Local anesthesia 

Local anesthesia is used to numb the feelings in a specific part of the body. For dental treatments local anesthesia is the main method to prevent pain from any kind of procedure.

Conscious sedation with nitrous oxide

Nitrous oxide is the most common anesthetic in dentistry known as conscious sedation as well. Nitrous oxide used by inhalation, it has a minimal and moderate sedation effect. Conscious sedation overcomes anxiety and pain for the minor oral surgeries. It is generally used in patients where local anesthesia is not effective enough. You should avoid using contact lenses while a conscious sedation and having heavy meals before the conscious sedation.

General Anesthesia

Majority of the dental procedures can be performed under local anesthesia. General anesthesia is not an option for overcoming anxiety and pain, for some special cases like children and the patients with learning difficulties general anesthesia can be needed. Dental treatment with general anesthesia can be performed under the control of an anesthesiologist.

Conclusion

It is entirely up to the dentist's permission to decide on the type of anesthesia to be applied to you. If you have a special situation that your dentist should know about your health condition or pain threshold, by informing you can help your dentist to make the right decision.