Nerve injury can be related to mechanical, chemical, and thermal factors. Infection-related paresthesia is usually related to mechanical pressure and ischemia associated with the inflammatory process. Another cause of paresthesia could be the toxic metabolic products of bacteria or inflammatory products released following tissue damage. This article presents cases of inferior alveolar and mental nerve paresthesia caused by an infected impacted tooth, an infected cyst, and periapical infection. The possible pathophysiologic mechanism of nerve injury, therapy, and prognosis for recovery are also discussed.