Dental Anatomy - Permanent
Mn 2nd M (18,31)
- MOST symmetrical molar - MOST common tooth to have cervical enamel projections - B-L dimension is greater at the mesial than distal - Cusps are same height when viewed from buccal - Occlusal is rectangular - Proximal is Rhomboidal - 4 cusps (MB largest, DB, ML, DL) - Occlusal pattern resembles "+" - Occludes with Mx 1st and 2nd M
Mx Laterals (7,10)
- 3rd most morphologically variable (peg lateral, dens-in-dente) - 3rd most congenitally missing (next to 3rd M) - MOST common tooth to have a Palato-Radicular groove - Occlusal - Ovoid - Proximal - Trangular - MOST developed lingual anatomy of all anterior teeth - Lingual surface is the MOST concave of all incisors - Cingulum - central, often location of talon cusp, causing a lingual pit - Root just as long as central, typically curves distally. - Occludes with Mn lateral and canine
Mx 2nd PM (4,13)
- Has buccal cusp ridge, not as prom as 1st PM - Occlusal - hexagonal - Proximal - Trapezoidal - occlusal table is more ovoid - Buccal cusp height = Palatal - ONLY PM without a mesial root depression - Occludes with Mn 2nd and 1st M
Mn 1st M (19,30)
- LARGEST Mn tooth - WIDEST tooth (M-D) - FIRST perm tooth to erupt - MOST restored/extracted tooth - See all 5 cusps from buccal - B cusps are shorter and blunter than L - Occlusal shape is Pentagonal - Proximal is Rhomboidal (tilted lingually) - 5 cusps (MB largest, DB, Distal smallest, ML tallest, DL) - Two transverse ridges, Two buccal grooves (MB, DB) - Roots (2) wide and separated - Mesial root is longer and wider (B-L) - Both roots have concavities - Occludes with Mx 2nd PM and 1st M
Mx 1st PM (5,12)
- LARGEST of all premolars - Prominent buccal ridge - Only perm tooth mesial cusp ridge > DCR -Two Roots (B > P) -Mesial Marginal Developmental Groove -Mesial concavity - Occlusal - Hexagonal - Proximal - trapezoidal - Sits most vertically in alveolar bone - Occludes with Mn 1st & 2nd PM
Mx 1st M (3,14)
- LARGEST perm tooth - ONLY tooth that is broader lingually then buccally - Widest tooth (B-L) - 1st Perm tooth to erupt - ONLY tooth with pronounced DISTAL concavity at CEJ - Long buccal groove with pit - Distolingual groove with pit (on all Mx molars) - Occlusal - Rhomboidal - Proximal - Trapezoidal - 4 cusps (ML>MB>DB>DL) - 5th Cusp sometimes, Cusp of Carabelli (tubercle) - Primary Trigon (MB - DB - ML) - Secondary cusp triangle - Formed by DL cusp - ONLY tooth with two triangular ridges on one cusp (ML) - MOST prominent oblique ridge of Mx Molars - Transverse groove of oblique ridge connects the central and distal fossa (same for all Mx molars) - 3 roots, MB, DB (shortest) and Palatal (longest - most prone to perf mx sinus) - MB and DB are shaped like plier handles - Occludes with Mn 1st and 2nd M
Mn Canines (22,27)
- LONGEST crown - Second longest tooth (Mx Canine), longest tooth in Mn - Second longest root (Mx Canine) - Mn tooth least likely to be extracted - Has facial ridge - Mesial cusp ridge < distal - Mesial surface nearly parallel to long axis - Anterior tooth MOST likely to have a bifurcated root - ONLY root that may be mesially inclined - Occludes with Mx lateral and canine
Mx Canines (6,11)
- LONGEST tooth in mouth (longest root) - LONGEST Cusp - Third longest crown (next to Mn canine & Mx Central) - WIDEST B-L anterior tooth - Mx least likely to be extracted - Prominent lingual & facial ridge - Cusp tip centered over root - Mesial cusp ridge < distal - Mesial surface is straighter (less convex) than distal - Root is oval-shaped and flattened M-D (deeper on distal) - Occludes with Mn canine and 1st PM
