A gentler way to treat aggressive gum disease

For years, treating gum disease has meant scraping away plaque, cutting out damaged tissue or turning to antibiotics that kill bacteria indiscriminately. While newer therapies can regenerate lost tissue, doctors still lack a precise way to stop the infection without harming the mouth’s healthy microbiome.

New research from the University of Florida College of Dentistry offers a breakthrough. Researchers have discovered that the primary bacterium driving gum disease carries an internal “genetic brake” that controls its own aggression. By locking this brake in place, future treatments could silence the pathogen while leaving beneficial bacteria untouched.

The study, led by oral biologist Jorge Frias-Lopez, Ph.D., focused on Porphyromonas gingivalis. Scientists call this bacterium a keystone pathogen. Like a social media influencer, its power comes from swaying the crowd. Even in small amounts, P. gingivalis can manipulate the entire microbial community, turning a healthy mouth into a diseased one.

This microscopic troublemaker drives a massive public health challenge. In the United States alone, gum disease affects about 42% of people over 30 — roughly 2 in every 5 adults. It’s also a leading cause of tooth loss, destroying the bone that supports the teeth.

Beyond the physical toll, the economic impact is staggering: the U.S. loses over $150 billion annually to the disease, mostly from lost productivity as people miss work for treatment. To find a better solution, Frias-Lopez’s team looked inside the bacterium’s own genetic instruction manual, zeroing in on a specific section called a CRISPR array.

While CRISPR is famous as a gene-editing tool, it evolved as a bacterial immune system. When a virus attacks, bacteria capture snippets of the invader’s DNA called “spacers” and use them like molecular “wanted posters” to spot and destroy returning viruses.

However, the array investigated by Dr. Frias-Lopez’s team — previously designated CRISPR array 30.1 — broke this pattern. Its spacers didn’t match any known viruses.

Scientists call such mystery sequences CRISPR “dark matter” or “orphan arrays” because they contain genetic code with no obvious target or known origin. In this case, the team found that the dark matter had a target. It just wasn’t an outside invader. Instead, the spacers matched the bacterium’s own DNA. Why, the researchers wondered, would a germ store a weapon against itself?

To find out, they used gene editing to delete array 30.1. Rather than weakening the bacterium, cutting this genetic brake made P. gingivalis hyperaggressive. Without the array, the germ produced twice as much biofilm, the sticky buildup that forms dental plaque. In tests, the altered strain proved far more lethal, killing half the hosts in 130 hours compared with 200 hours for the normal strain. It also triggered much stronger inflammation in human immune cells.

In a cunning survival strategy, P. gingivalis uses array 30.1 to throttle its own aggression. By keeping it just below the level that triggers a full-scale immune attack, the pathogen stays hidden in the gums, turning what could be a brief battle into a yearslong chronic infection.

Current treatments rely on deep cleaning below the gum line, tissue removal or antibiotics. While effective at reducing bacteria, these blunt approaches kill indiscriminately, harming beneficial microbes and contributing to antibiotic resistance. Frias-Lopez’s findings point to a smarter strategy: Mute the “bad influencer” rather than silencing the entire community.

Future therapies could employ engineered bacteriophages, or viruses that target specific bacteria. Scientists could design these viruses to seek out P. gingivalis and inject a CRISPR instruction that locks the genetic brake in place. This would restore peace to gum tissue without disrupting the mouth’s microbial balance.

The implications of the research reach beyond oral health. Scientists have established clear links between gum disease and serious issues like heart disease and diabetes. Research shows that in more than half of gum disease patients, bacterial toxins leak from inflamed gums into the bloodstream. Once in circulation, these toxins travel to vital organs, triggering inflammation throughout the body.

By keeping P. gingivalis in check, this therapy could do more than save teeth; it could reduce the body-wide inflammation that makes gum disease a silent threat to whole-body health.

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DOI

10.1128/02834-25 

Children with poor oral health more often develop cardiovascular disease as adults

 

Cavities and severe gum disease in childhood are linked to a significantly higher incidence of heart attack, stroke and coronary artery disease in adulthood, according to a new study from the University of Copenhagen

A tooth cavity and bleeding gums is a common scenario among Danish children – and one that researchers now connect to health problems long after the last baby tooth has left the mouth.

Children who have multiple tooth cavities or suffer from severe gingivitis show a markedly higher incidence of stroke, heart attack and coronary artery disease as adults. That’s the conclusion of a new study by researchers at the University of Copenhagen.

