Tus mandibular thawj premolar yog tus hniav nyob laterally (tawm ntawm nruab nrab ntawm lub ntsej muag) los ntawm ob qho tib si mandibular canines ntawm lub qhov ncaujtab sis mesial (mus rau nruab nrab ntawm lub ntsej muag) los ntawm ob qho tib si mandibular thib ob premolars.
Cov premolars nyob rau ntawm lub puab tsaig nyob qhov twg?
Cov premolars, tseem hu ua cov hniav premolar, lossis bicuspids, yog cov hniav hloov pauv nyob rau nruab nrab ntawm cov hniav canine thiab molarHauv tib neeg, muaj ob lub premolars ib quadrant nyob rau hauv cov txheej txheem tas mus li. hniav, ua yim premolars tag nrho nyob rau hauv lub qhov ncauj. Lawv muaj tsawg kawg yog ob cusps.
Cov premolars nyob qhov twg?
Premolars, tseem hu ua bicuspids, yog cov hniav nyob ruaj khov nruab nrab ntawm cov molars nyob rau hauv qab ntawm koj lub qhov ncauj thiab koj cov hniav tsiaj, los yog cuspids, nyob rau hauv pem hauv ntej. Vim tias premolars yog cov hniav hloov pauv, lawv pom cov yam ntxwv ntawm cov molars thiab canines thiab feem ntau zom thiab zom zaub mov.
Dab tsi yog ob hom mandibular thib ob premolars?
Ob daim ntawv ntawm mandibular thib ob premolars yog ob-cusp thiab peb-cusp forms.
Yuav ua li cas premolar feem ntau yuav muaj 3 cusps?
Kev Ntsuas: Lub mandibular thib ob premolar feem ntau muaj peb lub cusps tab sis tuaj yeem muaj ob qho tib si.
