14. Signing of teeth, morphology of the teeth. Guide planes and cephalometric landmarks. Flashcards
I. Signing of the teeth
1. What are the 3 methods for signing?
- Zsigmondy cross
- FDI (Federation Dentaire Internationale) Signing system
- ADA (American Dental Association) numbering
I. Signing of the teeth
2. Characteristics of FDI (Federation Dentaire Internationale) Signing system
- FDI tooth numbering formula (adapted by WHO) for permanent teeth is referred to by a two-
digit number, the first one for the quadrant and the second for the tooth order from mesial to distal.
I. Signing of the teeth
3. Characteristics of ADA (American Dental Association) numbering
‣ The teeth are marked with consecutive numbers following a clockwise order begnning with the maxillary right third molar (1) and continuing to the mandibular right third molar (32)
‣ Individual teeth or tooth groups are often given an acronym:
* “I” stands for incisors
* “C” for canine
* “PM” for premolar
* “M” for molar.
I. Signing of the teeth
4. Characteristics of Zsigmondy (1861) system
A. The first digit denotes the quadrant (right and left) and arch (maxillary or mandibular and dentition (permanent or primary)
B. The second digit denotes the tooth position in each quadrant relative to the midline
I. Signing of the teeth
4B. How to use Zsigmondy (1861) system in case pf permanent and primary teeth?
I. Signing of the teeth.
5. How many teeth does a person have?
Adult: 32 teeth
Children: 20 teeth (no premolars)
II. Morphology of the teeth
1. List the tooth surfaces
1/ Vestibular or facial
‣ Surface, looking at the oral vestibulum
2/ Labial:
‣ Surface, contacting the lips
3/ Buccal:
‣ Surface contacting the cheeks
4/ Oral:
‣ Surface, looking at the oral cavity
5/ Lingual:
‣ On the mandible
6/ Palatal:
‣ On the maxilla
7/ Proximal
‣ Tooth surfaces contacting with eachother:
8/ Mesial
‣ Surface looking at the midline
9/ Distal
‣ Surface looking at far from the midline
10/ Occlusal
‣ Occluding surfaces
II. Morphology of the teeth
2A. What are the 3 parts of a tooth?
Dental crown – Corona dentis: (1)
Radix dentis (2)
Cervix dentis (3)
II. Morphology of the teeth
2A. What are the 3 parts of a tooth?
Dental crown – Corona dentis: (1)
Radix dentis (2)
Cervix dentis (3)
II. Morphology of the teeth
2B. Characteristics of Dental crown – Corona dentis: (1)?
‣ intraorally located, polychromatic, covered with enamel, anatomically finished at the cemento-enamel junction,
‣ the free gingival margin is attached a little bit more occlusally
‣ clinical crown: coronal part of the tooth that is visible in the mouth (not always is the same as the anatomical crown)
II. Morphology of the teeth
2C. Characteristics of Radix dentis (2)
‣ situated in the alveolar process, covered with cementum
‣ its shape is dependent on the type of the tooth
II. Morphology of the teeth
2D. Characteristics of Cervix dentis (3)
‣ line formed by cemento-enamel junction, the border between the crown and the root
‣ its shape is uneven, its shade is more yellowish
III. Guide planes and cephalometric landmarks
1. What are the 6 important cephalometric landmarks?
- TA: terminal hinge axis
- O: Orbitale
- P: Pogonion
- N: nasion
- Sn: Subnasale
- Gn: gnathion
III. Guide planes
2A. What are the 4 Cephalometric reference planes?
- Sella – Nasion plane (I.)
- Frankfort plane (II.)
- Camper’s plane (III.)
- Occlusal plane (IV.)
III. Guide planes
2B. What are the characteristics of Frankfort plane (II.)?
It is the plane between the left and right porion (Po), and the left orbitale (Or) points, parallel with the horizontal plane, when the head is in upright position.
III. Guide planes
2C. What are the characteristics of Camper’s plane (III.)?
It is the plane between the tragion (porion) of both sides and the subnasale point, parallel with the occlusal plane
III. Guide planes
2D. What are the characteristics of Occlusal plane (IV.)?
It is the plane between the mesial angle of the left mandibular first incisor (incision inferius point) and distobuccal cusp tips of the last mandibular molars
