Deciduous Teeth Flashcards
Which primary molars could be mistaken from permanent molars?
Primary maxillary and mandibular 2nd molars
Which primary molar could be mistaken for a premolar?
Maxillary 1st molar
Which primary molar looks like no other tooth, either deciduous or permanent?
Mandibular 1st molar
How are the primary molar roots different from a permanent molar?
a. How are they similar?
Flared much more
a. Same number of roots
From a proximal view, how does the angulation of the primary anterior root differ from the permanent anteriors?
Flared facially (labially)
How many Mamelons does a primary anterior incisor have?
None
Which primary anterior tooth is most likely to exhibit a lingual pit?
Maxillary central
How does the crown:root of a primary tooth compare with a permanent’s?
Primary crown smaller and root longer (in comparison)
In a normal 10-year old child, how many primary and permanent teeth would you expect to find?
Primary 10, Permanent 14
How do the primary maxillary central and lateral incisors compare with the permanent incisors?
Flatter, more round, plump
What is unique about the relative lengths of the MD to IC dimensions of the primary maxillary central incisor?
MD > IC
What incisal feature is missing from primary incisors but is seen unworn incisal edges of permanent incisors?
Mamelons
A unique feature of the primary maxillary canine is the relative lengths of the mesial and distal cusp ridges. Which is longer, which is shorter?
a. How is this unique?
Mesial cusp ridge > distal cusp ridge
a. Mesial is longer than distal to start
A unique feature of the primary maxillary and mandibular canines is the location of their mesial and distal HOC’s. What is unique about their relative position?
They are equal
a. Mesial might be more cervical
Which two cusps are prominent and which two are diminished in a primary maxillary 1st molar?
a. Which of the four cusps might not be evident at all?
ML (Largest) MB (next largest)
a. DL
What is unique about the curvature of the facial cervical line of a primary maxillary 1st molar?
Depth of curvature towards mesial
From an occlusal view of the primary maxillary 1st molar, it presents a figure that has how many sides?
a. Which permanent teeth would this most closely resemble?
5 sided
a. 3 cusp premolar
How does the relative size of a primary maxillary 1st and 2nd molar compare with each other?
a. How is this different from that of a permanent maxillary 1st and 2nd molar?
2nd larger than the first
a. Opposite (1st is larger than the 2nd)
Which permanent or primary tooth does the primary mandibular 1st molar resemble?
a. What are the features that identify it as a mandibular molar?
None
a. 4 cusps, 2 roots
There is a definitive offset of the facial cervical line of a primary mandibular 1st molar. Where is this offset located?
Mesial
How is the number of cusps of a primary mandibular 1st molar differ from that of a permanent mandibular 1st molar?
4 cusps on primary (5 cusps of permanent)
Which occlusal pit is most often missing in a primary mandibular 1st molar?
Distal pit
Which tooth does the primary mandibular 2nd molar most closely resemble?
Permanent 1st mandibular molar
What is dental lamina derived from?
Oral Epithelium
What happens during the bud stage of formation?
Epithelial thickening (dental lamina) – 6-8 weeks fetal development
a. Differentiated into tooth buds
b. Buds: round or ovoid
What appearance occurs during the cap stage?
Cap Stage
a. Enamel organ →ameloblast
b. Dental papillae → odontoblast
c. Dental follicle → cementoblast, osteoblast, fibroblast
What happens during the bell stage of development?
Concavity deepens
a. DEJ identifiable
b. Permanent tooth bud begins formation
What begins the formation of the root development?
Hertwig’s Root Sheath
a. Bell stage = formation of CE Line
What happens at root completion?
One year from eruption to completion
a. Apical foramen become constricted
What are the two types of Eruption?
Eruption
a. Active → entry of tooth till it touches other teeth
b. Passive → continuous adaptation (throughout life)
Pattern of Deciduous Eruption Pattern?
Central Incisors → Lateral incisors → First Molar → Canines → Second Molar
a. Mandibular before maxillary
What is the Mixed Dentition Period?
6-12 years (form “primate” spaces)
Where do the permanent teeth develop in relations to primary teeth?
Development
a. Anteriors → permanent are lingual to primary
b. Premolars → within the flared roots
Resorption is what kind of a process?
Osteoclastic Processes
a. One year prior to exfoliation
What is Ankylosis?
Root fused to bone, disrupts resorption and exfoliation
What is the Dental formula for primary dentition?
I 2/2 C 1/1 M 2/2
a. Important to maintain arch spacing for permanent dentition