Mn 3rd M (17,32)
- MOST variable morphology (with Mx 3rd M) - MOST common congenitally missing tooth - MOST freq impacted tooth - MOST common tooth to have enamel pearls - Bulbous crown that tapers distally - Proximal is Rhomboidal (tilted lingually) - Roots usually short, distally inclined and often fused - Typically has distally inclined root trunk and apices - Occludes with Mx 2nd and 3rd M
Mx 3rd M (1,16)
- MOST variable shape of any other tooth - Second most congenitally missing (Mn 3rd Molar) - SHORTEST perm tooth - MOST common to have enamel pearls - SHORTEST Mx Crown - Occlusal - Heart shaped (DL cusp absent) - Proximal - Trapezoidal - Crown tapers lingually - 3 Cusps (MB, DB, lingual) - Roots often fused and distal - Occludes ONLY Mn 3rd M
Mn 2nd PM (20,29)
- Most congenitally missing PM - Gingival papilla between 1st and 2nd PM is SHORTEST - Occlusal shape is square - Proximal shape is Rhomboidal - Occlusal surface can have THREE configurations (2, 2, or 3 cusps) - 2 cusps - "H"; 2 cusps - "U"; 3 cusps - "Y" (most common) - ML >DL cusps - B is shorter and blunter than ML - Mesial marginal ridge has slight concavity - Apex is CLOSEST to Mental Foramen (can cause unneeded RCT) - Occludes Mx 1st & 2nd PM
Mn 1st PM (21,28)
- SMALLEST of all premolars - PROMINENT mesio-lingual groove - MMR <DMR - Occlusal is diamond shaped - Proximal is Rhomboidal - ONLY posterior tooth with a lingual tipped occlusal plane - MOST prominent transverse ridge of all PM - 2 cusps (B >>> L) - Occludes Mx Canine and 1st PM
Mn Central (24,25)
- SMALLEST tooth - Bi-Symmetrical (only tooth) - NARROWEST (m-d) tooth - GREATEST mesial CEJ of Mn teeth - FIRST succedaneous tooth to erupt - MMR = DMR - Cingulum - central and indistinct - Root has mesial and distal concavities (hour glass shape) - Longer than Mx central - Occludes with Mx central ONLY (only anterior tooth to occlude with one tooth)
Mx 2nd M (2,15)
- Similar to Mx 1st M, but smaller and more angular - Second most common tooth to have enamel projections (next to Mn 2nd M) - CLOSEST tooth to Stenson's duct (parotid) - Short buccal groove, no pit - Occlusal table - Rhomboidal/Heart if DL is absent - Proximal is trapezoidal - 4 cusps (ML>MB>DB>DL) - Roots are typically longer, closer together, more distally inclined than 1st M - Occludes Mn 2nd & 3rd M
Mn Laterals (23,26)
- Slightly larger than Mn central - Second smallest tooth (Mn central) - Not as symmetrical as Mn central - Crown is tilted distally - MMR > DMR - Incisal edge is twisted DL - Cingulum - slightly distal and indistinct - LONGEST root of all incisors - Root has mesial and distal concavities, hour glass shaped - Occludes Mx central and laterals
Mx Centrals (8,9)
- WIDEST M-D of all anterior teeth - MOST prominent tooth - GREATEST mesial CEJ contour of all teeth - Second longest crown next to Mn Canine - Occlusal - Triangular - Proximal - Triangular - 3 Mamelons & 4 developmental grooves - M-D > F-L from occlusal - Least likely to have divided root canal - Has GREATEST axial inclination toward facial -Occludes with Mn central & lateral incisors
Eruption sequence Mn arch
M1 - 6yrs I1 - 6-7yrs I2 - 7-8yrs C - 9-10yrs PM1 - 10-12yrs PM2 - 11-12yrs M2 - 12yrs M3 - 17-21yrs Perm Mn teeth typically erupt before Mx teeth, except for the PM's
Eruption sequence Mx arch
M1 - 6yrs I1 - 7-8yrs I2 - 8-9yrs PM1 - 10-11yrs PM2 - 10-12yrs C - 11-12yrs M2 - 12 yrs M3 - 17-21yrs
LAST Succedaneous tooth to erupt?
Mx CANINE!
Calcification
know that it is complete (except for 3rd molars) by age 8. This is important for tetracycline usage. Apices are complete about 2.5 years after eruption