Anatomy and Function
- The mandibular first premolar is located laterally from the mandibular canines and mesial from the mandibular second premolars.
- It has two cusps, with the buccal cusp being large and sharp, and the lingual cusp being small and nonfunctional.
- The function of the mandibular first premolar is similar to that of canines, primarily tearing during chewing.
- There are no deciduous mandibular premolars; the deciduous mandibular molars precede the permanent mandibular premolars.
- The mandibular first premolar resembles a small canine due to its small and nonfunctional lingual cusp.
- The tearing action during mastication is the principal function of the mandibular first premolar.
Notation Systems
- In the universal system, the right mandibular first premolar is designated as 28, and the left one as 21.
- The Palmer notation uses a number and symbol to designate the quadrant; both first premolars would have the number 4, with the right one having the symbol ┐ and the left one having ┌.
- The international notation assigns the right mandibular first premolar as 44 and the left one as 34.
- The terms 'bicuspid' and 'premolar' are synonymous, but bicuspid specifically refers to a tooth with two functional cusps.
- The mandibular first premolar is an example of a premolar with only one functional cusp.
References
- Ash, Major M. and Stanley J. Nelson, 2003. Wheeler's Dental Anatomy, Physiology, and Occlusion. 8th edition.
- The content on mandibular first premolars is available on Wikipedia and can be expanded.
- This article is categorized under types of teeth and human mouth anatomy.
- The article is a stub in the dentistry and musculoskeletal system categories.
- All stub articles are included in a hidden category.
- The Wheelers Dental Anatomy, Physiology, and Occlusion book provides further information on this topic.
Identifiers
- The mandibular first premolar is identified by the FMA code 55803.
- It is an anatomical term used in dental and medical terminology.
- The tooth is marked in red in diagrams to distinguish it from other teeth.
- The premolars are absent in primary teeth; they only exist in permanent dentition.
- The mandibular first premolar is located away from the midline of the face.
Additional Information
- The tooth is part of the human musculoskeletal system.
- The content on mandibular first premolars is available on Wikipedia as a stub.
The mandibular first premolar is the tooth located laterally (away from the midline of the face) from both the mandibular canines of the mouth but mesial (toward the midline of the face) from both mandibular second premolars. The function of this premolar is similar to that of canines in regard to tearing being the principal action during mastication, commonly known as chewing. Mandibular first premolars have two cusps. The one large and sharp is located on the buccal side (closest to the cheek) of the tooth. Since the lingual cusp (located nearer the tongue) is small and nonfunctional (which refers to a cusp not active in chewing), the mandibular first premolar resembles a small canine. There are no deciduous (baby) mandibular premolars. Instead, the teeth that precede the permanent mandibular premolars are the deciduous mandibular molars.
| Mandibular first premolar | |
|---|---|
 Mandibular first premolars of permanent teeth marked in red. There are no premolars in primary teeth. | |
| Identifiers | |
| FMA | 55803 |
| Anatomical terminology | |
Sometimes, premolars are referred to as bicuspids. Even though the terms are synonymous, "bicuspid" refers to having two functional cusps, and the mandibular first premolar is an example of a premolar with only one functional cusp. Thus, "bicuspid" is technically not as accurate as "premolar".
In the universal system of notation, the permanent mandibular premolars are designated by a number. The right permanent mandibular first premolar is known as "28", and the left one is known as "21". In the Palmer notation, a number is used in conjunction with a symbol designating in which quadrant the tooth is found. For this tooth, the left and right first premolars would have the same number, "4", but the right one would have the symbol, "┐", over it, while the left one would have, "┌". The international notation has a different numbering system than the previous two, and the right permanent mandibular first premolar is known as "44", and the left one is known as "34".