The researchers analysed data from 568,000 children born in the 1960s and 70s from the Danish Health Authority’s National Child Odontology Registry and compared them with data on cardiovascular diseases in the National Patient Register up to 2018, when the children had reached adulthood.

By examining these extensive datasets, the researchers identified several striking patterns. Children with numerous tooth cavities had up to a 45% higher incidence of cardiovascular disease in adulthood compared to children with few tooth cavities. For children with severe gingivitis, the incidence was up to 41% higher. The figures vary by sex, but the trend is clear for both groups. At the same time, the incidence seemed to increase as dental problems worsen throughout childhood.

Inflammation is a possible explanation

So, what explains the link between dental disease and cardiovascular disease? The researchers cannot say for certain based on this study, as they did not investigate the causes but merely identified statistical correlations. One theory, however, points to inflammation.

“We suspect that exposure to high levels of inflammation in the form of gum disease and dental caries already in childhood may influence how the body later responds to inflammation,” says Nikoline Nygaard, postdoctoral researcher at the University of Copenhagen’s Department of Odontology and one of the study’s authors.

This theory is supported by several other studies that have found an association between periodontitis and cardiovascular disease. The World Heart Federation has issued a consensus report  stating that strong evidence exists that periodontitis increases the risk of cardiovascular disease. The report suggests that bacteria from gum disease may trigger systemic inflammation elsewhere in the body, accelerating atherosclerosis cardiovascular disease.

In another study, Nygaard and her colleagues also examined the relationship between oral health and type 2 diabetes and found a similar pattern. Children with severe gum disease had up to 87% higher incidence of type 2 diabetes, while those with multiple tooth cavities had 19% higher incidence.

Lifestyle as a key factor

Lifestyle is likely to have a significant impact on the increased incidence of cardiovascular disease and type 2 diabetes, and therefore the researchers adjusted their data for educational level. In general, a higher level of education is associated with healthier and longer lives.

“We cannot rule out that lifestyle plays an important role. But even after adjusting for educational level, the incidence of cardiovascular disease is still quite marked,” says Nikoline Nygaard.

Don’t forget the toothbrush

Although the study cannot establish causality, it may still point to a significant potential for prevention. This is especially relevant given that childhood dental caries is one of the most widespread diseases globally – and both dental caries and gum disease can be prevented relatively easily with thorough tooth brushing.

“In Denmark, 20 per cent of children and young people account for 80 per cent of all registered dental disease. If we can identify markers indicating who is at higher risk of various diseases later in life, we can tailor preventive efforts to those groups. And that could have long-term health benefits well into adulthood,” says Merete Markvart, associate professor at the Department of Odontology at the University of Copenhagen and co-author of the study.

She points out that gingivitis is generally under-researched, despite its high prevalence among children and adolescents. Thus, she would encourage making registration of gingivitis mandatory in the National Child Odontology Register, the same way tooth cavities are registered.

“It’s not that you can solve cardiovascular disease by treating children’s teeth. But if we target our efforts towards specific groups, you can nudge many people in the right direction simply by improving their oral health,” says Merete Markvart.

 

About the study

The researchers used data from the National Child Odontology Register (SCOR) on all children born between 1963 and 1972 who had at least two SCOR registrations – a total of 568,778 individuals. These were compared with National Patient Register data from 1995–2018 on cardiovascular disease, during which time the same individuals were aged between 30 and 56.

The study is a cohort study, in which a well-defined group is followed over time to examine how a particular exposure (in this case, poor oral health) affects the incidence of disease.

The results were adjusted for the participants’ educational level, which had a clear effect on disease incidence. The researchers also adjusted for the occurrence of type 2 diabetes, as this is a known risk factor for cardiovascular disease.

The study only examines correlations between oral health and cardiovascular disease and cannot determine causality – meaning it cannot show whether the dental problems directly caused the cardiovascular diseases or whether other factors played a role.

https://www.sciencedirect.com/science/article/pii/S0167527325011945?via%3Dihub

https://link.springer.com/article/10.1007/s00592-024-02437-4#Sec1

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Journal

International Journal of Cardiology

DOI

10.1016/j.ijcard.2025.134151 

Call for dentists to reduce unnecessary nitrous oxide use

 

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Nitrous oxide used for sedating patients during dental appointments has a significant environmental impact, with wide variation in use and wastage across the UK, according to a new study by UCL (University College London) researchers.

Inhalation sedation uses a dose of nitrous oxide, otherwise known as laughing gas, and is an established technique for managing dental anxiety in children and adults.

