Concepts of accidental overfilling and over instrumentation in the mandibular canal during root canal treatment

It has been well established that overfilling should be avoided during obturation. Overfilling of the root canal is indicated only in those cases which will be followed by apicoectomy, when the foreign material will be removed. Accidental overfilling may occur with soft material (for example, certain, pastes and cements) or with hard material (such as gutta-percha or silver cones). Such overfilling may cause an unnecessary mechanical and chemical irritation, which hinders repair of the periapical tissue and thus diminishes the probability of a successful prognosis. The patient may experience sharp, localized postoperative pain, which gradually disappears. When the mandibular nerve is injured, the pain is not only located in the immediate periapical area, but radiates to the whole area innervated by the injured nerve. The purpose of this paper is to present seven cases which demonstrate the occurrence of damage to such nerve fibers during root canal treatment and, in addition, to outline clinical management policy in the event of such complications. The seven cases are summarized in Table 1.