I’m sure we’ve all come across those advertisements displaying tooth sensitivity and aches and proceeding to recommend x-branded toothpaste to soothe and dull the pain and reaction when your tooth comes in contact with extreme temperatures. Irreversible pulpitis is a dental condition, that leaves your tooth in im-pulp-sible pain!

This article provides a deep dive into irreversible pulpitis, with an exploration of its pathogenesis, aetiology, approaches towards differentially diagnosing it, and management strategies. 

Introduction

The structural composition of a tooth is as follows:

• The enamel is the outermost protective layer
• The dentin is the middle layer
• The pulp in the tooth is the innermost 

The pulp contains various specialised cells, nerve endings, connective tissues, and blood vessels; all of which help provide nutrition and sensation within the tooth, as well as maintain its vitality and health.¹ 

Inflammation in the pulp tissue occurs as a result of recent injury or trauma, defective restorations, or the development of caries. This could lead to the formation of pulpitis, which can be classified as reversible or irreversible.² This condition often causes severe toothache and sensitivity. The patient is unable to handle extreme temperatures, - that call for dental intervention in most instances.

What is pulpitis?

A dental condition characterised by the dental pulp present in the teeth getting inflamed. Pulpitis can be classified as reversible and irreversible.³ 

• Reversible: mild to moderate inflammation in the dental pulp, present in the tooth, can be treated with appropriate dental treatment. This can be due to caries or an exposed dentin
• Irreversible: increased inflammation that seems to progress without any signs of healing, present deep within the pulp of the tooth. Often caused as a result of a deep infestation of caries, rendering the pulp unsalvageable 

How are caries formed?

At times, usually after waking up after a long night of slumber, if you run your tongue or finger across your teeth. You tend to notice a sort of grainy film coating on the surface of your teeth. You then, not pleased, rush to brush your teeth to clean this layer off it. This layer of film is dental plaque, which forms through a natural process occurring as a reaction between acids, carbohydrates, and bacteria present in the mouth microbiota.⁴

Formed as a result of the bacteria, they lead to the formation of caries. When the bacteria are present, they release acids that tend to accelerate tooth decay and thereby cause the occurrence of caries. Caries, colloquially known as cavities, is the decay of the tooth. Rudimentarily caused by the Streptococcus mutans bacteria, which are tooth-adherent. The bacteria tend to demineralize the structure of the tooth producing acid by metabolising their sugars, changing the pH of the region.⁵ This loss of minerals upon the surface can be tedious and slow, making the changes invisible at times until it is too late. 

Once this bacteria invades the layers of the tooth and reaches the innermost region that is pulp. The contact with the contents present tends to provoke an immune response within the teeth, which in turn results in an immune response, finally causing tissue damage. 

Causes of irreversible pulpitis

Although the occurrence of bacterial infection is one of the most common causes of irreversible pulpitis, other factors can also increase the chances of its development. Such as:³

• Trauma to the tooth
• Preparations of the crown
• Constant procedures that repeatedly invade the tooth 
• Development of deep cavities closer to the pulp
• Constant clenching and grinding together of the teeth
• A crack in the tooth

These can lead to an infection due to the ease of exposure to foreign substances through the rupturing of the enamel of the teeth, which can lead to bacterial entrance. 

The body’s way of combating any unrecognised substance or foreign body is via generating an immune response to defuse the prevalence of the disease-causing substance. The immune response tends to lead to inflammation at the site of infection, thereby exacerbating feelings of discomfort and pain. As well as causing an increase in pressure and higher tooth sensitivity. 

How do you know if it is irreversible pulpitis?

Due to severe damage to the tooth in the case of irreversible pulpitis, the individual would experience constant, intense pain that tends to be harder to localise and determine the exact origin of.

