Deciduous & Pulp

• Pulp:

  
  

  what are the primary molars pulp canals like?

  - Same number of pulp horns as there are cusps on crown.

  
  

  Maxillary- 3 roots, 4 canals (each root has one canal and one root has 2 canals)

  Mandibular- 2 roots, 4 canals (each root has 2 canals)
• Pulp:

  
  

  what are the primary canines pulp canals like?

  - single canal

  - oval cross section
• Pulp:

  
  

  what are the primary incisors pulp canals like?

  - Typically single canal

  - oval cross section

  - many accessory canals
• Pulp:

  
  

  What are some general features of the pulp cavities of deciduous teeth?

  - Smaller depth of dentine between the pulp chamber and the enamel, especially in the mandibular second deciduous molar.

  - Very thin, highly projecting pulp horns in the molars, especially mesial.

  - The pulp chamber is relatively larger than in the corresponding permanent tooth as a result of the thinner

  dentine walls which enclose it.

  - There are no clearly defined root canal entrances.

  - Long root canals; in the molars the root canals are often irregular and ribbon like.

  - The root canals of the deciduous molars diverge greatly.

  - Thin enamel
• Pulp:

  
  

  what is the difference between primary and secondary tooth pulps?

  primary pulps have larger chambers and more pronounced pulp horns
• Pulp:

  
  

  Where are accessory root canals found?

  In the apical part of the roots & all the teeth, and around the surfaces of the root apex as accessory apical foramens

  
• Pulp:

  
  

  What are accessory root canals?

  Accessory root canals are smaller canals alongside the main root canals, which connect the pulp to the periodontium through other routes than the main canal.

  
• Pulp:

  
  

  What is found at the root apex?

  A small opening called the apical foramen

  
• Pulp:

  
  

  Where does the root canal extend from and to?

  It extends from the pulp chamber to the root until it reaches the root apex where it terminates

  
• Pulp:

  
  

  What are the 2 main parts of the dental pulp?

  Pulp chamber & root canal

  
• Pulp:

  
  

  what is a pulp?

  Tooth pulp is the innermost layer of your tooth. It contains nerves, blood vessels, specialized cells and connective tissues, which provide nutrients for your tooth.

  
• what is the chronology of the primary mandibular second molar ?

  initial calcification: 6 months in utero.

  Completion of crown: 10 - 12 months.

  Eruption: 1 ¾ - 2 ½ months.

  Completion of root: 3 years
• Describe the primary mandibular second molar


  - Same arrangement of cusps and roots as the mandibular first

  permanent molar

  - Smaller and whiter than lower first permanent molar but larger than the mandibular first deciduous molar

  -Prominent cervical bulge on buccal surface of crown. Buccal surface inclined lingually

  - Occlusal outline rectangular.

  - Buccal cusps approximately equal in size.

  - Two widely divergent roots; mesial root longer and flattened

  mesiodistally

  
  

  -> partial diversion of the mesial root may sometimes be present

  
• what is the chronology of the primary maxillary second molar ?

  initial calcification: 6 months in utero.

  Completion of crown: 10 - 12 months.

  Eruption: 1 ¾ - 2 ½ years.

  Completion of root: 3 years
• Describe the primary maxillary second molar

  - Morphology of maxillary first permanent molar duplicated on a smaller scale

  - More prominent bulge on cervical part of buccal surface.

  - Three roots.

  - Roots have wider divergence than those of the maxillary first

  permanent molar

  - Cusp of Carabelli present in most cases

  
  

  -> Cusp of Carabelli may be absent.

  -> Very rarely the distopalatal cusp may be so reduced as to be scarcely discernible.

  -> Buccal roots may be partially fused

  
• what is the chronology of the primary mandibular first molar ?

  initial calcification: 5 months in utero.

  Completion of crown: 6 months.

  Eruption: 12 - 16 months.

