Pedodontist is a word that was used for some time to describe the specialty of dentistry devoted to the treatment of children. “Pedia-“or “Pedo” means child or children; “-dontist” denotes one who studies teeth. The old word was found to be confusing. Some people thought it meant foot doctor or something. The modern accepted term these days is Pediatric Dentist or Pediatric Dentistry. The term was changed a few years ago, but you will still hear the older term. Pediatric Dentistry is an age-defined specialty that provides both primary and comprehensive preventive and therapeutic oral health care for infants and children through adolescence, including those with special health care needs.
I came across google “ngrams” search engine. This searches millions of books published over the years and finds certain terms or phrases. See if you can see when one term fell out of favor and the other is now accepted.
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