Before proceeding please make sure to subscribe and turn on the bell icon for upcoming videos. Hello and in today's video we will look at an introduction to the primary and permanent dentitions and their numbering systems. So let's begin.
Human have two sets of teeth namely the deciduous and the permanent teeth. The deciduous teeth begin at about 14th week of intrauterine life and is completed postnatally at three years of age. The first primary tooth begins to erupt at the mean age of six months and the last to erupt is at 28 plus minus four months. Then there comes a time where the primary teeth starts to shed and their space is occupied by their permanent successors. It's called the mixed dentition period.
Permanent teeth erupted in the spaces of primary teeth are called successors or succidinous teeth because they replace the primary teeth. Therefore any permanent teeth emerging and replacing the primary teeth will be the permanent successor of the corresponding primary tooth and any permanent teeth emerging in a place other than the place of the deciduous teeth will not be a successor but just a permanent tooth like in case of permanent molars Now let's move on to the tooth numbering systems. The two sets of teeth as said before were the primary dentition and the permanent dentitions. Other common terms used for primary dentitions are the deciduous teeth, milk teeth and baby teeth.
The primary teeth in each jaw is 10 in number. Counting within each quadrant we have got three anterior teeth which are the central, lateral and canine and only two posterior teeth which are the first and the second molars. Permanent dentition are 32 in number.
Counting within each quadrant we have got one central, one lateral incisor, one canine, two premolars and three molars making up eight teeth in a quadrant and a full set of 32 teeth in the entire mouth. Teeth are numbered for the purpose of an easy communication amongst the dental staff so that they could refer to each tooth quickly saving them time and creating less confusion. There are three well-known tooth numbering systems known as Universal Numbering System, Palmer's Numbering System and FDI Tooth Numbering Systems.
Each system has got its own unique advantages. Let's now study each one of them in detail. In the Universal Numbering System which is known the mostly used numbering system, in this system the maxillary teeth are numbered from one to 16 starting from the maxillary right third molar and ending at maxillary left third molar. The mandibular teeth are numbered from 17 to 32 beginning from left mandibular third molar and ending at right mandibular third molar.
We begin with the maxillary arch starting from the maxillary right third molar. We move along the same arch Then we jump in the lower arch starting from the side we ended in the upper arch and we move back towards the right. And finally we end at the lower right mandibular third molar.
In short, the start point in this system is the maxillary right side and the end point is the mandibular right side. For primary dentition, instead of numbers we use alphabets. and the universal numbering system for primary teeth is as follows.
Beginning with A, the upper right maxillary second molar goes sequentially in the same arch up to J, which represents upper left maxillary second molar. We drop down on the same side to K, which represents mandibular second molar, and then we move in a clockwise position and end at T, which represent the right mandibular second molar. The universal numbering system for the entire primary and permanent indentation is as follows.
Coming up to the next system is the Palmer system also called the Zygmunti system. This system was first presented by Adolf Zygmunti in the year 1861 where he used a Zygmunti cross to record quadrants. This system was later modified by Palmer and then he termed it the sigmundi palmer notation Palmer system is a four quadrant tooth numbering system.
In this system the dentition is divided into four quadrants by a vertical line at the mid-sagittal plane and a horizontal line separating the upper and lower jaws. Each quadrant is assigned a specific symbol which represents that quadrant. The symbol surrounds a specific alphabet or number denoting the number of either primary or permanent tooth.
Denoting permanent teeth, the tooth closest to the midline is denoted as tooth number one of the corresponding quadrant. For example, the central incisor is designated tooth number one and represents the first tooth in the quadrant while the third molar designated as tooth number eight represents the last tooth in the quadrant. The entire permanent dentition in palmar system is represented as follows.
The palmar notation for primary dentition is denoted by alphabetical form and with capital letters. The alphabet A represents the first tooth in each quadrant which is the central incisor. and the letter E represents the last tooth in each quadrant which is the second molar. The entire primary dentition in Palmer's system is represented as follows. What we can observe here is that unlike Palmer's system, the universal system is more acceptable to computers and creates much less confusion.
Therefore, the universal tooth numbering system was officially recommended by American Dental Association in the year 1968. The last system we have is the FDI or World Dental Federation system. The FDI system is a two-digit truth numbering system and has been accepted by WHO and other well-known organizations. In this system the first number among the two digits indicates the number of the quadrants. In permanent teeth the number one represents the first quadrant.
which is the maxillary right quadrant. Number two represents maxillary left quadrant. Number three for mandibular left quadrant and finally number four which represents the mandibular right quadrant.
The second number of the two number digit is the twelfth number within that quadrant starting from For example, the number 11 stands for the maxillary right central incisor in the first quadrant and number 21 represents the maxillary left central incisor in the second quadrant. The numbers are pronounced as 11 or 21, not 11 or 21. In FDI system, the entire permanent dentition is represented as follows. In FDI system for primary dentition, the first digit which presents the quadrants starts from 5 to 8 in a clockwise manner. the number five for maxillary right quadrant number six for maxillary left quadrant number seven for mandibular left quadrant and finally number eight for mandibular right quadrant. The second digit represents the tooth within that quadrant it starts from one to five with the digit one representing the central incisor and digit five representing the second molar in that quadrant.
The FDI truth numbering system for the entire primary dentition is represented as follows. I hope this video helps. If you think this video was really helpful please do like, subscribe, share and comment if you have any questions. Thank you for watching.