Several levels of sedation dentistry are available today, ranging from simple anxiolysis (minimal sedation) to deep sedation and general anesthesia (full loss of consciousness). Dental Sedation is a technique that can be used to relieve dental anxiety to allow patients to receive the dental treatment they need. Which level of sedation dentistry is the most suitable for each customer depends on his individual needs and physical condition.
The American Society of Anesthesiologists, recognizing that sedation is a continuum, has defined the terms for the range of sedation beginning with minimal sedation (“anxiolysis”), progressing to moderate sedation, deep sedation, and finally, general anesthesia. These terms are defined by the patients’ response to various stimuli and their implications to maintaining the airway, spontaneous ventilation and cardiovascular function.
The table below illustrates the different levels of sedation dentistry:
|Levels of Dental Sedation|
|Minimal Sedation (Anxiolysis)||Moderate Sedation||Deep Sedation||General Anesthesia|
|Responsiveness||Normal response to verbal commands||Purposeful response to verbal/touch||Response after repeated or painful stimulation||No response, even to painful stimulation|
|Airway||Unaffected||No Assistance Needed||Assistance may be Required||Assistance Required|
|Spontaneous Ventilation||Unaffected||Adequate||Possibly Inadequate||Usually Inadequate|
|Cardiovascular Funtion||Unaffected||Usually Maintained||Usually Maintained||Possibly Impaired|
There are several levels of sedation dentistry used to allow patients to experience a very calm state so they can comfortably tolerate their dental treatment, each putting the patient in different states of relaxation:
This is the lightest form of sedation dentistry, also known as ‘anxiolysis’ which comes from the Greek word for “anxiety relief”. Minimal sedation is suitable for patients with low levels of anxiety problems, and it generally provides adequate relaxation for light procedures or routine visits to the dentist.
Anxiolysis describes a minimally depressed level of consciousness, which can be achieved by administering an oral or inhaled sedative agent in order to eliminate patient’s anxiety. The patient is relaxed but remains fully awake and continues to respond normally to physical stimulation and verbal commands. Although cognitive function and coordination may be modestly impaired, ventilatory and cardiovascular functions are unaffected. The patient can independently and continuously maintain breathing and body reflexes are not affected.
Dentists are generally licensed to provide medication for anxiolysis without the need of special permit or training, as long the as the medication is given within the dosage limits recommended by the drug’s manufacturer for anxiolytic purposes without reaching the level of depressed consciousness.
To provide minimal sedation the dentist may administer nitrous oxide (at a small concentration) which the patient breaths through a mask, or prescribe an oral sedative in the form of a pill to be taken on the night before or some time prior to the procedure (oral sedation).
Moderate sedation is the level of dental sedation which is generally described by the term “conscious sedation”. High-anxiety patients or patients needing a lot of dental work are the best candidates for moderate sedation.
Moderate sedation is defined as a drug-induced depression of consciousness during which patients can respond purposefully to verbal commands, either alone or accompanied by light stimulation. Cardiovascular function and protective reflexes are normal or minimally altered.
Moderate Conscious Sedation puts patients into a sleepy state but they remain awake and conscious, maintaining the ability to breath on their own and follow the dentist’s instructions. Sometimes the patient is so relaxed that may fall asleep, but can be waken up easily. Patients usually have little or no memory of what has occurred during their sedation appointment.
Sedation dentists offering moderate sedation must have additional training and must obtain special licensing from the local dental authorities. The sedation dentist must have the training and experience to maintain a margin of safety in the drugs and/or techniques used in order to avoid the accidental loss of patient’s consciousness.
Conscious sedation can be achieved by either inhalation (nitrous oxide), oral, or intravenous sedation. Regardless of the administration method, moderate sedation provides an excellent balance between potency, safety and ease of use for most patients.
Deep sedation is a level of dental sedation which is considered to stand on the limits between conscious sedation dentistry and unconsciousness (general anesthesia). It is a less commonly used sedation method, used for patients who suffer from a very high level of anxiety and severe fear of the dentist, uncooperative children and people undergoing long or intense procedures like oral surgery.
Deep sedation is defined as a drug-induced state of depressed consciousness during which patients cannot be easily aroused and/or to respond purposefully to physical stimulation or verbal command but only following repeated or painful stimulation. The ability to breath may be impaired and patients may require assistance in maintaining a patent airway due to the partial loss of protective reflexes. Cardiovascular function is usually maintained.
The most common method of administering deep sedation is intravenously (IV sedation) through a needle inserted into a vein in the hand. The medicine used in deep sedation can take hours to fully wear off, therefore a friend or family member must be available to take the patient home after the appointment.
Deep Sedation can be administered only by an anaesthesiologist or highly trained oral surgeon. Because of the fact that the boundaries between deep sedation and general anesthesia may not be always clear, in some countries it is considered as equivalent to GA and can be administered only by an anaesthesiologist, an oral surgeon or a properly trained and licensed dental anesthesiologist.
General Anesthesia is the deepest level of sedation dentistry, in which the patient is fully unconscious during the entire procedure. This technique is usually reserved only for patients with extreme dental phobia, mentally or physically disabled, or who are undergoing very invasive procedures, such as maxillofacial surgery.
General Anesthesia is defined as a drug-induced loss of consciousness during which patients are not arousable, even by painful stimulation. Protective reflexes may be completely lost, and ventilatory and cardiovascular function are often impaired. Patients may require assistance in maintaining a patent airway, and positive pressure ventilation may be needed because of depressed spontaneous ventilation.
General anesthesia can only be administered by an anesthesiologist, dental anesthesiologist or oral and maxillofacial surgeon. Because of the higher risks involved and the advanced requirements for patient monitoring, it is usually performed in a hospital surgical environment.
The level of sedation that a patient needs is based on their level of anxiety, their medical history, their response to a particular level of sedation, and finally on the characteristics of the procedure to be performed (duration, invasiveness).
Some will respond fine to a minimal level of sedation, whereas others may require a deeper level of sedation to achieve the same degree of relaxation. A specific patient may also require different level of sedation for different procedures; minimal sedation may be enough for a routine dental cleaning, but moderate or deep sedation may be preferred for an oral surgery procedure.
Whenever a patient needs a procedure that requires some degree of relaxation, the sedation dentist must evaluate and propose the possible options and discuss with the patient the advantages, disadvantages and risks related with each method, either minimal, moderate or deep sedation so that they are fully aware of what is involved with each type.
It’s a general rule that the deeper the sedation level, the higher the risk, as breathing and cardiac function may be affected. With moderate sedation, risk is generally much lower, and dentists may prefer this level of sedation due to its decreased risk to patient health.