  Completion of root: 2 - 2 ½ years.
• Describe the primary mandibular first molar

  - Molar tubercle of Zuckerkandl an exaggerated cervical bulge on the buccal surface of the crown over the mesial root, with a considerable cervical constriction.

  - Four cusps: buccal cusps compressed labiolingually with no clear separation between them in contrast to the two lingual cusps which are clearly defined and roughly conical in shape.

  - Mesiobuccal cusp is the largest.

  - Tooth longer mediodistally than labiolingually.

  - Mesial marginal ridge more pronounced than distal.

  - Two roots flattened mesiodistally.

  The mesial is the longer and from the mesial aspect appears rectangular, and is often grooved.

  
  

  -> Distolingual cusp is sometimes very insignificant.

  -> Buccolingual crest occasionally absent

  
• what is the chronology of the primary maxillary first molar ?

  initial calcification: 5 months in utero.

  Completion of crown: 6 months.

  Eruption: 12 - 16 months.

  Completion of root: 2 - 2 ½ years.
• Describe the primary maxillary first molar

  - Pronounced bulge on mesial side of buccal surface: molar

  tubercle of Zuckerkandl.

  - Trapezoid coronal outline with narrow occlusal surface running mesiodistally.

  - Palatal surface shorter, mediodistally, than the buccal surface.

  - Mesiopalatal cusp largest and most pointed.

  - Widest labiopalatal crown measurement at mesial end.

  - Three widely divergent roots

  
• what is the chronology of the primary mandibular canines?

  initial calcification: 5 months in utero.

  Completion of crown: 9 months.

  Eruption: 16 - 20 months.

  Completion of root: 2 ½ - 3 years
• Describe the primary mandibular canines

  - Smaller and slimmer overall than the maxillary deciduous canine.

  - Distal slope longer than mesial.

  - Concave lingual surface.

  - Less well-defined labial and lingual longitudinal ridges; lingual ridge often completely absent.

  - Single tapering root inclines distally and slightly labially

  
• what is the chronology of the primary maxillary canines?

  Initial calcification: 5 months in utero.

  Completion of crown: 9 months.

  Eruption: 16 - 20 months.

  Completion of root: 3 years
• Describe the primary maxillary canines

  - Mesial slope of longer than distal slope.

  - Conical crown with pronounced cervical bulge and pointed cusp.

  - Crown smaller and more bulbous than that of the upper permanent canine.

  - Labial and palatal longitudinal ridges extending from cusp tip

  - The incisal aspect displays a diamond-shaped outline with rounded corners from an incisal aspect.

  - Cervical margin extends further incisally on the mesial surface than on the distal surface.

  - Slender tapering single root often more than twice the length of the crown with a tendency to incline distally. Cross-section similar to that of the maxillary permanent canine, triangular.

  
  

  -> Asymmetrical and symmetrical crown forms are equally common.

  -> An occasional variation is the flattening or partial bifurcation of the labial surface of the root, resulting in a longitudinal labial groove and a heart-shaped cross-section of the root.

  
• what is the chronology of the primary mandibular Lateral Incisors?

  Initial calcification: 4 ½ months in utero.

  Completion of crown: 4 ½ months.

  Eruption: 7 months.

  Completion of root: 1 ½ - 2 years
• Describe the primary mandibular Lateral Incisors

  - Rounded disto-incisal angle; sharp mesio-incisal angle.

  - Single tapered root with round cross-section, tends to incline distally.

  - Incisive edge slopes downwards from medial to slightly lower distal surface in unworn specimens.

  - Crown may show twisting on root in order to allow the incisive edge to follow the mandibular arch.

  - Larger than mandibular first deciduous incisor.

  - Lingual surface may be more concave than that of the mandibular deciduous central incisor.

  - Single root which is generally longer than that of the mandibular first deciduous incisor.

  
• what is the chronology of the primary maxillary Lateral Incisors?

  Initial calcification: 4 ½ months in utero.

