Jewish dentists may observe the Sabbath if they're particularly religious, and so they must consider this when making the decision of whether or not to treat a patient. What kind of emergency is warranted for breaking the Sabbath?
Suspending the Sabbath for a dental emergency
In the case of an emergency that's endangering the life of the patient, the Sabbath can be abrogated or suspended. Abrogation of the Sabbath means that it has been "cancelled", while suspension means that they can do things not permitted during the Sabbath for a set of time.
According to the codes of Jewish Law, if the physician suspends the Sabbath, it's his duty to perform all acts required for the care of his patient, and not just the ones that puts them out of danger (Mishneh Torah, Hilchot Shabbat 2:1 and Mishnah Berurah 328:14).
Definition of a life endangering situation
What does the Sabbath law consider a life endangering situation worthy of suspension? A danger to life situation is any situation in which
- If left untreated the issue will endanger the life of the patient immediately, or already is
- If left untreated the issue can develop into a life endangering problem for the patient
Any condition that features an infection or an abscess is considered life endangering because if left alone, the infection can spread to the brain. Conditions such as gum infections, jaw swelling, abscesses are in this category. Otherwise, the Jewish dentist should consider, in the scope of their medical knowledge, if the issue is a danger to their patient's life or not.
The loss of a tooth isn't life endangering, but it's considered by certain scholars to warrant suspending the Sabbath if preventable because of the laws in place that consider "saving/ preserving a limb" a medical practice worth of Sabbath suspension.
Alternatives for Jewish dentists to breaking the Sabbath
If the Jewish dentist doesn't feel comfortable with suspending the Sabbath for more than a life endangering issue, they may refer the patient to a non-Jewish dentist for the rest of the dental care needed.
If Jewish dentists don't want to suspend the Sabbath at all, they should refer their patient to a non-Jew for full treatment. Thus, it would be advisable for all Jewish dentists and their patients to keep handy the contact details of a non-Jewish dentist.
There is some scholarly discourse (revolving around the Mishneh Torah, Hilchot Shabbat 2:3 ) that it's the Jewish dentist's duty to perform on the patient in the case of a life endangering problem, and that referring them to a non-Jew breaks Jewish Law, but it's still up for debate. For further assistance, consult resources like Whole Health Dentists.