The consumption of foods causing pain at extreme temperatures that goes away after a short period is classified as reversible pulpitis and can be resolved via a quick dental appointment.⁶  

Symptoms of irreversible pulpitis

• Lingering (>30 seconds), and intense pain from temperature changes
• Spontaneous and sharp pains
• Enhance pain by change in posture and percussions in teeth
• Clinical presence of deep caries in and on the tooth. 
• Tingling and swelling of gums

Although not present with plenty of symptoms, the presence of prolonged and persistent pains that tend to linger or occur spontaneously due to postural changes followed by the onset of caries on the teeth can point towards the occurrence of irreversible pulpitis.⁶ 

Diagnosis of irreversible pulpitis

When diagnosing irreversible pulpitis, it is usually examined by a dentist or endodontist. The individual would undergo:^2,3,6 

• Comprehensive assessment of the patient’s dental history and hygiene habits
• Clinical examination to detect teeth
• Percussion
• Thermal sensitivity 
• Palpitations
• Radiographic images (such as dental X-rays, bitewing or periapical radiographs)

These characteristics enable the professional to obtain a thorough, detailed examination of the patient’s clinical history. The identifying causative lesion or caries can be targeted, by noticing the pathological changes in the periapical or any new changes in the pulp of the afflicted individual. 

Treatment for irreversible pulpitis 

The pulp tissue within the tooth affected by irreversible pulpitis tends to die due to constant inflammation. This is due to the pulp not being able to heal itself anymore and the inflammation being present even after constant brushing. The main aim of irreversible pulpitis is to eradicate the source of infection that is causing inflammation whilst trying to preserve as much of the tooth as humanly possible. Currently, available treatment options consist of:^2,3,6 

Root canal therapy

When solely the pulp in its entirety gets inflamed due to bacteria, a root canal is opted for. The pulp tissue as a whole is removed and replaced with a biocompatible material that is then sealed off at the top of the tooth to prohibit reinfection with the bacteria that causes caries. This process is time-consuming and the individual undergoes numerous visits to finish filling their entire hollowed-out tooth. 

Tooth extraction

In instances where the tooth has completely been engulfed via the bacteria forming caries and is irreversibly damaged. Endodontic (root canal) therapy is ineffectual and a complete tooth extraction is conducted to remove the source of pain and prevent the bacteria from spreading to the surrounding environment within the patient’s mouth.

Pulpotomy

When the bacterial infection is irreversible, implying that it has penetrated through the enamel of the tooth, but is restricted only to the top coronal part of the pulp, a pulpotomy is performed. This is when only a portion of the pulp within the tooth is drained to preserve the rest and eradicate the infectious bacteria present, reducing pain and infection.

Antibiotic therapy 

When infection is acute and not widespread into the pulp of the tooth, antibiotics can be prescribed to tame and rid the tooth of the microbial infection. This causes a reduction in inflammation and healing of the tooth, including its pulp. Usually prescribed in conjunction with endodontic therapy. 

Prevention of irreversible pulpitis

Several practices can be done. These include:³ 

• Switching to fluoride toothpastes that aid in protecting the enamel of the tooth
• Going to the dentist for routine teeth checkups
• Reducing consumption of sodas and candy to reduce the chances of teeth becoming a breeding environment for S.mutans bacteria
• Following a good oral care routine, brushing your teeth thoroughly to avoid any spread of bacteria due to leftover food between teeth
• Wearing a mouthguard in the case of excessive teeth grinding to reduce chances of damage to the enable or any cracks or breaks

Summary

Irreversible pulpitis is a common dental condition characterised by unresolvable toothache due to damage to the pulp present in the tooth. Usually present with symptoms like spontaneous aches due to postural changes, and lingering pains that remain even after 30 seconds of removing any extreme temperatures. The development of caries, resulting from the formation of dental plaque is a crucial diagnostic factor when it comes to irreversible pulpitis. Resolving this condition with proper dental hygiene and visiting your dentist or endodontist routinely for checkups can help with the prevention and reduction of this condition.