  Completion of crown: 5 months.

  Eruption: 8 - 9 months.

  Completion of root: 1 ½ - 2 year
• Describe the primary maxillary Lateral Incisors


  - Similar shape to Mx first deciduous incisor but crown smaller

  and narrower in proportion.

  - Palatal cingulum is less pronounced.

  - Cervical margin most curved on mesial side.

  - Rounded disto-incisal angle; sharp mesio-incisal angle.

  - Single root.

  
  

  -> Rare in contrast with highly variable Mx 2nd permanent incisor

  
  

  charting: 52 and B_|

  
• what is the chronology of the primary mandibular central incisors?

  Initial calcification: 4 ½ months in utero.

  Completion of crown: 4 months.

  Eruption: 6 ½ months.

  Completion of root: 1 ½ - 2 years.
• Describe the primary mandibular central incisors

  - Single tapered root more rounded than that of mandibular

  first permanent incisor. Tends to incline distally.

  - Smallest tooth in the deciduous dention.

  - Cervical margin most curved on mesial side.

  - Bulge on labial surface at cemento-enamel junction.

  - Chisel-shaped crown.

  
  

  -> The pronounced cervical bulge on the labial surface may be reduced or completely absent

  
• what is the chronology of the primary maxillary central incisors?

  Initial calcification: 3-4 months in utero.

  Completion of crown: 4 months.

  Eruption: 7 ½ months.

  Completion of root: 1 ½ years.
• Describe the primary maxillary central incisors

  - Rounded disto-incisal angle and sharp mesio-incisal

  angle.

  - Crown similar to upper first permanent incisor but

  smaller and plumper overall.

  - Large palatal cingulum and pronounced bulge on

  labial surface.

  - Root tilts distally and slightly labially from long axis of

  crown, and tapers to a blunt apex.

  - The mesiodistal and cervico-incisal dimensions of the

  crown are nearly the same

  
• Compare and contrast primary & secondary incisors.

  - Crown and root form of a primary incisor is similar but the primary is on a smaller scale

  - In a primary incisor, the crown mesiodistal width and the cervico-incisal length are approximately equidistant

  - In a secondary incisor the crown mesiodistal width < the cervico-incisal length

  -The primary incisor has a rounder, fuller, shovel shaped crown

  
• How do primary teeth differ from secondary teeth?

  Primary teeth:

  - Are smaller

  - Enamel is whiter, more opaque, more permeable/prone to wear

  - Depth of enamel more consistent & thinner

  - More pronounced cervical margin with bulging enamel

  - Coronally bulbous (crowns)

  -Roots are shorter, weaker & lighter coloured

  - Have relatively larger pulp chambers than secondary teeth with prominent pulp horns

  - Have fine root canals

  - Have a more constant tooth morphology than secondary teeth with fewer variations
• what are the abbreviations for describing teeth?

  • Primary - 1°

  • Secondary - 2°

  • Maxillary - Mx

  • Mandibular - Md

  • Vestibular - V

  • Palatal - P

  • Lingual - L

  • Mesial - M

  • Distal - D

  • Incisal - I

  • Occlusal - O
• What are the eruption dates for primary and permanent dentition?

  -> for primary teeth, the root of the tooth is completed one year after eruption

  
• How do you use the Zsigmondy/Palmer notation to name deciduous teeth?

  - Central incisors=A up until second molar=E

  - The quadrants are identified by drawing it out e.g. upper left quadrant = L
• How do you use the FDI system to name deciduous teeth?

  - Upper right quadrant is given the prefix 5, upper left=6, lower left=7, lower right=8.

  -The teeth are named from the central incisor so central incisor=1 up to second molar=5
• what are deciduous teeth?

  primary/baby/milk teeth:

  - 4 incisors

  - 2 canines

  - no premolars

  - 4 molars

  -> in each jaw so in total: (4+2+4)x2= 10x2= 20 teeth