title: On the incidence patterns of PMA index in the elementary school children--with reference to its transition processes.
mesh_terms: D000367:Age Factors; D002648:Child; D005891:Gingivitis / Q000453:epidemiology* / Q000473:pathology; D006801:Humans; D010512:Periodontal Index; D013997:Time Factors; D014070:Tooth / Q000473:pathology