Dental work often involves the extraction of teeth or cutting into the oral tissue. Due to the painful nature of the procedures involved, dentists use anesthetics to diminish the pain at the time of the operation. Most dentists use local anesthesia, which is the injection of agents that temporarily numb the nerves. Nitrous oxide is also used. It is an inhaled gas that diminishes the pain during the operation.
One potential side effect of dental anesthesia is the development of hematomas. Many dental anesthetics are given via injection. If the needle punctures a blood vessel, blood can seep and collect below the surface of the skin or the gum tissue. This leads to swelling and intense pain. Basically, the pain dissolves within 7-10 days without any treatment.
Local anesthetics for dental procedures are designed to numb the nearby tissues. Because it takes time for these to wear of, a patient may experience temporary paralysis or numbness in the mouth or the face. This can cause the eyelids or part of the face to droop. It can also make speech or eating difficult. Sometimes it causes a tingling effect all over the body, but this effect automatically disappears within a few months. This effect is known as paresthia.
In some cases the compounds used for dental anesthesia rapidly travel to the blood stream and are absorbed by the body. This primarily affects the brain, leading to toxicity of the central nervous system (CNS). CNS toxicity can cause unusual excitability and irritability coupled with a rapid heartbeat and difficulty in breathing. It can also cause sweating and paleness, as well as the sensation of being hot or cold. Patients can also develop double vision, confusion and in extreme situations convulsions or seizures.
Nitrous oxide has also a number of side effects when it is used. If too much is used it can cause hypoxia, which is a subnormal amount of oxygen in the blood. One sign of hypoxia is dizziness resulting from low oxygen flow to the brain. It can also cause air filled portions of the body to expand, so it should not be used if you have bowel obstructions sinus or middle ear problems or a collapsed lung.
The basic side effect is prolonged numbness. Generally anesthesia is given for few minutes or hours for completing the surgery but sometimes the numbness extends to last for days or months and this result in the patient biting his tongue or lips. In severe cases the numbness remains permanent.