Chapter 15 Notes: Tooth Numbering Systems, Dentition Periods, and Key Terminology
Part Two: Numbering Systems
Three numbering systems discussed for identifying teeth:
Universal numbering system
Palmer notation (quadrant/bracket system)
FDI World Dental Federation notation (two-digit system)
Instructor’s emphasis on familiarity and practical use for exams:
You’ll be given permanent and primary designations to map out tooth types.
You should be able to identify arch, class (anterior vs posterior), and tooth type from a given numbering scheme.
Universal numbering system (as discussed in the transcript)
Transcript statement: “Universal is one through sixteen, seventeen through 32. That’s the easiest.”
Interpretation from the lecture:
The numbers are presented as split across arches (1–16 and 17–32) in the talk, implying an arch-based split.
Note: In standard practice, the Universal system uses two-digit numbering 1–32 for permanent dentition (and A–T for primary dentition). The instructor’s phrasing reflects a classroom shorthand that ties to the two-arch layout.
What you should be able to determine from a universal tooth number:
Whether the tooth is in the upper (maxillary) or lower (mandibular) arch
Whether the tooth is anterior or posterior
The tooth type (incisor, canine, premolar, molar)
If it’s molar or premolar, which order (first, second, or third)
Practical note from the lecture:
The teacher says: “I gave you the universal numbering. I want you to tell me what kind of tooth it is.”
You’ll need to map a given universal number to the appropriate tooth characteristics.
Palmer notation (quadrant/bracket system)
Concept introduced:
Uses a quadrant identifier and a surface number (1–8) within the quadrant.
There are two presentation styles the instructor mentioned:
One style uses a quadrant number followed by the tooth number (two spaces) to indicate the tooth position.
The other style uses brackets to denote the arch/quadment, i.e., a bracket around the quadrant section.
Permanent vs primary distinction:
The quadrant number range differs between permanent and primary in Palmer notation, typically 1–4 for permanent and 5–8 for primary in the first digit when discussed in some curricula.
What you should be able to read from Palmer notation:
Identify the quadrant, then the tooth position (1–8) within that quadrant, and thus determine the tooth identity.
FDI numbering system (two-digit notation)
Structure described in the transcript:
First digit indicates the quadrant (and dentition type):
Permanent dentition quadrants: 1–4
Primary dentition quadrants: 5–8
Second digit indicates the tooth position within the quadrant: 1–8
What you should be able to determine:
From a two-digit FDI code, identify:
Maxillary vs. mandibular (based on quadrant number and common mapping)
Anterior vs. posterior (based on the tooth position)
Tooth type (incisor, canine, premolar, molar) and which number (e.g., 1st, 2nd, or 3rd) when applicable
The transcript reinforces that you’ll be given marks in both the permanent and primary systems and must label accordingly.
Summary of what to memorize for part two
Three numbering systems to understand and translate between:
Universal:
Permanent: (classically) with arch-based grouping in the lecture phrasing; primary often denoted differently in other curricula (A–T). In the lecture, you should be able to say maxillary vs mandibular, anterior vs posterior, and tooth type from a universal number.
Palmer notation: quadrant-based with a position 1–8 within each quadrant; two presentation styles (quadrant+spaces or bracketed).
FDI notation: two-digit code; first digit = quadrant (permanent , primary ); second digit = tooth position within quadrant .
You must be able to determine from a universal number:
Arch (maxillary vs mandibular), anterior vs posterior, tooth type (incisor, canine, premolar, molar), and if molar/premolar, first/second/third.
You should be able to map and compare across systems for a given tooth designation.
Part Two: Additional Dentition Content and Key Concepts
Part two tasks are emphasized as the first portion of testing; part one comes after.
Strategy shared:
Use notes you’ve prepared to answer part two first, then pull out notes for part one.
Calculation of test percentage (grading context):
After grading, to compute your percentage score, use the formula:
Note on exam logistics:
The instructor mentions manually grading and entering points to compute the percentage.
Key dental anatomy and terminology referenced in the transcript
CEJ (cemento-enamel junction):
The boundary between enamel and cementum on a tooth.
