Chapter 15 (Partial Transcript): Dentition, Tooth Types, and Universal Numbering System

Learning Objectives

• $2$ Describe the two dentitions and the relationship to each other.
• $1$ Define and pronounce the key terms in this chapter.
• $3$ Recognize tooth types and outline the tooth numbering systems.
• $4$ Assign the correct universal or international number for a tooth and its correct dentition period on a diagram or a skull and for a tooth model or a patient.
• Concerning each dentition period, integrate it into patient care.
• $6$ Use the correct dental anatomy terminology and discuss the clinical considerations concerning tooth anatomy, integrating it into patient care.
• $7$ Use the correct orientational tooth terms and discuss the clinical considerations concerning tooth surfaces, integrating it into patient care.
• $8$ Identify tooth forms and discuss the clinical considerations concerning them, integrating it into patient care.

Dentition overview

• The dentition is the natural teeth in the jaws.
• There are $2$ dentitions during a lifetime: a primary dentition and a permanent dentition.
• The goal of every dental professional is to keep each dentition healthy, functional, and esthetic mainly by preserving the existing teeth within it.
• Not all dentitions are healthy or functional; dentistry aims to address those cases.
• Professional practice should integrate understanding of dentition into patient care.
• Cross-references to foundational material: development relationships discussed in Chapter 6; review prior to specific tooth anatomy discussions.

Restorative treatment and prosthodontics (definitions and scope)

• Restorative treatment (ruh-staw-ruh-tuhv): repairing or replacing damaged or missing teeth within each dentition.
• A dental prosthesis (pros-thee-suhs): an intraoral replacement used to restore intraoral defects within each dentition (e.g., missing teeth or parts of teeth, missing soft or hard structures of the jaw/palate).
• Prostheses examples include veneers, crowns, dental bridges, dentures, and dental implants.
• Prosthodontics (pros-thoh-don-tiks): the dental specialty that focuses on therapy using dental prostheses.

Dentition terminology and clinical integration

• Emphasis on correct dental anatomy terminology and clinical considerations related to tooth anatomy.
• Emphasis on orientational tooth terms and tooth surfaces.
• Emphasis on tooth forms and how these influence patient care.

Primary dentition (the first dentition to develop)

• Also known as deciduous dentition (duh-sih-joo-uhs).
• The primary dentition is shed and replaced by the permanent dentition, analogous to a deciduous tree shedding leaves.
• Common patient language: “baby teeth.”
• Primary dentition development, eruption, and shedding are discussed in more detail in Chapter 6 (review before Chapter 15 discussions).

Tooth types in the primary dentition

• Primary dentition comprises teeth in both arches totaling $20$ teeth.
• Primary dentition composition in each arch: $8$ incisors, $4$ canines, and $8$ molars.
• The detailed anatomy of the primary dentition is covered in Chapter 18.
• Note: The primary dentition does not include premolars.

Permanent dentition (the second dentition)

• The permanent dentition is the second dentition to develop; it is sometimes called the secondary dentition (Fig. 15.2; see Fig. 20.1).
• Patients may refer to permanent teeth as “adult teeth.”
• The permanent dentition is not entirely succedaneous; most permanent teeth succeed primary predecessors, but not all (notably, the permanent molars do not have primary predecessors).
• Permanent dentition tooth count: $8$ incisors, $4$ canines, $8$ premolars, $12$ molars; total $32$ teeth.
• Note: Premolars exist only in the permanent dentition; the primary dentition has no premolars.
• Detailed anatomy of the permanent dentition is discussed in Chapter 16 (anterior teeth) and Chapter 17 (posterior teeth).

Tooth designation systems (Universal Numbering System, UNS)

• Both primary and permanent teeth are designated by the Universal Numbering System (UNS).
• This system is the most commonly used in the United States and can support electronic data transfer.
• Primary teeth are designated using a consecutive set of capital letters, from A through T, starting with the maxillary right.
• The excerpt notes the UNS framework for primary teeth (A–T) and references figures (e.g., Fig. 15.3) for visual guidance.
• Although the text references the primary designation explicitly (A–T), the excerpt does not complete the statement for the permanent dentition’s numeric designations in this page excerpt.

Context and references

• Figures mentioned: Fig. 15.1, Fig. 15.2, Fig. 15.3, Fig. 18.1, Fig. 20.1, Fig. 2.4.
• Chapter cross-references: Chapter 6 (development), Chapter 16 (anterior teeth), Chapter 17 (posterior teeth), Chapter 18 (primary dentition anatomy).

Additional resources

• Companion Evolve website for this book with practice exercises: http://evolve.elsevier.com/Fehrenbach/illustrated

Pronunciations and terminology (quick reference)

• Restorative treatment: ruh-staw-ruh-tuhv
• Prothesis: pros-thee-suhs
• Prosthodontics: pros-thoh-don-tiks

Miscellaneous note

• A garbled fragment appears in the transcript regarding periodontal involvement (e.g., “f the loss of Fist with the periodonti levels and vs only as bers at the membrane ite.”). This content is unclear in the provided text and is not included in these notes. If you have the original page, I can clarify that segment.

Summary of key distinctions to remember

• There are two dentitions: primary (deciduous, $20$ teeth) and permanent (adult, $32$ teeth).
• Primary dentition contains no premolars; permanent dentition includes premolars.
• The permanent dentition is not entirely succedaneous; molars do not have primary predecessors.
• The UNS designates primary teeth with letters A–T; the system is widely used in the US and supports electronic data transfer.
• Restoration and prosthodontics involve replacing or repairing teeth within each dentition using various prosthetic options.

Quick cross-check ideas for exam

• Be able to contrast primary vs permanent dentition in terms of tooth counts, presence/absence of premolars, and succedaneous nature.
• Be able to list the components included under a dental prosthesis and explain what prosthodontics covers.
• Be able to explain the rationale for preserving dentition and how that goal guides restorative decisions and patient care.