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Root canal Ssort fill

Filling of the root canal should be completed within a millimeter of the root tip or apex. Short fills exceeding 2 millimeters, predispose to bacterial contamination of the underfilled root canal with resulting abscess or chronic inflammation necessitating retreatment, surgical endodontics or extraction.

Root canal overfill

Filling of the root canal should end at the root tip apex. Overextended filling materials can penetrate the underlying main sensory nerve in the lower jaw or into the sinus in the upper jaw causing a chemical burn to sensitive nerve tissue. Persistent numbness and/or pain in the lip and chin is symptomatic of overfill of lower posterior teeth. A posttreatment xray will show the overfill. If overfill impinges the lower jaw nerve, a 3D xray should be taken and referral to a maxillofacial microsurgeon to evaluate for immediate decompression surgery to remove the overfill before the nerve becomes irreversibly injured from chemical toxicity and inflammatory compression which compresses blood supply and causes sensory nerve death or necrosis. Microsurgery beyond 48 hours decreases the likelihood of reversibility, and increases the likelihood of permanent burning pain or numbness of the lip, chin, and gums.

If numbness persists 6 hours after root canal therapy, the patient should telephone the treating dentist or endodontist for re-evaluation and consultation for immediate referral to a microsurgeon for surgical removal of any overfill into the inferior alveolar nerve canal. Literature shows complete numbness reversal if microsurgical removal of root canal overfill materials inside the inferior alveolar nerve canal are surgically removed within the first 48 hours and partial numbness improvement if microsurgically removed within 3 months. Furthermore, if microsurgical inferior alveolar nerve decompression is treated in the first three months, improvement has been shown in two thirds of endodontic overfill cases. Thus time is of the essence for immediate microsurgery for surgical removal of root canal overfills located inside the inferior alveolar nerve canal.

Some root canal filling pastes are not FDA approved and contain harmful toxic paraformaldehyde and lead which mummify sensory jaw nerves. No U.S. dental school has recommended these pastes for over a decade. Nevertheless the American Endodontic Society (AES), which is not ADA (American Dental Association) affiliated, advocates these paraformaldehyde containing pastes which are notorious for causing permanent lip and chin numbness and/or pain. These unnecessarily toxic root canal filling pastes are known as Sargenti paste, N2 and RC2B. By contrast, the American Association of Endodontists, which is the ADA recognized speciality group, regards the use of paraformaldehyde containing root canal fillers or paste as substandard practice. See Sargenti Opposition Society and our article Ethics and Informed Consent for more information.


Filing instruments or placement of posts on completion of root canal treatment may penetrate the root side and cause an abscess or endodontic failure. Midtreatment xrays can avoid this mishap with careful measurements ensuring instruments are placed inside the root canal space and not off angled and out the root side. Three-dimensional xrays, known as Cone Beam CT, will aid in diagnosis if a perforation has occurred. The best 3D imaging for endodontic diagnosis is the J. Morita Corporation's Accuitomo CBCT machine. The Accuitomo is the least expensive to the patient, offers the least radiation and provides the highest resolution.


Root formed implants surgically placed in the bone are predictably long lasting and are preferable to bridges for tooth replacement. Bridges necessitate grinding down adjacent teeth for replacement of a tooth and require bridge cleaners for flossing underneath the bridged false tooth.

Implants drilled too deep can penetrate the underlying main sensory jaw nerve and cause permanent lip and chin numbness and/or pain. 3D xrays show the exact position of the jaw nerve and guide the surgeon preoperatively where to place the implant drill to avoid injury to the sensory jaw nerve. If severe pain and/or numbness persists 6 hours after implant placement surgery, the implant should be removed. A three dimensional cone beam (CBCT) xray can show if the jaw nerve was penetrated with the implant drill. A two millimeter safety zone between the implant drill depth and underlying jaw nerve has been recommended for over a quarter of a century. Nevertheless some implantologists ignore or disregard this precaution and endanger patients by causing permanent jaw nerve injuries of numbness, burning pain and/or by invading the two mm. danger zone and "harpoons" the inferior alveolar nerve with the implant drill and/or implant.

For implants, consult a periodontist in your area. For a free oral health brochure samples including one titled "Dental Implants: Teeth That Look and Feel Just Like Your Own" are available by calling 800-FLOSSEM or at the American Academy of Periodontology's web site.