It has a wide margin of safety and is used frequently during procedures such as fillings, crowns and root canals. However, nitrous oxide is also a potent greenhouse gas with a global warming potential 273 times greater than carbon dioxide.

Researchers at the UCL Eastman Dental Institute analysed data from 891 episodes of inhalation sedation collected from 31 dental services, covering 128 primary and secondary care sites.

They recorded the average carbon footprint per sedation appointment at 28.6 kilograms of carbon dioxide equivalent (kg CO₂e), equivalent to a 72.8-mile journey in a petrol car*.

At service level, the carbon footprint associated with one week of clinical nitrous oxide use ranged from 38.9 to 1,849 kg CO₂e, highlighting large variations in practice across the country. The figure of 1,849 kg CO₂e would cost the same emissions as 4,709 miles driven in a petrol car*.

The study, published in the British Dental Journal, is the first to quantify the environmental impact of nitrous oxide use in dentistry across different settings in the UK.

First author Alexandra Lyne, from UCL Eastman Dental Institute, said: “Nitrous oxide has an important role to play in dental care, particularly for children and young people, but it is also a powerful greenhouse gas. Our study shows that its environmental impact varies widely between services, largely due to differences in how it is supplied and administered.

“Our recommendations include monitoring use, reducing unnecessary wastage and standardising practice where possible. By doing this, dental services can reduce emissions while maintaining patient care.”

When assessing usage, the study found most participating sites used individual cylinders to supply nitrous oxide, while a smaller proportion used centrally piped systems. Average wastage was 30% higher in sites using piped supplies than in those using cylinders, although variations in wastage were observed across both types of system.

Contributing author Professor Paul Ashley added: "Our analysis showed wide variation in how nitrous oxide is delivered, with flow rates ranging from 1 to 13 litres per minute and no clear link to patient age. This tells us that many patients may be receiving more gas than they actually need. 

"Using higher flow rates doesn’t improve the patient experience or treatment outcomes, but it does increase nitrous oxide use and its environmental impact, so there’s a clear opportunity to deliver care that’s just as effective while being more considered and patient centred."

Despite these variations in use and wastage, inhalation sedation was found to be highly effective across the sites included in the study, with 92% of dental procedures using the technique successfully completed. 83% of patients were children or young people, for whom inhalation sedation is the only standard sedation option available.

Some services reported using inhalation sedation for acclimatisation visits involving simple, non-invasive procedures. These are short frequent visits designed for children to make each dental visit positive and build on the experience by exposing the child to different aspects of treatment at each appointment.

However, the study found no meaningful difference in success rates between services that routinely offered acclimatisation under sedation and those that did not, raising questions about the environmental cost of this practice.

The team of researchers, which also included Sarah Ahmad, concluded that while inhalation sedation has clear benefits, particularly for paediatric patients, dental practitioners should take steps to reduce the environmental impact of nitrous oxide use.

They recommend auditing gas use and wastage, minimising flow rates and duration of administration, reviewing the routine use of sedation for acclimatisation, and considering alternatives where appropriate.

They also call for professional bodies to take account of the environmental impact of nitrous oxide in future dental sedation guidelines, and for further research into wastage and clinical administration of dental nitrous oxide use to be conducted.

* Figures taken from the Environmental Protection Agency website

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DOI

10.1038/s41415-025-9201-6 

What Zinc concentration in teeth reveals

 

X-ray methods reveal strong gradients on the Zinc distribution in teeth – these insights could inspire dental medicine

Peer-Reviewed Publication

Helmholtz-Zentrum Berlin für Materialien und Energie

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image: 

Left: Micro-computer tomography of a complete tooth; the cross-section next to it shows internal structures. Top right: Micro-CT section of the same volume shows absorption. Below are intensity distributions of fluorescence measurements of phosphorus, calcium and zinc. While the main components calcium and phosphorus are distributed homogeneously, the zinc concentration increases towards the pulp.

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Credit: © View (2026). Doi: 10.1002/VIW.20250173

Teeth are composites of mineral and protein, with a bulk of bony dentin that is highly porous. This structure is allows teeth to be both strong and sensitive. Besides calcium and phosphate, teeth contain trace elements such as zinc. Using complementary microscopy imaging techniques, a team from Charité Berlin, TU Berlin and HZB has quantified the distribution of natural zinc along and across teeth in 3 dimensions. The team found that, as porosity in dentine increases towards the pulp, zinc concentration increases 5~10 fold. These results help to understand the influence of widely-used zinc-containing biomaterials (e.g. filling) and could inspire improvements in dental medicine.

