Tooth numbering systems
Introduction to Dental Anatomy
Overview of the Lecture
- Thanked viewers for their support and expressed a commitment to helping dental students globally. The focus is on understanding dental studies to become competent professionals.
- Introduced the topic of dental anatomy, specifically the tooth numbering system, emphasizing its importance due to common student confusion.
Dental Formula Basics
- Explained that the lecture will cover the dental formula first, followed by various tooth numbering systems: universal, PAMA, and FDI systems.
- Clarified that the dental formula represents only one side of each jaw (maxillary and mandibular), simplifying memorization for students.
Understanding Dental Formula
Components of Dental Formula
- Discussed three key factors in a dental formula:
- Denomination of teeth using initial letters (e.g., 'i' for incisor, 'c' for canine).
- A horizontal line separating maxillary from mandibular teeth.
- The number of each type of tooth indicated above or below this line.
Deciduous Dentition
- Described the composition of deciduous dentition:
- Two incisors on each side in both maxilla and mandible.
- One canine on each side in both arches.
- Two molars on each side in both arches.
- Total count per side is five teeth in both maxilla and mandible for deciduous dentition.
Permanent Dentition Overview
Composition of Permanent Teeth
- Outlined permanent dentition structure:
- Two incisors on each side (maxillary and mandibular).
- One canine per arch on either side.
- Two premolars per arch on either side.
- Three molars per arch on either side.
- Total number of permanent teeth is sixteen (eight maxillary and eight mandibular) per quadrant.
Tooth Numbering Systems
Importance and Types
- Emphasized the need for a tooth numbering system for maintaining accurate records; introduced three main systems: universal notation, PAMA system, FDI system.
Universal Notation System Explained
- Detailed how to divide quadrants using a horizontal line (maxillary vs mandibular) and midline (right vs left).
- Provided a mnemonic involving an "L" shape formed in one quadrant to help remember left versus right sides effectively.
Deciduous Dentition Notation
Universal Notation Systems for Dental Dentition
Deciduous Teeth Notation
- The universal notation system for deciduous dentition starts with a dividing line between maxillary and mandibular teeth, and a vertical line separating the right from the left side. The maxillary right quadrant begins with the second deciduous molar marked as A, followed by B (first molar), C (canine), D (lateral incisor), and E (central incisor) .
- Continuing to the maxillary left quadrant, the central incisor is marked as F, lateral incisor as G, canine as H, first molar as I, and second molar as J. This completes the notation for all maxillary teeth .
- For mandibular teeth, notation starts from the left quadrant: K (second molar), L (first molar), M (canine), N (lateral incisor), O (central incisor). This concludes the mandibular left quadrant notation .
- In the mandibular right quadrant, teeth are noted as follows: P (central incisor), Q (lateral incisor), R (canine), S (first molar), T (second molar). The complete alphabet used in this system ranges from A to T for deciduous dentition across both arches .
Permanent Teeth Notation
- Transitioning to permanent teeth notation, numbers 1 through 32 replace letters. The same horizontal and vertical lines divide maxillary from mandibular and right from left sides respectively. Starting with maxillary right quadrant: 1 is third molar, 2 is second molar, 3 is first molar up to 8 which represents central incisors in this section .
- Continuing with maxillary left quadrant numbering: Central incisor is noted as 9; lateral incisor as 10; canine as 11; first premolar as 12; second premolar as 13; first molar at 14; second at 15; third at 16. This completes all maxillary permanent teeth notations .
- Finally completing the mandibular right quadrant: Central incisor is noted as 25; lateral incisors are marked with number26 through to third molars being numbered sequentially up to number32. This provides clarity on permanent tooth identification using this universal system .
Parma Notation System Overview
Parma Notation for Deciduous Teeth
- In Parma notation for deciduous dentition:
- A denotes central incisors,
- B denotes lateral incisors,
- C denotes canines,
- D denotes first molars,
- E denotes second molars.
Application of Parma Notation
- To denote specific teeth within this system:
- For example, marking a maxillary right side canine involves drawing a plus sign followed by C.
- Similarly marking a mandibular left side second molar would involve drawing a plus sign followed by E.
Permanent Dentition in Parma Notation
- In contrast to deciduous dentition where letters are used, permanent dentition utilizes numbers:
- One represents central incisors,
- Two represents lateral incisors,
- Three indicates canines,
- Four marks first premolars,
- Five signifies second premolars,
- Six identifies first molars.
Dental Notation Systems Explained
Understanding Tooth Numbering Systems
- The second molar is represented by the number seven, while the third molar is represented by eight in dental notation. To denote the mandibular second premolar, it should be drawn below a horizontal line indicating the mandibular quadrant.
- The second premolar is indicated on the right side of a diagram forming an "L" shape, with the mandibular second premolar represented by number five. For example, to note the maxillary left canine, one must draw a plus sign indicating maxillary teeth.
- The FDI notation system proposed by the Federation Dentaire Internationale (FDI) uses a two-digit format and is recognized by WHO. This system does not utilize a plus sign and is more compatible for data storage.
Quadrant Representation in FDI System
- In the FDI system, each tooth receives a two-digit code where the first digit indicates the quadrant number. Quadrants are numbered as follows: 1 for maxillary right, 2 for maxillary left, 3 for mandibular left, and 4 for mandibular right.
- For deciduous dentition (baby teeth), quadrants are labeled starting from maxillary right as five through eight: 5 (maxillary right), 6 (maxillary left), 7 (mandibular left), and 8 (mandibular right).
Detailed Tooth Notation Examples
- In permanent dentition using FDI notation:
- Maxillary Right Quadrant: Central incisor = 51; Lateral incisor = 52; Canine = 53; First molar = 54; Second molar = 55.
- Maxillary Left Quadrant: Central incisor = 61; Lateral incisor = 62; Canine = 63; First molar = 64; Second molar = 65.
- Mandibular Left Quadrant: Central incisor = 71; Lateral incisor = 72; Canine = 73; First molar = 74; Second molar = 75.
Mandibular Right Quadrant: Central incisor =81; Lateral incisor =82; Canine=83; First molar=84; Second molar=85.
Dominant Dentition Notation
- In dominant dentition:
- Maxillary Right Quadrant: Central incisor noted as "11", lateral as "12", canine as "13", first premolar as "14", second premolar as "15", first molar as "16", second molar as "17", third molar as "18".
- Maxillary Left Quadrant follows similarly with numbers starting from two ("21" to "28"). Mandibular Left and Right quadrants follow suit with respective numbering conventions ("31" to "38" and "41" to "48").
Practice Questions on Dental Notation
- Students are encouraged to practice their understanding of these systems through quizzes designed to reinforce knowledge about tooth identification based on various notation systems.