Is there a "safety zone" in the mandibular premolar region where damage to the mental nerve can be avoided if periapical extrusion occurs?

Ngeow, Dr. W.C. (2010) Is there a "safety zone" in the mandibular premolar region where damage to the mental nerve can be avoided if periapical extrusion occurs? [Journal (Paginated)]

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The mandibular premolars are located close to the mental foramina (Fig. 1). As such, various events affecting these teeth, such as odontogenic infection1 and orthodontic, endodontic, periodontal or surgical misadventure, may result in neurosensory disturbance of the mental nerves.2-4 In one retrospective study, the incidence of mental paresthesia resulting from periapical infection or pathology was 0.96. In another 0.24 of cases in the same study, mental paresthesia was a complication of root canal treatment (caused by severe overfill in one case and iatrogenic perforation of mechanical instrumentation through the root and into the mental nerve in the second case).1 The incidence of mental paresthesia resulting from orthodontic, periodontal and surgical misadventure cannot be determined but is presumably low, as most such cases have been reported as individual case reports. In endodontology, elimination of infection from the pulp and dentin followed by adequate intracanal preparation and proper sealing constitute the basic principles of root canal treatment. Ideally, mechanical preparation and filling should be limited to the root canal, as overinstrumentation or extrusion of chemical fillings beyond the apical foramen to the adjacent nerve may give rise to neurosensory disturbances such as anesthesia, paresthesia or dysesthesia.5 Unfortunately, cases of endodontic extrusion of various filling or irrigation agents continue to be reported, despite recent advances in endodontology.

Item Type:Journal (Paginated)
Additional Information:Times Cited: 0 Ngeow, Wei Cheong
Keywords:Inferior Alveolar Nerve; Paresthesia; Foramen
JOURNALS > Online Journal of Health and Allied Sciences
ID Code:8191
Deposited By: Ngeow, A.P. Dr. Wei Cheong
Deposited On:25 Apr 2012 13:00
Last Modified:25 Apr 2012 13:00

References in Article

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1. Knowles KI, Jergenson MA, Howard JH. Paresthesia associated with endodontic treatment of mandibular premolars. J Endod. 2003;29(11):768-70.

2. Baxmann M. Mental paresthesia and orthodontic treatment. Angle Orthod. 2006;76(3):533-7.

3. Scarano A, Di Carlo F, Quaranta A, Piattelli A. Injury of the inferior alveolar nerve after overfilling of the root canal with endodontic cement: a case report. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2007;104(1):e56-9.

4. Pogrel MA, Thamby S. The etiology of altered sensation in the inferior alveolar, lingual, and mental nerves as a result of dental treatment. J Calif Dent Assoc. 1999;27(7):531, 534-8.

5. Pogrel MA. Damage to the inferior alveolar nerve as the result of root canal therapy. J Am Dent Assoc. 2007;138(1):65-9.

6. Fishel D, Buchner A, Hershkowith A, Kaffe I. Roentgenologic study of the mental foramen. Oral Surg Oral Med Oral Pathol. 1976;41(5):682-6.

7. Phillips JL, Weller RN, Kulild JC. The mental foramen: 2. Radiographic position in relation to the mandibular second premolar. J Endod. 1992;18(6):271-4.

8. Denio D, Torabinejad M, Bakland LK. Anatomical relationship of the mandibular canal to its surrounding structures in mature mandibles. J Endod. 1992;18(4):161-5.


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