Understanding our teeth
Our teeth do more than just help us chew - they’re a key part of how we speak, smile, and express ourselves. But behind every tooth is a complex structure and a delicate balance of biology and care. Our everyday oral care products play a vital role in keeping our mouths healthy and fresh.
The science behind our teeth
Our teeth are made up of layers. The outer layer, enamel, is a hard, calcium-based mineral (hydroxyapatite) and the hardest substance in the human body, essential for decades of chewing. Beneath this is dentine, a living tissue with nerve endings, making it sensitive to hot and cold. At the centre lies the pulp cavity, which houses nerves and blood vessels that keep the tooth alive and healthy.
The main threats to our oral health come from diet and naturally occurring bacteria in the mouth. Oral care products are designed to remove food debris and plaque, strengthen enamel, and freshen breath.
Plaque, tartar and gum disease
Plaque is a sticky film of bacteria that builds up if teeth aren’t brushed regularly, leading to tooth decay and gum disease. If left untreated, plaque can harden into tartar (also known as calculus), which cannot be removed by brushing and requires professional cleaning.
Gingivitis, an early form of gum disease, causes gum inflammation and can usually be reversed with good oral care. If it progresses to periodontitis, the deeper tissues and bone around the tooth are affected, which can eventually lead to tooth loss.
Tooth decay
Tooth decay happens when plaque bacteria feed on sugars and produce acids that weaken and dissolve enamel - a process called demineralisation. With time and the help of saliva and fluoride in toothpaste, the enamel can repair itself (known as remineralisation). However, frequent sugar intake or poor brushing means the tooth can’t recover, leading to cavities.
Sensitive teeth
Sensitivity to hot, cold, sweet, or acidic foods can occur when enamel wears away, exposing the softer dentine beneath. This may be caused by receding gums, over-brushing, acid erosion, or tooth damage. Special toothpastes for sensitive teeth can help by blocking nerve pathways or soothing nerves. In more severe cases, dentists may recommend treatments like fluoride gels, sealants, or root canal therapy.
Bad breath
Bad breath (halitosis) can be caused by strong foods, alcohol, smoking, dry mouth, or poor oral hygiene. Saliva plays a key role in washing away bacteria, so dehydration or mouth breathing can worsen the issue. Persistent bad breath may be a sign of a medical condition and should be checked by a dentist.
Fluoride
Found naturally in some foods such as tea, fish, vegetables and fruit juices, fluoride's inclusion into toothpaste, which became widespread in the 1960s, has been a major public health advance.
Fluoride has been the major factor in reducing the incidence of dental decay and has been used in toothpastes for over 50 years. Further information about the strong evidence for fluoride preventing dental caries (tooth decay) may be found at the UK Government website.
How fluoride works
It works in several important ways. Fluoride promotes a chemical reaction in tooth enamel that draws in replacement minerals including calcium. This promotes tooth remineralisation. In addition, fluoride can also incorporate itself into enamel weakened by acid attack, creating an enamel mineral which is more resistant to future acid attacks than regular tooth minerals. Fluoride also reduces the amount of acid that plaque bacteria can produce, which is helpful because an acidic environment promotes demineralisation of tooth enamel.
How does toothpaste work?
Toothpaste is designed to protect against oral health problems in a few important ways. Most toothpastes contain mild abrasives that gently scrub away plaque and food debris without damaging the enamel. This physical cleaning is essential for maintaining a healthy mouth. Many toothpastes also include fluoride, a mineral that has made a huge difference to public dental health.
Fluoride works by helping to repair enamel that has been weakened by acid. It encourages the reabsorption of minerals, like calcium, back into the enamel structure. Once absorbed, fluoride strengthens the enamel and makes it more resistant to future acid attacks. This process of remineralisation is what helps to prevent tooth decay over time.
In addition to fluoride and abrasives, toothpaste contains a carefully balanced mix of ingredients to make it both effective and pleasant to use. A small amount of detergent is usually added to help create foam, which spreads the toothpaste around the mouth and lifts away food particles. One of the most common detergents used is sodium lauryl sulphate. To keep the toothpaste smooth and moist, manufacturers include humectants, like glycerin, and thickeners, such as cellulose gum, which give the paste its familiar texture and help it stay on the toothbrush.
To ensure the toothpaste stays fresh and safe to use, preservatives are included to prevent the growth of bacteria. Finally, flavourings and colourings are added to improve the taste and appearance of the product - because if toothpaste didn’t taste good or look appealing, we’d be less likely to use it regularly.
Toothpaste may seem simple, but it's the result of years of scientific development to help protect our teeth, freshen our breath, and keep our mouths feeling clean and healthy. Brushing twice a day with a fluoride toothpaste is one of the most effective ways to care for your teeth and gums.
How does mouthwash work?
Mouthwash helps keep your mouth clean by rinsing away leftover food particles and germs from your teeth, gums, and tongue. When used alongside brushing and flossing, mouthwash can be a useful tool to help maintain a clean, fresh, and healthy mouth.
Most mouthwashes include a few common components. They contain cleaning agents that help remove food and loose plaque, along with flavourings to improve the taste and leave your breath feeling fresh. Many also include antimicrobial agents, such as alcohol or alcohol-free alternatives, to kill germs that cause bad breath and tooth decay.
To keep the liquid stable and effective, preservatives are added to prevent bacterial growth, and water is used to dissolve and blend the ingredients. Some mouthwashes may also contain fluoride, which helps strengthen tooth enamel and protect against acid attacks.
How do teeth whitening products work?
Teeth whitening products work in different ways depending on the type of product. Whether it’s a toothpaste, a home-use kit, or a treatment using light technology, the goal is the same: to remove surface stains and brighten the appearance of teeth.
Whitening toothpastes
Most whitening toothpastes work through gentle abrasion. They contain tiny polishing particles - such as aluminium oxide, hydrated silica, dicalcium phosphate, or calcium carbonate - that help scrub away surface stains from food, drink, and smoking. When used with a toothbrush, the mild abrasive action helps clean the enamel surface, making teeth appear whiter. Some toothpastes marketed for smokers are more abrasive than regular formulas.
A few whitening toothpastes may also include low levels of peroxide compounds, but these are present in such small amounts that their bleaching effect is limited.
Home whitening kits
At-home whitening kits typically use hydrogen peroxide gel, applied to the teeth using strips or custom trays. These products are worn for a few hours each day over a period of up to two weeks. The peroxide acts as an oxidising agent, penetrating the enamel and breaking down the molecules that cause stains.
However, under current UK and EU regulations, over-the-counter whitening kits are only permitted to contain up to 0.1% hydrogen peroxide, which means the whitening effect is very gradual and less intense than professional treatments.
Teeth whitening innovations
Because peroxide levels in consumer products are strictly regulated in the UK and Europe, manufacturers are exploring alternative technologies. One emerging method is light-activated whitening, where specific types of light are used to enhance the whitening effect of bleaching agents.
Whitening products can help improve the appearance of teeth, but they are most effective when used alongside regular brushing, good oral hygiene, and routine dental care. If you're considering whitening your teeth, it's always a good idea to speak with your dentist first.
