Eruption: 7-8 yrs

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Maxillary Central Incisors

#’s 8 & 9

Eruption: 7—8 yrs.

Root Completion: 10 yrs

  • Largest anterior tooth mesiodistally

  • Mesioincisal outline is straighter. Mesioincisal angle is sharper

  • Distoincisal outline is rounder. Distoincisal angle is rounder

  • Less convex labially than the lateral and canine at cervical 1/3.

  • Meet mesial to mesial

  • Mammelons when newly erupted

  • Mesial contact area = incisal third approaching the mesioincisal angle

  • Distal contact area = junction of the middle and incisal thirds (more incisal)

  • On the lingual: Cingulum, mesial marginal ridge, distal marginal ridge, incisal edge all are surrounding the lingual fossa

  • Mesial cervical line curves toward the incisal (curves the greatest of any other tooth in the mouth

  • Distal cervical line curves less incisially

Maxillary Lateral Incisors

#’s 7& 10
Eruption: 8-9 yrs

Root Completion: 11 yrs

  • Supplements central in function

  • Smaller in all dimensions EXCEPT for root length which is as great if not greater than the root of the maxillary central

  • Root length is greater in proportion to its crown length

  • Other than the 3rd molars, varies more in form

  • Mesioincisal outline slightly more rounder than central (still straighter than distal)

  • Distolincisal outline is more rounder

  • Mesial contact = junction of the middle and incisal thirds

  • Distal contact center of middle third, more cervical

  • Labial surface more convex than central

  • Prominent Cingulum, marginal ridges, and lingual fossa

  • Appears thicker on the distal than on the mesial

Maxillary Canines

#’s 6 & 11
Eruption: 11-12 yrs

Root Completion: 13-15 yrs
General characteristics of the permanent canines

  • All canines are the “Cornerstone” of the mouth

  • Extra bulk of bone on the labial portion of root called Canine eminence which help to support facial muscles

  • Longest root of any teeth making the canines the most stable teeth

  • In function, support the incisors and the premolars (makes for a smooth transition)

  • Longest tooth cervicoinsically


  • 4 lobes, 3 on the facial and one lingual (mesial, middle and distal)

  • Lingual lobe is the cingulum—cusp want to be

  • The largest tooth labiolingually (labiolingual dimensions is greater than mesiodistal)

  • 2 fossa: Mesial lingual fossa and Distal lingual fossa which is divided by a lingual ridge

  • Has mesial and distal cusp ridges

  • Distal marginal ridge is heavier than the mesial

  • The cusp tip is on a line with the center of the root

  • The cusp tip has a mesial and distal slope, with the mesial being the shorter of the two

  • Mesial contact is at the junction of the middle and incisal thirds (more incisal)

  • Distal contact is at the center of the middle third (more cervical)

  • One root, with mesial and distal developmental grooves. Distal is the deeper of them

  • The cusp tip is a little labial and a little towards the mesial (from incisal view)

  • Longest root in the dental arch

General characteristics of posterior teeth

All posterior maxillary teeth are wider buccolingually than the mandibular posterior teeth

All posterior teeth have broader contact areas

All posterior teeth have less curvature of the cervical line than the anterior teeth

Maxillary 1st Premolars

#’s 5 & 12
Eruption: 10-11 yrs

Root Completion: 12-13 yrs

  • 2 cusps: Buccal and Lingual each are sharply defined Buccal is larger

  • Crown is shorter than the canine

  • Has two roots, buccal and lingual with two pulp canals. When only one root is present, two pulp canals are still present

  • Mesial outline of crown is concave from the cervical line to the mesial contact area (distal outline is straighter)

  • Mesial slope of buccal cusp is straighter and longer than the distal slope (shorter and more curved)

  • Mesial and distal contact are at the same level (occlusal middle thirds) BUT, the distal contact is Broader.