Teeth have a complex structure: The dental pulp with the nerves is surrounded by dentine, a porous bony material, covered externally by enamel in the mouth and cementum in the roots. Although dentine is criss-crossed by countless micrometre-sized dentine tubules, teeth can withstand decades of cyclic, repeated forces. The density of the dentinal tubules increases towards the pulp, meaning that the dentine becomes increasingly porous towards the inside. Dentine tubules conduct stimuli to the nerves and enable cold and hot sensations, via connection to cells located in the pulp and root canals. Similar to bone, dentine contains mostly calcium and phosphate (in nanocrystals) as well as organics and a range of trace elements that are normally homogeneously. But the trace element zinc is almost non-existent in some regions, yet quite prevalent near the pulp Up to this study, it was not known what the concentration of natural Zinc is, and how it is distributed in healthy teeth.

Ideal teeth

The team, led by Prof. Dr. Paul Zaslansky, Charité Berlin, and Dr. Ioanna Mantouvalou, HZB set out to solve this question, only to realise that discarded human teeth are usually contaminated with zinc from treatment or toothpaste. They therefore made use of cattle teeth, widely discarded from slaughterhouses. These show e.g. through infrared studies performed with the IRIS team of BESSY II a high similarity to human teeth, being only much younger and without histories of dental treatment or toothbrushing.

Where is zinc?

‘First, we made fine cuts and examined them under a scanning electron microscope. These images revealed that the material between the individual tubules is almost perfectly homogeneous,’ says HZB SyncLab responsible Mantouvalou. The team then examined the teeth using different dental and industrial 3D X-ray tomography systems to map their three-dimensional microstructure, in particular density. As expected, tooth density decreases near the pulp, corresponding to an increase in tubules. These findings made it possible to model the material correctly and evaluate the experimental data from maps of micro-X-ray fluorescence spectroscopy. ‘We recorded the signals from many elements, in particular calcium, phosphorus and zinc. While calcium and phosphorus, both of which originate from the nanocrystals of dentine, are distributed evenly, we observed and quantified a very sharp increase in the zinc concentration from the outside to the inside, i.e. towards the pulp,’ says Mantouvalou.

Useful insights

‘These results are very helpful for the further improvement of dental care, for example whether the dentist should recommend low or high zinc containing materials during treatment,’ explains Zaslansky. In healthy teeth, zinc is enclosed in the dentine. However, contact with acids, whether through caries or through root canal treatment with zinc-containing pastes, could potentially chemically activate enzymes, with possible negative effects. ‘Studies on human teeth are needed to confirm our bovine-tooth based hypothesis’.  

Zinc as an indicator

Another important point: The study shows that Zinc could serve as a good proxy to determining bony-material mineral density. ’Bone density is a huge concern for many patients: everyone knows that we want calcium and more mineral for bones to be strong. But actually, maybe what we want is a good balance of micro porosity?’ suggests Zaslansky and concludes : ‘We find unexpectedly that Zinc can likely be used as a very sensitive measure of gradients in material density, which may change over the lifetime. Density is linked to mechanical competence of bony tissues, and should neither be too high or too low, to serve in the human body. With high sensitivity methods such as X-ray fluorescence, we may be able to take samples and monitor density changes with ageing, for example due to use of well-chosen dental fillings or oral pastes.’

 

Note:

The collaboration took place as part of the DFG-funded programme ‘FOR 2804: Materials Science of Teeth in Function’

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Journal

View

DOI

10.1002/VIW.20250173 

Underbite is associated with tooth loss risk

Crooked teeth or a misaligned bite can cause a whole host of problems, including speech issues and/or difficulty eating or properly cleaning teeth. What many don’t consider, however, is how a bad bite or crowded teeth can affect the health of other teeth in the mouth.
 
Malocclusions, or misaligned bites, refers to a condition in which the upper and lower teeth do not align properly when the mouth is closed. It can arise from a variety of factors, including tooth position and jaw relationships.

Previous studies have established associations between specific malocclusions and tooth loss. Two malocclusions in particular—crossbite and open bite—can change the way force is distributed to other teeth in the mouth when chewing food, which could influence the risk of tooth loss. To examine whether anterior crossbite or open bite are associated with tooth loss-related outcomes in adults aged 40 years and older, a group of researchers from Tohoku University designed an observational study.
 
