IPA: /ˌpɪə.riˈɒn.dɪst/
KK: /ˌpɪrɪˈɒndɪst/
A dental expert who focuses on the treatment and prevention of gum diseases and other conditions affecting the supporting structures of the teeth.
After experiencing gum pain, I decided to visit a periodontist for a check-up.
Periodontist → It is formed from "peri-" (meaning around) and "odous" (from Greek, meaning tooth) and "-ist" (meaning one who practices). A periodontist is a specialist who practices around the teeth, focusing on the supporting structures of the teeth.
Think of someone who specializes in care 'around' ('peri-') the 'teeth' ('odous') — that's what a periodontist does.