  • Buccal ridge (from strong development of the middle buccal lobe) on the buccal surface

  • Mesial Concavity starts at the cervical of the mesial contact & continues apically beyond the cervical line, joins a Deep Developmental Depression between the roots and ends at the root bifurcation

  • Mesial Marginal Groove is continuous w/ the central groove of the occlusal surface, crossing the mesial marginal ridge immediately lingual to the mesial contact area

  • Distal does not have developmental groove or concavity has abrupt bifurcation

  • Hexagonal shape from occlusal view

  • No supplementary grooves on occlusal surface

  • Well defined central groove

  • Mesial triangular fossa( distal to the mesial marginal ridge)

  • Distal triangular fossa (mesial to the distal marginal ridge)

  • Buccal triangular ridge is more prominent than the lingual triangular ridge (both bases arise from central groove)

  • The MMR, DMR, MBCR, DBCR, MLCR, DLCR enclose the occlusal surface

Maxillary 2nd Premolar

#’s 4 & 13
Eruption: 10-12 yrs

Root Completion: 12-14 yrs

  • Single root with a single pulp canal

  • Root length is as great if not greater than the max. 1st premolar

  • Buccal cusp is smaller than the max. 1st premolar, but still longer than the lingual cusp

  • Cusps are not as sharp as max. 1st premolar (rounder in appearance)

  • Mesial slope of the buccal cusp ridge is shorter than the distal slope (opposite true for max. 1st premolar)

  • No mesial concavity, instead the mesial crown surface is convex

  • No deep developmental groove crossing the MMR

  • From occlusal view the crown is round in shape

  • Multiple supplemental grooves which give the occlusal surface the appearance of being wrinkled

  • Central groove is shorter and irregular

Differences between Maxillary and Mandibular Molars
--Maxillary are wider Buccolingually than Mesiodistally

--Mandibular are wider Mesiodistally than Buccolingually

--Maxillary have 3 roots (Maybe fused)

-Mandibular have 2 roots (Maybe fused)

Maxillary has 4 functional cusps MB, ML, DB, DL with the DL cusp getting proportionately smaller moving posteriorly, so that the DL cusp may even be absent on 3rd molar

--Mandibular have 5 functional cusps on 1st molar, 4 functional cusp on 2nd molar & usually 4 functional cusps on 3rd molars (maybe five)

Maxillary 1st Molars

#’s 3 & 14

Eruption: 6 yrs

Root Completion: 9-10 yrs

  • Largest tooth in maxillary arch

  • 4 well developed functional cusps ML>MB>DB>DL (largest—smallest)

  • 5th nonfunctional cusp named Cusp of Carabelli (located on the mesiolingual cusp)

  • Mesiolingual groove separates Cusp of Carabelli from ML cusp

  • 3 roots mesiobuccal, distobuccal & lingual (palatal)

  • Lingual root is the largest than MB> DB

  • Mesiobuccal cusp is broader than the distobuccal cusp

  • Mesial outline is straighter . Distal outline is convex

  • Mesial contact is pretty occlusal (at junction of middle and occlusal thirds)

  • Distal contact is pretty convex (middle of the middle third)

  • Buccal lingual dimensions are greater than mesiodistal dimensions

  • All three roots can been seen from buccal view

  • The MB root curves distally starting at the middle third

  • Distal root is straighter w/ tendency to curve mesially at middle third

  • Deep developmental groove buccally on the root trunk which starts at the bifurcation and progresses occlusally

  • All molar roots start off as root trunks and than bi/trifrucate

  • Lingual cusps are the only ones to be seen from lingual view

  • ML cusp is always the tallest before occlusal wear

  • Lingual developmental groove starts in the center of the lingual surface mesiodistally & curves sharply towards the distal as it crosses between the cusps ( ML & DL) and than continues on the occlusal surface ending in the distal fossa

  • On mesial surface of crown is a shallow mesial concavity (which is a plaque trap)

  • Distal concavity is near the cervical portion of the crown

  • From occlusal view is rhomboidal in shape

  • Two major fossae: Central fossa-mesial to oblique ridge & Distal fossa- distal to oblique ridge

  • Two minor fossae: Mesial triangular fossa & Distal triangular fossa

  • Oblique Ridge: a type of transverse ridge that is formed by the union of the triangular ridge of the DB cusp and the D ridge of the ML cusp. UNINTERUPTED BY THE CENTRAL GROOVE Do not violate

  • Central pit which is located in the center of the central fossa

  • Buccal groove that radiates from the central developmental pit and continues on the buccal surface between the MB & DB cusps