The team published the study on January 8 in the journal Clinical Oral Investigations.
 
The research team compiled data from 17,349 adults aged 40 years and older from the Tohoku Medical Megabank Project Community-Based Cohort Study and categorized them into four groups—normal occlusion, anterior open bite, anterior crossbite and combined malocclusion—based on oral measurements. The team then determined whether patients had  ≤19 remaining teeth and posterior (back of the mouth) tooth loss to assess the potential effects of anterior crossbite and open bite compared to a normal bite.
 
"Using one of the largest general population-based datasets, this study shows that anterior crossbite is associated with a higher prevalence of tooth loss in adults. Having fewer than 20 teeth affects chewing, nutrition, frailty, and healthy life expectancy; therefore, identifying this risk is important for public health. Our findings suggest that bite alignment, in addition to cavities and gum disease, may be related to long-term tooth retention. This highlights the importance of regular dental checkups and appropriate orthodontic evaluations,” said Kento Numazaki, assistant professor in the Division of Orthodontics and Dentofacial Orthopedics at Tohoku University Graduate School of Dentistry and first author of the research paper.

Specifically, the study found that adults with an anterior crossbite (but not anterior open bite) exhibited a higher likelihood of tooth loss and a 1.14-fold higher risk of losing molars after adjusting for age, sex, oral hygiene, caries, periodontal disease and lifestyle factors. Further age-stratified analyses showed that differences in molar retention between occlusal groups were more pronounced in older age groups.
 
In contrast, adults with an anterior open bite had a lower prevalence of posterior tooth loss in the study, suggesting that different anterior malocclusions may influence tooth retention in distinct ways.
 
The study leveraged one of the largest general population-based cohorts (the Community-Based Cohort Study and Three-Generation Cohort Study)  and provides the first clear population-level evidence linking anterior crossbite to tooth loss. Armed with these initial findings, the research team plans to further investigate the effects of anterior crossbite on tooth loss and oral health beyond Japan.
 
“The next step will be to conduct longitudinal studies to better understand how tooth loss progresses over time in individuals with anterior crossbite,” said Numazaki. “In the longer term, we hope to explore whether the associations observed in Japan are also seen in other populations, potentially through future international collaborations.”

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Journal

Clinical Oral Investigations

DOI

10.1007/s00784-025-06715-5 

Toothbrush-activated powder whitens, repairs and protects teeth

 

Even with regular brushing, teeth can become stained from genetic factors or consuming foods and drinks like tomatoes and coffee. Chemical whiteners can help, but they can also damage teeth in the process. So, researchers reporting in ACS Nano have designed a prototype teeth-whitening powder that is activated by the vibrations from an electric toothbrush. The system both brightened and protected teeth in lab demonstrations.

“This work offers a safe, at-home teeth whitening strategy integrating whitening, enamel repair and microbiome balance for long-term oral health,” says Min Xing, first author on the study.

Peroxide-based bleaching with strips, gels and mouth rinses is a popular option among consumers for whitening stained teeth. This type of chemical whitening generates reactive oxygen species (ROS), compounds that break apart stain-causing molecules. But in addition to removing stains, many whitening techniques can damage the tooth enamel, which might result in easier re-staining or other oral problems. Now, Xing, Wenhao Qian, Xuanyong Liu, Jiajun Qiu and colleagues are developing a tooth-whitening compound that generates ROS when activated by electric toothbrush vibrations while strengthening and repairing teeth at the same time.

The researchers combined strontium and calcium ions with barium titanate in a solution and then heated and formed it into a ceramic powder, dubbed BSCT. When vibrated, the powder generates a small electric field — a phenomenon known as the piezoelectric effect — that causes ROS-generating chemical reactions.

In initial lab tests using human teeth artificially stained with tea and coffee, four hours of brushing with BSCT and an electric toothbrush caused visible whitening. After 12 hours of brushing, treated teeth were almost 50% whiter than the control group stained in the same way but brushed with saline. For teeth with damaged enamel and dentin, BSCT brushing regenerated these structural components because the strontium, calcium and barium ions included in the powder formed deposits on the tooth surface.

Next, researchers tested the powder on rats fed high-sugar diets. Daily brushing for one minute over four weeks using BSCT helped restore the rats’ oral microbiome, killing periodontitis-causing Porphyromonas gingivalis and Staphylococcus aureus bacteria and reducing inflammation.

