The answer to this question depends on what types of symptoms do you have related to your teeth and why do believe you have gingivitis. Have you had any discoloration or your teeth. pain with hot or cold foods, or loose teeth? These are things to consider and discuss with your dentist
as they will be best able to evaluate your medical history, clinical exam and presenting symptoms and decide upon the appropriate course of treatment. This may include labs tests, imaging studies and perhaps a referral if deemed medically appropriate.
In general, if it is a concern for teeth cleaning, then a dentist should be able to treat a majority of the concerns that you may have. If it is beyond their scope, they will be able to refer you as necessary. But the most important first step is to be evaluated by a dentist as they will be able to best decide upon the appropriate course of treatment and the various options available. Also, it is important to discuss with them what they recommend in regards to proper oral hygiene. including daily flossing and brushing of your teeth. Also regular dental visits are very important to prevent worsening infections.