  • The central developmental groove also begins at the central pit, travels mesially and terminate at the mesial triangular fossa

  • Distal triangular fossa is better developed than the Mesial triangular fossa

  • Distal oblique groove on the occlusal surface in the distal fossa, which connects with the lingual groove at the junction of the cusp ridges of the ML & DL cusps

  • Rhomboidal shape from occlusal view (trapezoidal from buccal view)

Maxillary 2nd Molar

#’s 2 & 15
Eruption: 12-13 yrs

Root Completion: 14-16 yrs

  • Supplement 1st molars in function

  • The roots are as long or longer than 1st molar

  • DB cusp is not as large as the 1st molar. DL cusp is smaller. ML & MB cusps are about same size

  • No cusp of Carabelli

  • Crown is shorter cervico-occlusally and narrower mesiodistally, BUT same size buccolingually (as 1st molar)

  • Buccal roots are the same as 1st molar and are inclined distally compared to 1st molar

  • The roots aren’t spread as far buccolingually—they are getting closer together—even fusing together

  • More of the ML cusp can be seen distally

  • Mesial outline straight—contact being more occlusal

  • Distal outline more convex—contact area being more cervical

  • Rhomboidal shape from occlusal view

  • Have more supplemental grooves as well as pits on occlusal surface

  • No mesiolingual groove because of no cusp of Carabelli

  • No oblique ridge

  • ML & MB cusps are equal in size to the 1st molars but the DL & DB are not are wide

  • Has buccal and lingual grooves—no central groove

Maxillary 3rd Molars

#’s 1 & 16
Eruption: 17-21 yrs

Root Completion: 18-25 yrs

  • Has the most anomalies of all the teeth

  • The roots are usually fused together

  • Poorly developed DL cusp/ may not even be present

  • Heart shaped from occlusal view

  • Normal to have 3 cusps

Mandibular Central Incisors

#’s 24 & 25
Eruption: 6-7 yrs

Root Completion: 9 yrs

  • Smallest teeth in the dental arch in all dimensions EXCEPT for root length which may be as long if not longer than the maxillary central incisor

  • Tooth is symmetrical—illustrates bilateral mesial and distal

  • Mesial AND distal contacts are at the middle of the incisal third (on the same level )

  • Tapers evenly from the contacts areas down to the cervix

  • Mesial incisal angle is SLIGHTLY shaper than the distal incisal angle which is rounder

  • Lingual surface is relatively smooth, slight concavity at the incisal third between the inconspicuous marginal ridges.

  • The MMR, DMR, & LF are present but not marked

  • Root has a mesial and distal developmental depression—distal is more pronounced

  • Larger labiolingually than mesiodistally

Mandibular Lateral Incisors

# 23 & 26
Eruption: 7-8 yrs

Root Completion: 10 yrs

  • Cannot erupt before the mandibular central incisors

  • The mandibular lateral incisor is larger than the mandibular central & the root length is considerably longer than the maxillary centrals

  • Mesial side of crown is longer than the distal causing the incisal ridge to slope in a downward direction DISTALLY

  • Distal contact is more cervical

  • Teeth are twisted on its root base distally. (Looking from incisal edge are twisted distally)

  • Mesioincisal angle is sharper, distoincisal angle is more rounded

  • Mesial and distal cervical curvature line is the same

Mandibular Canines

#’s 22 & 27
Eruption: 9-10 yrs

Root Completion: 12-14 yrs

  • Crown is narrower mesiodistally than the maxillary canine, but the crown is just as long (wider than all mandibular anterior teeth)

  • Labiolingual thickness is less than the maxillary canine

  • The lingual surface is less pronounced than the maxillary canine—less cingulum, MMR & DMR and lingual fossa

  • Mesial contact is near the mesioincisal angle—pretty incisal

  • Distal contact is in the incisal third but more cervical

  • Mesial outline is straighter.

