Final answer:
When a needle does not contact the bone during an inferior alveolar nerve block, there can be soft tissue penetration, hemorrhage, facial nerve paralysis, or trismus. These complications can be avoided with proper injection techniques. The options (a), (b), (c), and (d) are correct.
Step-by-step explanation:
If a needle does not contact the bone when administering an inferior alveolar nerve block, the following conditions may happen:
- Penetration of soft tissue - The needle may penetrate the soft tissue, leading to possible discomfort or inadequate anesthesia.
- Hemorrhage - Accidental puncture of blood vessels in the soft tissue can cause hemorrhage.
- Facial nerve paralysis - If the anesthesia is deposited in the vicinity of the facial nerve, it might temporarily paralyze the muscles of facial expression.
- Trismus - This is characterized by difficulty in opening the mouth. It can occur due to trauma to the muscles or blood vessels near the injection site.
When administering an inferior alveolar nerve block, it is crucial to inject anesthesia into the lateral wall of the oral cavity at a point before where the sensory nerve enters the mandibular foramen, avoiding these potential complications. Therefore, options (a), (b), (c), and (d) are correct.