lower teeth
Refers to the teeth in the lower jaw. Common in dental and everyday contexts.
My lower teeth hurt, so I went to the dentist.
下歯の矯正を始めることにした。
I decided to start orthodontic treatment for my lower teeth.
Compound of 下 (した, 'lower') and 歯 (は, 'tooth'), with rendaku voicing of は to ば.