Mandibular second molar
The mandibular second molar is the tooth located distally (away from the midline of the face) from both the mandibular first molars of the mouth but mesial (toward the midline of the face) from both mandibular third molars. This is true only in permanent teeth. In deciduous (baby) teeth, the mandibular second molar is the last tooth in the mouth and does not have a third molar behind it. The function of this molar is similar to that of all molars in regard to grinding being the principle action during mastication, commonly known as chewing. Though there is more variation between individuals to that of the first mandibular molar, there are usually four cusps on mandibular second molars: two on the buccal (side nearest the cheek) and two palatal (side nearest the palate). There are great differences between the deciduous (baby) mandibular molars and those of the permanent mandibular molars, even though their function are similar. It is important to note that the permanent mandibular molars are not considered to have any teeth that precede it. Despite being named molars, the deciduous molars are followed by permanent premolars.
In the universal system of notation, the deciduous mandibular second molars are designated by a letter written in uppercase. The right deciduous mandibular second molar is known as "T", and the left one is known as "K". The international notation has a different system of notation. Thus, the right deciduous mandibular second molar is known as "85", and the left one is known as "75".
In the universal system of notation, the permanent mandibular second molars are designated by a number. The right permanent mandibular second molar is known as "31", and the left one is known as "18". In the Palmer notation, a number is used in conjunction with a symbol deknown as "47", and the left one is known as "37".and Stanley J. Nelson, 2003. Wheeler’s Dental Anatomy, Physiology, and Occlusion. 8th edition.