?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Is+there+a+%22safety+zone%22+in+the+mandibular+premolar+region+where+damage+to+the+mental+nerve+can+be+avoided+if+periapical+extrusion+occurs%3F&rft.creator=Ngeow%2C+Dr.+W.C.&rft.subject=JOURNALS&rft.subject=Online+Journal+of+Health+and+Allied+Sciences&rft.description=The+mandibular+premolars+are+located+close+to+the+mental+foramina+(Fig.+1).+As+such%2C+various+events+affecting+these+teeth%2C+such+as+odontogenic+infection1+and+orthodontic%2C+endodontic%2C+periodontal+or+surgical+misadventure%2C+may+result+in+neurosensory+disturbance+of+the+mental+nerves.2-4+In+one+retrospective+study%2C+the+incidence+of+mental+paresthesia+resulting+from+periapical+infection+or+pathology+was+0.96.+In+another+0.24+of+cases+in+the+same+study%2C+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%2C+periodontal+and+surgical+misadventure+cannot+be+determined+but+is+presumably+low%2C+as+most+such+cases+have+been+reported+as+individual+case+reports.+In+endodontology%2C+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%2C+mechanical+preparation+and+filling+should+be+limited+to+the+root+canal%2C+as+overinstrumentation+or+extrusion+of+chemical+fillings+beyond+the+apical+foramen+to+the+adjacent+nerve+may+give+rise+to+neurosensory+disturbances+such+as+anesthesia%2C+paresthesia+or+dysesthesia.5+Unfortunately%2C+cases+of+endodontic+extrusion+of+various+filling+or+irrigation+agents+continue+to+be+reported%2C+despite+recent+advances+in+endodontology.&rft.publisher=CANADIAN+DENTAL+ASSOC%2C+1815+ALTA+VISTA+DRIVE%2C+OTTAWA%2C+ON+K1G+3Y6%2C+CANADA&rft.date=2010-06-16&rft.type=Journal+(Paginated)&rft.type=PeerReviewed&rft.format=application%2Fpdf&rft.identifier=http%3A%2F%2Fcogprints.org%2F8191%2F1%2FIs%2520there%2520a%2520safety%2520zon%2520in%2520the%2520mandibular%2520premolar%2520region%2520where%2520damage%2520to%2520the%2520mental%2520nerve%2520can%2520be%2520avoided%2520if%2520periapical%2520extrusion%2520occurs.pdf&rft.identifier=++Ngeow%2C+Dr.+W.C.++(2010)+Is+there+a+%22safety+zone%22+in+the+mandibular+premolar+region+where+damage+to+the+mental+nerve+can+be+avoided+if+periapical+extrusion+occurs%3F++%5BJournal+(Paginated)%5D+++++&rft.relation=http%3A%2F%2Fcogprints.org%2F8191%2F