The success of adequate anesthesia is one of the major factors in patient cooperation towards dental treatments that involve pain. Treatment performed under incomplete analgesia will compromise the quality of the dental procedure performed and the patient's confidence in the dentist. The most commonly used technique for anesthetizing the mandibular molar during various treatments is the Inferior Alveolar Nerve Block (IANB). However, failure of complete analgesia after IANB occurs frequently, regardless of experience. This review summarizes various factors and reasons responsible for such failures and discusses in detail how to overcome them by various supplemental aids and alternative techniques. Therefore, clinicians, instead of giving a second shot of IANB, can systematically evaluate the reason for failure and rectify it by newer techniques, thereby substantially improving outcomes. It is mandatory for successful dental practice to be familiar with recent advancements, the indications, complications of alternative techniques, and implementing them in day-to-day practice.