  • Distal outline is rounder

  • Root is shorter than the maxillary canine and apical end is sharply pointed

  • Cusp tip tends to be more lingually inclined than the maxillary canine

  • Has the greatest tendency of all anterior teeth to have bifurcated roots—labial and lingual

Mandibular 1st Premolars

#’s 21 & 28
Eruption: 10-12 yrs

Root Completion: 12-13 yrs

  • Developed from four lobes

  • Mesial, Middle and Distal lobes form one buccal cusp—lingual lobe forms the lingual cusp

  • Large buccal cusp with a small NONFUNCTIONAL lingual cusp

  • Smaller of the mandibular premolars (opposite of the maxillary arch)

  • Lingual cusp resembles a canine while the buccal cusp resembles the 2nd premolar

  • The occlusal surface slopes sharply lingually in a cervical direction

  • Has a Mesiolingual groove which begins in the mesial fossa of the occlusal surface and extends onto the lingual surface

  • Convex buccal surface

  • Lingual less convexity than the buccal

  • Distal contact is broader than the mesial—contacts with 2nd premolar

  • HUGE buccal triangular ridge moves into the lingual triangular ridges and functions as transverse ridge.

  • Diamond shape from occlusal view

  • Buccal triangular ridge is going to come from the middle buccal lobe which makes up a major portion of the occlusal surface

  • Buccal triangular ridge is prominent on the buccal surface

  • Very small lingual triangular ridge

  • Two depression on the occlusal surface: Mesial fossa and Distal fossa (distal the larger of the two)

  • Mesiolingual groove starts from the mesial fossa before extending onto the lingual surface

  • Mesial & distal contacts is near the middle third of the crown—pretty convex

  • Do not violate the buccal triangular ridge

  • The buccal triangular ridge moves into the lingual triangular ridge and functions as a transverse ridge

  • Distal Marginal ridge is higher above the cervix and doesn’t have the extreme lingual sloping of the mesial marginal ridge

  • Lingual view can see most of the occlusal surface, as well as mesial and distal marginal ridges

  • One root which is shorter than the canine and tapers evenly

  • From mesial view—the buccal outline is prominently curved from the cervical line to the tip of the buccal cusp.

  • From distal view—the distal marginal ridge is higher above the cervix and doesn’t have extreme lingual slope (more nearly at right angle)

Mandibular 2nd Premolar

#’s 20 & 29
Eruption: 11-12 yrs

Root Completion: 13-14 yrs

  • Shorter buccal cusp, but everything else is larger compared to mandibular 1st premolar

  • Root is longer and broader than mandibular 1st premolar

  • Apex of the root is blunter

  • May assume two forms

Two-cusp form

Three-cusp form

  • Three-cusp form has 1 buccal cusp and 2 lingual cusps mesiolingual and distolingual

  • Lingual groove, which divides the two lingual cusps

  • ML cusp is larger than the DL cusp

  • Largest cusp B>ML>DL

  • Three-cusp form is angular (square) in shape from occlusal view

  • Two cusp form is round in shape from occlusal view

  • Three-cusp form has well developed triangular ridges separated by deep developmental grooves

  • The mesial developmental groove and the distal developmental groove converge in a CENTRAL PIT and form a “Y” shape on the occlusal surface

  • MDG & DDG travel from the central pit in a distal direction—DDG is the shortest

  • MDG ends in the mesial triangular fossa

  • DDG ends in the distal triangular fossa

  • Two-cusp form has 1 buccal and 1 lingual cusp, w/out a lingual groove

  • Two-cusp form takes on a “U” or “H” shape from occlusal surface (grooves give that shape)

  • Crown & root are wider buccolingually

  • Less of occlusal surface may bee seen from mesial view because of lingual cusp

  • No mesiolingual groove

  • The crown is tapered distally, so when viewing from distal more of the occlusal surface may be seen (THIS IS TRUE OF ALL POSTERIOR TEETH

Mandibular 1st Molars

#’s 19 & 30
Eruption: 6-7 yrs

Root Completion: 9-10 yrs

  • Has 5 functional cusps

  • 3 facial cusps(MB, DB, & D) and 2 lingual cusps(ML & DL)

  • Crown is greater mesiodistally than buccolingually (opposite of maxillary 1st molar)

  • Largest tooth in the mandibular arch

  • Has two roots: Mesial root and Distal root

  • Mesial root is wider and curved distally

  • Distal root is rounder at cervical portion and POINTED in a distal direction

  • Roots are widely separated

  • All 5 cusps are viewed vertically from buccal aspect—the lingual cusps may be see because they are taller than the buccal

