Periodontal disease is common around the world, with the World Health Organization classifying it as a major public health problem due to its high prevalence and links to systemic chronic conditions, such as cardiovascular diseases, diabetes and respiratory illnesses.
In China, the burden is particularly acute. A combination of poor oral hygiene, high tobacco use, issues with nutrition and limited access to preventive dental care, means that gum disease strikes early and frequently. Among adults aged 25 to 44 years old, around 87% have bleeding gums, and 97% had calculus buildup — both early signs of gum disease 1.
“To improve population-level outcomes, the challenge is to make existing oral hygiene habits do more,” says Henglong Hu, head of R&D at Haleon China, the Shanghai-based division of the global consumer health company.
Rather than focusing on treating the symptoms of gum disease, research teams at Haleon are collaborating with academic and clinical experts to investigate how boosting everyday oral care might prevent disease onset. Their work ranges from laboratory studies of plaque formation and targeted antimicrobial treatments to clinical trials, which are designed to understand which treatments work in the real world.
Root cause
Long before gums start to bleed, dental plaques — a type of biofilm — begin to form. This dense, structured matrix of bacteria and extracellular substances accumulates along the gumline, sticking tightly to tooth surfaces — much like the gunk around a kitchen drain. The plaque triggers low-grade inflammation in the gum tissues, marking the earliest stage of gum disease, known as gingivitis.
“The inflammation is present, but the pain is intermittent and mild. Most people don’t realize the damage until it’s too late,” says Hu. If left untreated, the plaque buildup may progress to full-blown periodontitis, with irreversible damage to the bone and connective tissues that keep teeth in place. This can also lead to persistent bad breath, gum recession and tooth loss. The link between gum disease and chronic diseases like diabetes is also a cause for concern.
“More effective daily brushing lets us intervene before problems worsen,” Hu explains. However, standard toothpaste formulations have struggled to combat plaque. Many toothpastes are designed to alleviate symptoms such as bleeding or swelling, rather than disrupt the biofilm, Hu adds.
Fortress plaque
In their investigations of alternative toothpaste formulations, Haleon’s researchers turned their attention to sodium bicarbonate, a compound used in oral care since the 19th century. “Bicarbonate has long been part of dental formulations,” says Hu. “But its full potential is now being re-examined with modern experimental tools.”
To study the effect of high concentrations of sodium-bicarbonate on plaques of different maturity, the researchers used a constant-depth film fermenter — a laboratory device that allowed them to grow biofilms under a continuous flow of artificial saliva.
In laboratory cultures of 7- and 14-day-old plaques, viable bacteria dropped by about 1,000-fold following a two-minute treatment with a sodium bicarbonate slurry, leaving just 0.1 % of the original population2. Interestingly, the slurry was not effective on 2-day-old plaques.
Microscopy explained the trend: the younger biofilms had a multi-layer ‘fortress’ architecture, whereas the mature biofilms had collapsed into isolated bacterial clusters less tightly attached to the tooth surface.
“The bicarbonate does not kill bacteria,” explains Hu. “Instead, it breaks down the extracellular polysaccharide scaffold that glues mature plaque together, making it easier to remove by brushing without disturbing the overall microbial balance.”
Stable actives
But achieving a stable toothpaste formulation with such high concentrations of sodium bicarbonate posed significant technical challenges. For example, formulations were difficult to mix, and the researchers observed unexplained colour changes in the paste.
They conducted a series of gradient-based screenings, within the technically feasible range. The formulation with 67% sodium bicarbonate demonstrated a favourable balance between biofilm removal efficacy and stability. Crucially, it remained compatible with fluoride — active in toothpaste for cavity prevention and enamel strengthening — which was difficult to incorporate at high active loads. Sensory properties were another constraint — high concentrations of sodium bicarbonate produce a strong salty-metallic taste.
“We tested more than a dozen prototypes with different sensory profiles,” Hu recalls. “It took multiple rounds of adjustment to balance function and acceptability without compromising formulation integrity.”
Since settling on the formulation, Haleon has run more than 15 randomized controlled trials across North America, Europe and Asia, enrolling more than 5,000 participants with mild-to-moderate gingivitis. For example, a six-month trial in United States, tested the effect of twice-daily brushing with a 67% sodium bicarbonate toothpaste on gum bleeding and gingivitis3.
“We’ve monitored effects not just in controlled settings, but across populations and geographies,” Hu adds.
A separate meta-analysis reviewed seven independent studies investigating the use of 67% sodium bicarbonate toothpaste in the context of plaque and gingival health. The analysis compared formulations with and without 67% sodium bicarbonate over 12- and 24-weeks periods, examining differences in plaque levels, gum bleeding and signs of gingival inflammation4.
Early start
Hu and his team continue to investigate how oral care can shift in the direction of earlier and more targeted prevention of gum disease. One research project is investigating formulations that might alter the mouth’s microbiome with the aim of rebalancing bacterial populations to promote a healthier oral environment. Targeted antimicrobial approaches — designed to selectively inhibit pathogenic bacteria without disrupting beneficial one — are also under investigation.
Meanwhile, in response to consumer demand and for environmental sustainability, the Haleon research team is investigating naturally derived ingredients and environmentally conscious formulation strategies, such as reducing the amount of non-recycled plastic used, exploring alternative recyclable materials, and innovating with new packaging formats.
With so many research avenues to explore, the Haleon team is also considering how to speed up future discoveries. Future work will use AI to predict and optimize combinations of ingredients according to the oral microbiome that are common in a particular region, says Hu.
Haleon may have myriad innovations in its pipeline, but the ultimate goal is not simply to explore new toothpaste ingredients and delivery systems, says Hu. It’s embedding these innovations into the everyday oral hygiene routines where gum disease quietly begins.
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