What is tooth decay?
Tooth decay is one of the most common diseases in the world, affecting millions of people every year and can strike anyone, from children to adults. It is a multifactorial infectious disease that progressively damages the tooth's hard tissues—enamel and dentin—until it reaches the dental pulp if not treated promptly.
Cavities begin when bacteria in dental plaque metabolize sugars, producing acids that lower the pH of the mouth (below 5.5) and cause demineralization of the enamel. Over time, this process creates a cavity: a decayed tooth .
In Italy, according to data from the Ministry of Health , over 60% of adults have active or treated tooth decay, while childhood tooth decay remains one of the main chronic diseases in school-age children.
Which teeth are most affected?
The teeth most vulnerable to decay are the molars and premolars , especially the upper ones. Their irregular surfaces encourage the accumulation of food debris and bacteria in the grooves, making it more difficult to remove plaque with a traditional toothbrush.
Interdental cavities are common between the front teeth, while cervical caries — which develops near the gum — is more common in adults and the elderly, often in the presence of gingival recession .
The various stages of tooth decay
The caries process is progressive and can be divided into several phases:
1. Initial caries
It appears as a whitish or chalky spot on the enamel, a sign of demineralization. At this stage, the decay is still reversible with remineralizing treatments using fluoride or hydroxyapatite.
2. Superficial caries
The acids begin to erode the enamel, creating a small cavity. Symptoms are mild or absent, but progression is ongoing.
3. Deep caries
The infection reaches the dentin , the layer beneath the enamel, which is much softer and more sensitive. At this point, pain or discomfort may occur when chewing and eating hot or cold foods.
4. Penetrating caries
The lesion reaches the dental pulp , where blood vessels and nerve endings are located. Throbbing pain occurs, and if left untreated, pulpitis may develop.
5. Perforating caries and abscess
The infection spreads to the root, causing a dental abscess and, in severe cases, tooth loss.
Causes of tooth decay
The formation of dental caries is the result of an altered balance between protective factors (such as saliva and oral hygiene) and risk factors.
Main risk factors
- Plaque: A biofilm of bacteria and food debris that, if not removed regularly, hardens into tartar.
- High-sugar diet: Sweet or acidic foods and drinks (soft drinks, energy drinks, juices) promote acid production.
- Poor oral hygiene: Insufficient hygiene allows bacteria to proliferate undisturbed.
- Reduced salivation: Saliva neutralizes acids and remineralizes teeth; medications, stress, or dehydration can reduce it.
- Smoking and alcohol: alter the oral pH and compromise gum health.
Symptoms of tooth decay: how to recognize it
In the early stages, tooth decay is often asymptomatic. As it progresses, the following may appear:
- dark or white spots on the enamel;
- dentinal hypersensitivity to heat, cold or sugars;
- localized pain during chewing;
- persistent bad breath;
- swollen gums or abscesses in advanced cases.
A decayed tooth doesn't heal on its own: dental tissue doesn't regenerate. Only timely dental intervention can halt the progression and save the tooth.
Diagnosis and treatments
The dentist can detect a cavity by:
- visual inspection and survey with specific tools;
- bite-wing radiographs to detect interdental or deep cavities;
- advanced techniques such as transillumination or the use of AI in early diagnosis.
Possible treatments
- Fluoride treatment: strengthens enamel in early cavities.
- Filling: removal of decayed tissue and reconstruction with composite materials.
- Dental inlay or crown: for extensively damaged teeth.
- Root canal treatment: if the decay has reached the dental pulp.
- Extraction and implant: in extreme cases, when the tooth is no longer salvageable.
How to prevent tooth decay
1. Daily oral hygiene
Brush your teeth at least twice a day for 2 minutes with a quality toothbrush and a toothpaste containing fluoride or biomimetic hydroxyapatite , which helps strengthen enamel. Use dental floss or interdental brushes to remove food debris from between your teeth.
2. Balanced diet
Limit simple sugars, carbonated drinks, and ultra-processed foods. Incorporate foods rich in calcium, phosphorus, and magnesium (such as legumes, green leafy vegetables, fish, and dairy products) into your diet.
3. Constant hydration
Drinking plenty of water helps maintain saliva flow and neutralize acidity in the mouth.
4. Regular check-ups
Visit your dentist every 6–12 months and have a professional cleaning twice a year. In Italy, it's recommended to consult your trusted dentist or a specialized oral hygiene center.
5. Dental sealants (in children)
Sealants placed on permanent molars prevent plaque buildup in the grooves and reduce the risk of childhood tooth decay by up to 70%.
Prevention and technology: a new approach
Today, tooth decay prevention is also supported by technology. Devices like CleanOS were designed specifically to reduce human error in daily cleaning, thanks to customized heads that uniformly cover every tooth surface, removing plaque and debris from deep within.
Effective and consistent oral hygiene, combined with regular check-ups, is the best way to maintain a healthy smile over time and prevent complications such as gingivitis or periodontitis.
Conclusion
Tooth decay is a common yet preventable disease. A mindful approach based on daily hygiene, a balanced diet, and regular checkups can avoid invasive treatments and ensure a healthy smile over the long term.