  • Mesial buccal groove separates the mesiobuccal cusp and distobuccal cusp & shorter than DBG

  • Distal buccal grooves separates the distobuccal and distal cups

  • MB cusp is the widest mesiodistally of the three facial cusps

  • Part of the distal cusp is on the buccal surface but a major portion of it is on the distal surface

  • Distal contact is on the center of the distal surface of the distal cusp

  • The MB & DB make a major portion of the buccal surface

  • The distal outline of crown is straight

  • The mesial outline is concave—starting from cervical third

  • Mesial contact is more occlusal

  • Mesial root curves mesially to the middle third and than it curves distally to the tapered apex

  • Distal root is less curved but it may slant out towards the distal NOT CURVED DISTALLY and it may show some curvature at its apical either mesially or distally

  • Both roots are wider mesiodistally at the buccal areas than they are lingually

  • The point of bifurcation of the two roots is below the cervical line

  • All roots form from the root trunk of the tooth

  • ML cusp is the widest and tallest

  • When viewed from mesial, only the ML & MB cusps can be see, as well as the mesial root

  • Mesial concavity above the cervical area of the crown right below the contact area

  • From distal view, a great portion of occlusal surface can be seen & some part of each of the 5 cusps can be seen

  • The distal portion of the crown is convex on the distal cusp and the distolingual cusp

  • Distal root is narrower buccolingually than the mesial root

  • From occlusal view is hexagonal in shape

  • One major fossa: Central fossa (well developed)

  • Two minor fossae: Mesial triangular fossa & Distal triangular fossa

  • The developmental grooves on the occlusal surface are:

Central developmental groove

Mesiobuccal developmental groove

Distobuccal developmental groove

Lingual developmental groove

  • The mesial portion of the CDG terminates in the MTF

  • A buccal and lingual supplemental groove join at the mesial portion of the CG called a MESIAL PIT

  • Distal triangular fossa is less distinct than the MTF

  • Distal portion of the CG ends in the DTF

  • Note the difference between the outline form of the mandibular 1st molar and the mandibular 2nd premolar:

The crown of the 1st molar is shorter

The root of the 1st molar is shorter

Molar is wider buccolingually & mesiodistally (for chewing purposes)

The lingual cusp is longer than the buccal on the 1st molar

  • Has two roots—Mesial and distal

Mesial root has two pulp canals( which is normal)

Mesial buccal canal & Mesial lingual canal

Distal root has one canal—distal canal

Mandibular 2nd Molar

#’s 18 & 31
Eruption: 11-13 yrs

Root Completion: 14-15 yrs

  • The crown has four well-developed cusps—2 buccally & 2 lingually

  • MB is wider than the DB cusp

  • Two roots—mesial and distal, not as broad as the mandibular 1st molar buccolingually, nor are they so widely spread apart

  • A buccal groove which separates the MBC & DBC

  • A lingual groove which separates the MLC & DLC

  • No distal cusp and no distal buccal groove

  • Not as prominent cervical bulge on the buccal as seen on the mandibular 1st molar

  • Many more supplemental grooves

  • Rectangular shape from occlusal view

  • Four main grooves on the occlusal surface arranged in a “+ 4” configuration

  • The buccal and lingual grooves meet the central groove at right angles at the central pit and form a cross shape dividing the occlusal surface into four nearly equal parts

Mandibular 3rd Molars

#’s 17 & 32
Eruption: 17-21 yrs

Root Completion: 18-25 yrs

  • Can 4—5 cusps (can also find some with more than 5 cusps)

  • Most mandibular 3rd molars are not normal in size. They are larger than normal in the crown portion ( the opposite is true of the maxillary 3rd molars—most of there anomalies are undersized)

  • Four cusp type is more likely to be in better alignment and good occlusion than the 5 cusp form

  • Two roots—mesial and distal

  • The roots are shorter and poorly developed.