Dentition types and periods:
Primary dentition (deciduous teeth; baby teeth)
Mixed dentition (presence of both primary and permanent teeth)
Permanent dentition (adult teeth)
Periods and their landmarks:
Beginning of mixed dentition: typically marked by eruption of the first permanent teeth (commonly the first permanent molars in many curricula; teach focuses on the fact that the first permanent teeth’ eruption signals the start of mixed dentition).
End of primary dentition: when the last primary tooth is shed, and permanent teeth populate the arch.
Structural/occlusal anatomy concepts:
Clinical crown vs. anatomic crown:
Anatomic crown: portion of the tooth covered by enamel from the clinical crown boundary to the cementoenamel junction.
Clinical crown: portion of the tooth that is visible in the mouth; can be longer or shorter depending on gingival recession.
Enamel vs. cementum: enamel covers the crown; cementum covers the root.
Division of dental arches:
Maxillary (upper) and mandibular (lower) arches.
Division into left/right halves via a midline, or into two or three sections relative to landmarks.
Proximal height of contour: the greatest height of contour on the proximal surfaces of a tooth.
Terminology for primary teeth:
Primary dentition terms: deciduous, succedaneous (note: in the context, the term succedaneous refers to permanent teeth that replace primary teeth; some primary teeth are non-succedaneous).
Appearance differences: primary vs permanent dentition difference in appearance (shape, size, color) noted as part of identification.
Tooth surfaces terminology:
Mesial, distal, buccal (or labial), lingual (or palatal for maxillary teeth).
Tooth numbering systems vs designation systems:
Clarification that terms like “tooth designation system” are interchangeable with “tooth numbering system.”
Dental arch division strategies:
Division into two parts (halves) or three parts (sections) depending on landmark used.
Tooth function by type:
Incisors: cutting; canines: tearing; premolars and molars: grinding/masticatory function.
Transitional dentition concept:
Transitional dentition refers to the mixed dentition period where both primary and permanent teeth are present; the teacher notes that the term is used interchangeably with mixed dentition for the context of tooth types.
Embrasures and masticatory surfaces:
Embrasures: the triangular spaces around the contact areas between adjacent teeth.
Masticatory surfaces: chewing surfaces of posterior teeth.
Linear elevations on masticatory surfaces: refers to ridges or elevations formed by the cusp ridges and grooves on chewing surfaces.
Long axis of a tooth:
Described as the line that represents the long axis of a tooth (used in reference to positioning and orientation).
Pit groups:
Terminology related to pits and fissures on tooth surfaces (pits and grooves are common features on chewing surfaces).
Practical reminders for exam preparation
Expect an image on the test with missing letters E and F (the instructor says to disregard those options and focus on other letters).
Be prepared to identify enamel, dentin, pulp, and cemento-dentinal structures as part of the labeling task.
Use the three numbering systems to cross-check tooth identity quickly during the exam.
Review the criteria for classifying teeth into incisor, canine, premolar, molar, and then determine first/second/third in molars or premolars when applicable.
Know the distinction between clinical and anatomical crowns and how gingival recession affects visibility and measurement.
Quick reference prompts you can use while studying
If given a universal tooth number, determine:
Arch (maxillary or mandibular), type (anterior/posterior), and tooth category (incisor/canine/premolar/molar) and if molar/premolar, which order.
If given a Palmer notation, identify:
Quadrant and tooth position (1–8) within that quadrant; translate to universal or FDI as needed.
If given an FDI code, identify:
Quadrant (1–4 permanent, 5–8 primary) and tooth position within quadrant (1–8); then determine arch, anterior/posterior, and tooth type.
Note on terminology alignment
The transcript presents some terminology in a classroom shorthand that combines standard naming with instructor-specific phrasing. Use the standard mappings as a baseline, but be comfortable interpreting the instructor’s cues (e.g., split universal arches, bracket vs non-bracket Palmer formats).
Always be able to translate any tooth designation you’re given into the three system formats for quick cross-checks on exams.