Sydney,
Having been a surgical chairside dental assistant for 30+ years, I have seen many, many injections given to patients, including ozone. With that said, it is SO imperative that you know what is being injected into your mouth because whatever it is will filter through your blood stream, major organs and renal collecting system. It has been my experience that some dentists are just so use to using lidocaine that they are not aware of the data stating the high toxicity rate and therefore they tend to misuse it sometimes. Here is a website that gives a brief synopsis of lidocaine use:
http://wiki.bmezine.com/index.php/Lidocaine_Toxicity

Ozone injections are more commonly used in dentistry than most people realize. In fact some dentists administer them <with good intentions of helping the patient>, but do not tell the patient that that's what they injected. In some states, oral ozone injections administered by a dentist are illegal. Oral Ozone injections are very painful and a topical gel is usually put on the site to be injected prior to the acutal injection. Sometimes a little bit of lidocaine or carbocaine local anesthetic is then injected to help minimize the pressure/pain from the injection of ozone. The post operative results of ozone injections can be beneficial or detrimental, depending on the condition being treated.

Another thing many people do not realize. All injectable material is chemically balanced and premeasured in a laboratory before being placed in a sealed glass carpule. The only way for a dentist to make up his own remedy would be either 1) He has a compounded pharmacist or specialized lab that creates a concoction for him or 2) He empties a glass carpule of anesthetic and somehow refills it with something else.

It may be wise to ask your dentist:
1) what is in the injection
2) is it something he makes up himself
3) what is the long term benefit of these injections
4) what are the short and long term risks of these injections

I offer you this information to hopefully make you a bit skeptical about further treatment until you know what is actually being used. I have seen countless, unnecessary complications occur in patients who have had dental treatment administered to them incorrectly.

Please let us know what you find out :-)

Bryanna