Nerve membrane stabilization action of local anaesthetic agents is due to preventing conductance of Na ions from the exterior of the nerve to the interior.

The inferior alveolar nerve exits the mandibular foramen and runs in the mandibular canal before it branches off to supply the teeth, including the second premolar. To anesthetize the nerve at this point, the injection site is commonly located between the first and second premolars, inferior to the root apices, where the nerve is relatively superficial and accessible.

It is difficult to obtain local infiltration anaesthesia in the presence of inflammation/infection because of a decreased pH.

The best procedure to correct bimaxillary protrusion is extraction of four premolars and anterior alveolar segment repositioning. Bimaxillary protrusion is a condition where both the upper and lower jaws are positioned too far forward. This can be corrected by extracting the four premolars (two from the upper and two from the lower jaw) to create space for the teeth to move backward and then repositioning the anterior alveolar segments (the bone and gum tissue holding the front teeth) to achieve a more favorable facial profile and occlusion. This approach addresses the protrusion of both jaws simultaneously and is more effective than the other options listed, which are more targeted at specific jaw issues (mandibular body osteotomy and subcondylar osteotomy) and not as comprehensive for bimaxillary protrusion cases.

An open fracture is a fracture that communicates with the outside environment, typically through a wound. This increases the risk of bacterial infection