People have used tongue-scraper(刮舌器)s since at least the Roman era. Napoleon Bonaparte’s was made of silver(拿破仑的刮舌器是银制的). George Washington took his everywhere. Today “influencers” like Hailey Bieber and Gwyneth Paltrow scrape their tongues as part of their “wellness(养生；健康生活方式)” routines. But does tongue-scraping add anything to(为……增添价值) dental hygiene(口腔卫生) that brushing and floss(用牙线清洁)ing can’t do alone?
至少从罗马时代起，人们就开始使用刮舌器。拿破仑·波拿巴的刮舌器是银制的，乔治·华盛顿则随身携带。如今，海莉·比伯、格温妮丝·帕特洛等“网红”把刮舌当作“养生”日常的一部分。但刮舌对口腔卫生的贡献，真的能超过刷牙和用牙线吗？
The mouth, like the gut, is home to lots of microbe(微生物)s. A healthy oral microbiome(微生物组) includes around 700 species of bacteria, along with fungi, protozoa(原生动物) and viruses. But poor oral hygiene, smoking or bad diet can upset the balance(打破平衡). That results in bacterial colonies, called biofilms, in which species thrive that cause tooth cavities, gum disease and chronic bad breath (halitosis).(这会导致细菌群落（即生物膜）形成，其中滋生的菌种会引发蛀牙、牙龈疾病和慢性口臭。)
口腔和肠道一样，是大量微生物的家园。健康的口腔微生物组包含约700种细菌，以及真菌、原生动物和病毒。但口腔卫生差、吸烟或饮食不良会打破这种平衡，导致细菌群落（即生物膜）形成，其中滋生的菌种会引发蛀牙、牙龈疾病和慢性口臭。
Biofilms are the basis of dental plaque(牙菌斑), which forms because teeth, unlike the mouth’s other tissues, are not constantly shed(脱落；蜕落)ding their cells, and thus any bacteria clinging to them. But tongues, which host about two-thirds of the oral microbiome, are also susceptible(易受影响的；易感的) to biofilms—which can turn them white or yellow. The gaps between the tiny protuberances covering a tongue’s upper surface teem with bacteria and are especially hospitable to anaerobic species, the respiration of which does not require oxygen but does often generate foul-smelling sulphurous compounds.(舌头表面布满微小突起，突起之间的缝隙里细菌密集，尤其适合厌氧菌生存；这类细菌的呼吸不需要氧气，却常常产生带有恶臭的含硫化合物。)
生物膜是牙菌斑的基础。牙菌斑之所以形成，是因为牙齿与口腔其他组织不同，不会不断脱落细胞，因此细菌得以附着其上。但舌头——口腔微生物组约三分之二栖息于此——同样容易形成生物膜，使舌面变白或变黄。舌头表面布满微小突起，突起之间的缝隙里细菌密集，尤其适合厌氧菌生存；这类细菌的呼吸不需要氧气，却常常产生带有恶臭的含硫化合物。