What Do Dentists Use to Numb Your Mouth? Dental Anesthesia Explained

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Dentists use dental local anaesthesia to numb the mouth during procedures. Lidocaine is the most common anaesthetic.

What Do Dentists Use to Numb Your Mouth? Local Anesthesia Explained

This article will go over the topic of dental anaesthesia along with the numerous numbing agents and techniques that dentists use. 

Common fears and misconceptions about dental anaesthesia

Fear among patients is common concerning painful injections during treatment or a previous bad experience with dental anaesthesia due to a burning sensation, lack of numbing gel, or dentist’s inexperience. Skilled dentists can alleviate discomfort with numbing gels.

Types of Dental Anaesthesia

Types of anaesthesia used in dentistry include local anaesthesia, General anaesthesia and Sedation. Local anaesthesia is used when the patient is awake and responsive but feels no pain in the specific area being treated.

Nitrous oxide reduces pain and has an anti-anxiety and sedative effect. Twilight sleep involves strong painkillers and sedatives administered either in pill form or intravenously, usually through a vein in the arm.

Local vs General Anaesthesia, which is the right option for you?

Local anaesthesia is a safer alternative to general anaesthesia due to its localized loss of sensation and reduced pain stimuli, bypassing systemic effects like loss of consciousness and hemodynamic alterations. Patients may still experience movement or pressure.

Patients with disabilities often face challenges in accessing dental services and tolerating treatment, requiring sedation or general anaesthesia.

Sedation is a safe alternative, but severe cooperation problems can make it difficult. Clinicians may prefer comprehensive treatment under general anaesthesia for safety and efficacy, despite potential risks. 

Local Anaesthesia in Dentistry

Dental anaesthesia is medication to numb sensations during dental procedures, primarily to manage and relieve pain.

Local Anaesthesia in Dentistry

Depending on the procedure’s complexity and the patient’s comfort and health condition, it can range from simple local injections to complex general anaesthesia.

The goal is to make dental procedures painless and more comfortable for patients.

How does local anaesthesia work to numb the mouth?

Teeth are supplied by nerves, causing sensations like heat, cold, pressure, vibration, and pain. Pain messages are transmitted through electrical signals that travel through these nerves, which can be blocked by chemicals.

A dental needle is placed near the nerves, and local anaesthetic (LA) is injected into the affected area, interrupting their ability to transmit pain messages.

What are the most commonly used local anaesthetic agents?

Lidocaine is the most common anaesthetic. Local anaesthetics are divided into two classes: amides and esters. Amide anaesthetics are common in dentistry, including lidocaine, prilocaine, mepivacaine, and bupivacaine. Modern anesthetics, named after “cain,” are less likely to cause allergic reactions and are a fraction of the anesthetics injected into the mouth.

General Anesthesia

General anaesthesia is an artificially induced deep sleep that removes conscious awareness of dental surgery and pain. It is administered (intravenously) through an IV in the vein. 

When is General anaesthesia used in dentistry?

General anaesthesia is often used for dental restorations, especially for patients with dental fear, strong gag reflex, or dental fear due to past traumatic experiences.

Patients with severe gag reflex may require general anaesthesia as all strategies are unsuccessful, and dental treatment may not be possible.

General Anaesthesia in Dentistry

Major dental restorations, such as wisdom teeth extraction, dental implants, and long restorations, are often performed under general anaesthesia

Risks and benefits of general anaesthesia for dental procedures

Sedation and general anaesthesia medications can cause side effects like nausea, headache, shivering, hallucinations, slurred speech, pain, dizziness, tiredness, and lockjaw due to surgery trauma.

Special considerations for patients receiving general anesthesia

Before surgery, your doctor will discuss your medical conditions, medications, allergies, smoking, alcohol, and past anaesthesia reactions with you. It is strictly advised not to eat or drink anything but water for 8 hours before surgery and may need to stop certain medications a week or more before the surgery to prevent bleeding.

Techniques for Administering Dental Anesthesia

Topical Anesthesia

The topical anaesthetics applied to the soft tissues in the oral cavity are useful in easing the pain associated with the infiltration of local anaesthetics.

Different forms of topical anesthesia 

Topical anaesthetics come as solutions, creams, gels, and sprays. They contain lidocaine or benzocaine as active ingredients.

Topical anaesthetics act on the peripheral nerves and reduce the sensation of pain at the site of application. In dentistry, topical anaesthetics are used to control local pain caused by needling, placement of orthodontic bands, the vomiting reflex, oral mucositis, and rubber-dam clamp placement. 

Infiltration Anesthesia

Infiltration Anesthesia is delivered to the terminal branches of the nerve and is confined to a small area of anaesthesia.It temporarily reduces sensation by inhibiting nerve impulse conduction, decreasing depolarization, increasing excitability, and preventing nerve action potential formation in a limited area.

Local anaesthetics are used for infiltration and nerve block anaesthesia, with the ideal choice depending on the procedure. Infiltration is commonly used for minor surgical and dental procedures, while nerve block is used for various procedures and pain management.

Areas of the mouth where infiltration anaesthesia is commonly used

infiltration anaesthesia

Local anaesthesia in dentistry can be given as either infiltration or block anaesthesia. Generally, infiltration anaesthesia is commonly used in the maxilla, whereas block anaesthesia is frequently used in the mandible.[6]

In addition, there are supplemental local anaesthesia techniques that can be utilized when infiltration and block methods have failed to achieve profound anaesthesia. Supplemental techniques include intraligamentary, intraosseous, intrapulpal, and interseptal anaesthesia.[7]

Managing Dental Anxiety and Discomfort

Sedation is a method used to control pain and relax during complex procedures like oral surgery or for those with anxiety. It can be injected or inhaled and can be used in three levels: mild (nitrous oxide), moderate (intravenous (IV) sedation), and deep (general anaesthesia).

Nitrous oxide is used for children and those with special needs, while IV sedation is used for longer procedures like wisdom teeth removal or dental implant surgery. General anaesthesia is used less often in dental practices.

Sedation dentistry is a moderate level of sedation that creates short-term amnesia, allowing patients to feel calm and relaxed during dental procedures. It is recommended for individuals with dental anxiety, fear of needles, extreme teeth sensitivity, claustrophobia, decreased sensitivity to local anaesthesia, difficulty controlling movements, and special needs. 

Who Can Benefit from Oral Sedation Dentistry?

Oral sedation dentistry is beneficial for patients with dental anxiety, strong gag reflexes, low pain threshold, and those requiring multiple procedures. It reduces the gag reflex, makes dental procedures easier, reduces discomfort, and makes the process more comfortable and efficient. Patients with a low pain threshold can also benefit from oral sedation dentistry.

Post-Anesthesia Care

To alleviate numbness after dental procedures, apply a warm compress to the affected area, get active or take a nap. Physical activity stimulates blood flow, while a nap helps relax and dissipate the numbness. There’s no one-size-fits-all answer for the duration of numbness, and factors like height, weight, and metabolism also play a role. 

Potential side effects of dental anaesthesia and their management

 Dental anaesthesia side effects vary depending on the type of anaesthetic used, with general anaesthesia having more risks than local or sedation. Common reactions include nausea, headache, shivering, hallucinations, delirium, confusion, slurred speech, dry mouth, pain at the injection site, dizziness, tiredness, numbness, and lockjaw caused by surgery trauma.


Talk to your dentist about your concerns about painful procedures or dental anxiety about anaesthesia, as they may have options to alleviate your anxiety and help you achieve dental wellness.

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