Maybe the first though crossing someone’s mind would be that this post makes no sense. However, daily conversations with friends or patients suggest that there is a lot of confusion on this subject. In general we do not know how many teeth we have and how they are called. So let us try to put things in to perspective ….
The adult human has a full set of 32 teeth ( 16 in each jaw ). These are divided into groups. If we follow an imaginary pathway from the midline towards the back of the orla cavity, we have the following groups :
- The first group are the incisors. We have four per jaw. Two central incisors , each side of the midline and two laterals, one on each side by the central incisor. These teeth are used to bite into food and cut it to smaller pieces (hence their name).
- The next group is canines. They are two in each jaw, one on the left and one on the right. Canines have a characteristic shape with their pointed tip.Their use is to shread food. FUnction and shape resemble their dog-counterparts, hence their name.
- Immediately on the posterior are the premolars. These are four in each jaw, two on the left and two on the right. Morphologically they resemble small molars. They are used in chewing food. Their name is derived from their position relative to the next set of teeth.
- The last group are the molars. These teeth that are used predominantly for the mastication of food. This group often creates the most confusion. We have six molars in each jaw, three on the left and three on the right. From front to back are the first, second and third molar . The third molar is also called wisdom tooth.
It should be emphasized that not all people have all their teeth but often are missing teeth. Wisdom teeth may not be present in the mouth because they may be impacted into bone or because there may be congenitally missing, which is quite common. Congenitally missing 2nd and 1st molars have been reported but it is even more rare. Congenitally missing premolars also usually accompanied by the retention of deciduous ( baby molars ) in place. Reports in the literature for congenitally missing canines are extremely rare and usually occur in people with Asian characteristics. More frequent are congenitally missing lateral incisors. Finally extremely rarely are missong cetral incisors.
And of course we can have and supernumerary teeth. They usually appear in the form mesodont ( hypoplastic teeth present in the area between the two central incisors ) or paramolars ( small molars – dwarfs shown either in the buccal surface of a molar or near the wisdom teeth . Sometimes these teeth are impacted . Cases with fully formed supernumerary teeth, impacted or not, is extremely rare, but there are references in international literature.