NANJING -- At a Sanxiao toothbrush factory in East China's Jiangsu province, employees were carefully monitoring robotic arms performing precise injection molding on the production line, while in an adjacent exhibition hall, another employee was busy attending a video call with an overseas client.

Sanxiao Group is a prominent member among approximately 2,000 enterprises that anchor the toothbrush industry in Hangji township, Yangzhou city. This industrious township, occupying less than 40 square kilometers, produces 7.5 billion toothbrushes annually, with the products exported to over 80 countries and regions.

Interestingly, one out of every three toothbrushes worldwide comes from Hangji, which was aptly named "China's toothbrush capital" by the China National Light Industry Council in 2003.

The roots of Hangji's toothbrush manufacturing industry stretch back to the late Qing Dynasty (1644-1911) when an innovative farmer revolutionized toothbrush design by crafting them with ox bones and pig bristles.

For a long time, the toothbrush industry was viewed as a low-margin sector, constrained by a short industrial chain and meager profits, according to industry insiders. However, this once-underestimated industry has been at the forefront of a silent revolution in recent years, driven by increased efficiency, technological advancements and innovative ideas.

"We have invested 1 billion yuan ($140 million) in constructing our new smart factory," said Han Xiaotian, assistant to the chairman of Sanxiao Group. "Equipped with intelligent robots, automated assembly lines and a smart management system, our factory operates non-stop, with production efficiency up by some 50 percent."

Innovation has been a key catalyst in driving the transformation of this industry. Yangzhou Sanfeng Brush Co Ltd, in collaboration with a leading artificial intelligence (AI) research company from south China's Shenzhen, has recently developed an AI-powered electric toothbrush. This smart device features a display screen and an embedded sensor, enabling it to interact with users and transmit oral health data to a mobile app.

The innovative toothbrush has already received orders from countries such as Switzerland and Russia, said Li Yang, chairman of Sanfeng. He anticipates that the new product will achieve annual sales revenue of about 150 million yuan at full capacity.

Oral-care products from Hangji have gained recognition in various settings, including European dental clinics, luxury hotels in Dubai and the research icebreaker Xuelong, which supports Chinese polar expeditions. Customized toothbrushes have helped protect researchers from bleeding gums in polar regions.

Creativity has also propelled the development of Hangji's toothbrush industry. A toothbrush with a waistline-shaped handle and a base resembling a traditional Chinese landscape painting, developed by Minsheng Brush Daily Chemical Co Ltd, has become an international hit. "We draw inspiration from traditional Chinese culture to enhance the aesthetic value of our products for our customers," said Zhang Degang, head of the company, noting that 90 percent of their products are exported to other countries.

As domestic and international markets become saturated, Hangji is encouraging entrepreneurs to expand into higher value-added sectors. Jiangsu Golden Material Technology Co Ltd, after a decade of specializing in toothbrush packaging, is now venturing into the polymer material field. "We have developed a proton exchange membrane, a core component of hydrogen fuel cells, and expect to achieve mass production this year," said Xie Sihai, the company's general manager.

With 15 innovative polymer packaging material producers, Hangji is now targeting emerging industries such as automated equipment manufacturing and smart energy storage, marking a new chapter in its industrial evolution.