  • The roots may be separated with a definite point of bifurcation or they may be fused for all or part of there length

  • From the occlusal has a rounded outline with smaller buccal lingual measurement

The Deciduous Dentition


Deciduous Teeth (A-T) Mean Eruption Root Completion

(Months) (Years)

Maxillary Central Incisors 10 mos. 8-12 mos. 1½ yrs


Maxillary Lateral Incisors 11 mos. 9-13 mos. 2 yrs


Maxillary Canines 19 mos. 16-22 mos. 3 yrs


Maxillary 1st Molars 16 mos. 13-19 mos. (M) 2 yrs

(B&I) 14-18 mos. (F)

Maxillary 2nd Molars 29 mos. 25-33 mos. 3 yrs


Mandibular Central Incisors 8 mos. 6-10 mos. 1 yrs


Mandibular Lateral Incisors 13 mos. 10-16 mos. 1 yrs


Mandibular Canines 20 mos. 17-23 mos. 3 yrs


Mandibular 1st Molars 16 mos. 14-18 mos. 2 yrs


Mandibular 2nd Molars 27 mos. 23-31 mos. (M) 3 yrs

(K&T) 34-30 mos. (F)
Major Contrasts of Deciduous Teeth and their Permanent Counterparts

  1. The crowns of the deciduous teeth are wider mesiodistally in comparison to their crown length of the permanent teeth. (The primary teeth look stubby as compared to the permanent teeth)

  1. The roots of the deciduous anterior teeth are narrower and longer

  1. The roots of the deciduous molars are longer, more slender, and flare more. The roots flare beyond the outline of the crown allowing for the development of the premolar crowns. The long roots guide the erupting premolar into place.

  1. The cervical ridges on the primary anterior and posterior teeth are much more prominent than on the permanent teeth. The cervical ridges on the anterior are quite prominent labially and lingually. The cervical ridges on the posterior teeth are more prominent buccally, especially on the maxillary and mandibular 1st molars.

  1. The crowns and roots of deciduous molars at the cervical portion are more slender mesiodistally than those of the permanent molars. (pencil necks)

  1. The buccal and lingual surfaces of deciduous molars have a narrower occlusal surface than the permanent molars.

  1. The deciduous teeth are less pigmented and lighter in color than the permanent teeth.

8. The deciduous teeth have a smaller root trunk compared to the permanent teeth

Pulp Chambers and Pulp Canals in Deciduous Teeth

  1. The enamel is relatively thin and has a consistent depth.

  1. The dentin thickness between the pulp chambers and the enamel is limited, particularly in some areas.

  1. The pulpal horns are high and the pulp chambers are large.

  1. The deciduous roots are narrow and long when compared with crown width and length.

  1. Molar roots of deciduous teeth flare markedly, and thin out rapidly as the apices are approached.

Comparison of Posterior Deciduous Teeth to Posterior Permanent Teeth

  • The deciduous maxillary 1st molar resembles a permanent premolar.

  • The deciduous maxillary 2nd molar resembles a permanent maxillary 1st molar: THEREFORE a Cusp of Carabelli is present as well as an oblique ridge

  • The deciduous mandibular 1st molar DOES NOT resemble any of the other teeth in the mouth (deciduous or permanent)

  • The deciduous mandibular 2nd molar resembles the permanent mandibular 1st molar: THEREFORE five functional cusps are present

Usual Order of Appearance

  1. Central Incisors

  2. Lateral Incisors

  3. First Molars

  4. Canines

  5. Second Molars

Usual Order of Appearance of Permanent Teeth

  1. First Molars

Maxillary 6 yrs

Mandibular 6-7 yrs

  1. Mandibular Central Incisors

6-7 yrs

  1. Mandibular Lateral Incisors

7-8 yrs

  1. Maxillary Central Incisors

7-8 yrs

  1. Maxillary Lateral Incisors

8-9 yrs

  1. Mandibular Canines

9-10 yrs

  1. Maxillary 1st Premolars

10-11 yrs

  1. Maxillary 2nd Premolars

10-12 yrs

  1. Mandibular 1st Premolars

10-12 yrs

  1. Mandibular 2nd Premolars

11-12 yrs

  1. Maxillary Canines

11-12 yrs

  1. Mandibular 2nd Molars

11-13 yrs

  1. Maxillary 2nd Molars

12-13 yrs

  1. Third Molars

17-21 yrs

**** For root completion, generally add two after the last eruption year for anterior teeth and for posterior teeth add three years after last eruption date.

The mandibular will usually precede the maxillary on the first molars

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