According to the universal system, the tooth that is denoted by the number 23 is
The tooth designated "1" is the maxillary right third molar and the count continues along the upper teeth to the left side. Then the count begins at the mandibular left third molar, designated number 17, and continues along the bottom teeth to the right side Ref - https://en.m.wikipedia.org/wiki/FDI_World_Dental_Federation_notation
Upper left temporary canine
Lower left permanent lateral incisor
Lower right first premolar
Upper left permanent canine
Identification