Intro to Dental Terminology // Lecture 1 Flashcards
Homodonts
Animals that have teeth all within the same dentition
Heterodonts
Animals W/ teeth that have different classes
Monophyodont
“Having one set of teeth” (ex beluga whale, deli, porpoise)
Polyphydont
Dentitions w/an endless succession of teeth
(Ex: shark, frog )
Diphyodont
“Having 2 sets of teeth “
Mammals usually have primary (deciduous) and secondary (permanent) dentitions
Humans are :
Diphyodonts and heterodonts
Maxillary arch
Upper jaw
Mandibular arch
Lower jaw
Primary dentition
- ages 2-6
-3 classes: incisors, canines, molars
-20 teeth
-all teeth lost by 12/13
Formula for primary dentition
I 2/2 C 1/1 M2/2 = 5 upper teeth & 5 lower teeth in each quadrant
Secondary dentition
-adults
-32 teeth
- four classes ; incisors, canines, premolars, molars
Formula for secondary teeth
I 2/2 C 1/1 PM 2/2 M 3/3 = 8 teeth per quadrant
Anterior teeth
Incisors and canines
Posterior teeth
Premolars and molars
Universal tooth identification system
Lettered A-T starting at max. right 2nd molar (primary)
Numbered 1-32 starting at max. right 3rd molar (secondary)
FDI FIRST DIGIT
Two digits for each tooth
- first digit = quadrant
1=perm dent, max right quad
2= perm dent, max left quad
3=perm dent, mand left quad
4= perm dent, mand right quad
5= prim dent, max right quad
6= prim dent, max left quad
7=prim dent, mand left quad
8= prim dent, mand right quad
FDI second digit
Tooth position relative to midline
1= central incisor, 8= 3rd molar
Palmer notation system
Ortho & oral surgeons
Four bracket shapes
] = upper right quad
[ = upper left quad
-] = lower right quad
[- = lower left quad
(Letter or number would be in space)
Tooth anatomy overview
Enamel, dentin, cementum are relatively hard (calcified)
Only enamel and cementum normally visible in intact extracted tooth
Enamel
White, protective external surface layer of anatomic crown
Hardest substance in body
95% calcium hydroxyapatite, 5% water & enamel matrix
Develops from ectoderm (enamel organ) and product of epithelial cells called ameloblasts
Cementum
Dull yellow external layer of tooth root
Very thin
65% calcium hydroxyapatite (mineralized and calcified), 35% organic matter (collagen fibers)
Softer than enamel, about as hard as bone
Develops form the dental sac (mesodermal), produced by cementoblasts
Dentin
Hard yellowish tissue underlying enamel and cementum
Major bulk of inner Postino of each tooth crown & root
Visible in radiograph or when tooth has been worn due to decay or restoration process
Harder than cementum, softer & less brittle than enamel
70% calcium hydroxyapatite, 18% organic matter and water
Develops from embryonic dental papilla (mesodermal) and formed by odontoblasts
Pulp
Soft connective tissue in the cavity of the tooth crown& root (pulp cavity) - lots of blood vessels and nerves
Coronal portion = pulp chamber
Root portion = pulp canal or root canal
Surrounded by dentin expect a hole(s) near apex = apical foramen where nerves and blood vessels enter
Develops from dental papilla (mesoderm)
Periodontal ligament
Dark line surrounding tooth between enamel and alveolar bone