Though current tests haven’t yet incorporated the BSCT powder into a toothpaste formula, researchers say that this study is a step toward a new effective, at-home treatment for safely whitening teeth and promoting oral health.

The authors acknowledge funding from the Youth Innovation Promotion Association of the Chinese Academy of Sciences, the Science and Technology Commission of Shanghai Municipality, the Shanghai Medical Key Specialty, the Medical Key Subject of Xuhui District, and the Opening Project of the State Key Laboratory of High Performance Ceramics.

Mechanisms by which smoking worsens periodontitis discovered

 

Smoking tobacco is known to worsen symptoms of periodontitis and reduce responsiveness to treatment. Using high-resolution spatial transcriptomics, researchers identified differences between smokers and non-smokers in the expression of genes that weaken gum epithelial integrity and cause bone damage through inflammation. They also identified CXCL12 secreted by endothelial cells in gums as a crucial mediator of immune-cell recruitment that drives excessive inflammation. CXCL12 is a possible target for new therapies against periodontitis aggravated by smoking.

Healthy gums, or periodontal tissue, are a key to good oral health. Gums provide crucial nutritional, immunological and mechanical support to the teeth and jaws. Unfortunately, millions of people suffer from severe chronic inflammation of the gums, a condition called periodontitis. Periodontitis occurs when the immune system responds abnormally to microbes entering the gum tissue. Over time, periodontitis causes gums to recede, bones surrounding the mouth to weaken, and may even lead to the loss of teeth.

Previous research has shown that tobacco smokers are not only more likely to develop periodontitis, but the disease also progresses faster, shows more severe symptoms, and responds poorly to treatment compared with non-smokers. These differences have been linked to smoking-related alterations in:

• the gum’s epithelial barrier,
• fibroblast function and epithelial–fibroblast communication, and
• immune and inflammatory responses within periodontal tissue.

Yet, the precise cellular mechanisms have remained unclear due to limitations in available research technologies.

A team of researchers from Sun Yat-sen University, China, led by Professor Chuanjiang Zhao, have used high resolution Visium HD single-cell spatial transcriptomics to analyze the different molecular pathways activated in smokers and non-smokers with periodontitis. Their findings have been published in Volume 17 of the International Journal of Oral Science on August 01, 2025.

“Understanding the complex cellular interactions that contribute to disease progression in smoking-associated periodontitis is important,” remarked Prof. Zhao regarding the importance of this study. He added, “By employing the Visium HD platform, we aimed to map the spatial distribution of different cell types within healthy and diseased periodontal tissues and identify smoking-induced changes in gene expression patterns across various cell populations.”

To explore how smoking affects epithelial cells, the team first examined cells exposed to bacterial lipopolysaccharide (LPS) alone versus LPS plus nicotine. The combination triggered larger changes in genes related to epithelial structure, barrier integrity, communication, and inflammation—suggesting that smoking weakens the epithelial barrier and heightens inflammatory susceptibility.

The researchers then compared gene expression across multiple cell types in tissue samples from healthy gums (HG), non-smokers with periodontitis (P), and smokers with periodontitis (SP).

Describing differences in fibroblasts, cells that maintain gum structure and integrity, Prof. Zhao says, “Our results revealed that individuals in the smoking group, as opposed to healthy controls, presented upregulated expression of genes linked to ageing, intrinsic apoptotic signalling, and mitotic processes.” SP fibroblasts also showed elevated expression of genes associated with inflammation and immune cell recruitment, helping explain the more pronounced tissue damage in smokers.

Spatial transcriptomic analysis further revealed that endothelial cells and macrophages were positioned in close proximity only in smoking-associated periodontitis, enabling stronger inflammatory interactions. SP tissues also contained a higher proportion of pro-inflammatory macrophages, which played a central role in driving periodontal destruction.

Interestingly, this recruitment and activation of macrophages seemed to depend on one molecule –C-X-C motif chemokine 12 or CXCL12. In the presence of CXCL12 secreted by endothelial cells, macrophages turned pro-inflammatory. Suppressing CXCL12 secretion made the macrophages anti-inflammatory. As further confirmation of these findings, the team found that CXCL12 suppression reduced inflammation and bone damage in mice with periodontitis aggravated by nicotine.

“Targeting CXCL12 shows promise in mitigating inflammation and bone resorption in individuals with smoking-induced periodontitis,” says Prof. Zhao, describing a potential new therapeutic approach.  He concludes, “Future research should investigate local delivery systems, like nanoparticles or liposomes, to reduce systemic side effects and improve treatment precision.”

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