Universal Numbering System (deciduous teeth) (English)

The Universal Numbering System for the deciduous or primary dentition follows the same pattern as with the permanent teeth, however the uppercase letters A - T are used instead of numbers. The maxillary right second molar receives the letter ‘A’ then the alphabet runs through the maxillary arch until reaching the maxillary left second molar which receives the letter ‘J’. Regarding the mandibular or inferior arch, the mandibular left second molar receives the letter ‘K’ with the alphabet continuing across the mandibular arch until reaching the mandibular right second molar which receives the letter ‘T’. Alternatively, the deciduous teeth are sometimes notated by the numbers 1-20 with a lowercase ‘d’ added to indicate a deciduous tooth (Woelfel system).