks

Is there teeth visible in the oral cavity at birth?

NO

First eruption of a primary tooth is a

primary mandibular central incisor

First eruption occurs at

6 to 10 months

How long does it take for primary dentition to be completed?

2 to 3 years

Space is necessary in primary teeth for

proper alignment of the future permanent dentition

Primate spaces

Spaces between the primary maxillary later incisor and canine, and also between the primary mandibular canine and first molar

permanent molars erupt

distal to the primary second molars

A child’s first dental appointment should occur within

6 months of eruption of the first primary tooth and no later than 12 months of age

baby bottle tooth decay

early childhood caries

Primary Maxillary Central Incisor E & F (#51 & #61)

. Wider MD than IC (only anterior w/ this crown dimension)

.Mesial/ Distal outlines are more rounded

. Crown appears thick even at the incisal third

. Single root is round and tapers evenly to the apex, but it’s longer relative to crown length

Primary Maxillary Lateral Incisor D & G (#52 & #62)

. Crown is smaller in all dimensions

. Longer IC than MD

. Incisal angles are more rounded than the central

. Longer root, apex is sharper

Primary Mandibular central incisor O&P (#71 & #81)

. Symmetrical similar to it’s permanent successor

.Smooth lingual surface that tapers toward the prominent cingulum

.Less pronounced marginal ridges than primary maxillary incisor

.Lingual fossa is shallow

. Root is single long and slender

. Labial and lingual surfaces are rounded

. Proximal surfaces are slightly flattened

Primary Mandibular Lateral Incisor N & Q (#72 & #82)

. Crown wider and longer than central

. Incisal ridge slopes distally and it’s DI angle is more rounded

. Not as symmetrical

. The root may have distal curvature in it’s apical third, distal longitudinal groove