Neurovascular plexus theory for "escape pain phenomenon" in lower third molar surgery

Abstract

Pain during extraction of impacted mandibular third molars which can occur despite adequate local anesthesia is termed as "escape pain phenomenon". Recently, it was described during elevation of a mesioangular impacted mandibular third molar and also while curetting an extracted third molar socket. This phenomenon has been overlooked, as it was previously considered secondary to pressure effect on the inferior alveolar neurovascular bundle (IANB). However, it is unlikely that the pain impulses originate from direct pressure on the IANB, as the nerve is blocked more proximally at its entry into the mandible. The authors speculated that the occasional presence of a neurovascular plexus (NVP) independent of the IANB causes the escape of a pain impulse upon stimulation by root pressure or instrumentation. To validate the presence of such a plexus, a meticulous literature search and review were performed. The search revealed evidence of the occasional presence of a NVP consisting of auriculotemporal and/or retromolar neural filaments. The plexus may be present around the inferior alveolar artery or embedded within the IANB, and does not innervate the tooth. This plexus likely propagates pain impulses only upon stimulation by compression or instrumentation in the apical area of the tooth socket. This theory explains the absence of pain during tooth sectioning and bone guttering in the presence of a complete inferior alveolar nerve block.

Common Anatomical Variations of Neurovascular Canals and Foramina Relevant to Oral Surgeons: A Review

“…This escape pain is related to the presence of nerve fibres in the RMC responsible for innervation of the retromolar triangle mucosa, buccal mucosa and gingiva of the mandibular posterior region [33].…”

The clinical significance of the retromolar canal and foramen in dentistry

“…Reviewing six cases of failed IAN block, Auluck, Pai, and Mupparapu (2007) reported the presence of a TMC in one case and BMCs in the other five. The presence of a RMC has been associated with the pain experienced during extraction or surgical removal of impacted mandibular third molars despite adequate local anesthesia, called the “escape pain phenomenon.” This escape pain is due to the nerve content of the RMC, which innervates the retromolar triangle mucosa, buccal mucosa, and buccal gingiva of the mandibular premolar and molar regions (Arakeri, Sagoo, & Brennan, 2015).…”

Clinical and electrophysiological evaluation of the lower alvelolar nerve status in patients after removal of radicular cysts by various methods

“…ϳñëÿ çàñòîñóâàííÿ â ïàö³ºíò³â ï'ºçîåëåêòðè÷íî¿ òåõí³êè åíóêëåà-ö³¿ ðàäèêóëÿðíèõ ê³ñò íèaeíüî¿ ùåëåïè âåëèêèõ ðîçì³ð³â â àíàëî´³÷íèé òåðì³í ñïîñòåðåaeåííÿ â íèõ áóëè íàÿâí³ ëèøå âèÿâè ëåãêîãî ñòóïåíþ ïîðóøåíü ôóíêö³¿ íèaeíüîãî àëüâåîëÿðíîãî íåðâàχ 2 =2,012 (p>0,05) (òàáë.1). Äî ïàòî´åííèõ ôàêòîð³â, ùî ñïðè÷èíþþòü íåé-ðîïàò³þ íèaeíüîãî àëüâåîëÿðíîãî íåðâà ïðè õ³ðóð´³÷íèõ ñòîìàòîëî´³÷íèõ âòðó÷àííÿõ íà íèaeí³é ùåëåï³, íàëåaeàòü: ìåõàí³÷íå òðàâìóâàííÿ ï³ä ÷àñ îïåðàö³¿ (³í'ºêö³éíîþ ãîëêîþ, áîðîì, ðó÷íèìè ³íñòðóìåíòàìè) [21,22], êîìïðåñ³ÿ çàïàëüíèì åêñóäàòîì òà ãåìàòîìîþ ñóäèííî-íåðâîâîãî ïó÷êà ï³ñëÿ îïåðàö³¿ [23,24], àëüòåðóþ÷èé âïëèâ ìåä³àòîð³â çàïàëåííÿ (ã³ñòàì³íó, ñóáñòàíö³¿ Ð, áðàäèêiíiíó, ïðîñòàãëàíäèíó Å2, ïðîçàïàëüíèõ öèòîê³í³â IL-1β, IL-6, TNF ) íà íåðâîâó òêàíèíó â ä³ëÿíö³ óðàaeåííÿ [25][26][27][28].…”