Difficulty in mouth opening can occur after wisdom teeth extraction due to muscle trismus. TMJ dysfunction may also rarely occur after wisdom tooth extraction and can lead to difficulty in mouth opening. In case of muscle Trismus, patient is advised to stretch his mouth. In stretching of mouth you don’t have to wide open the mouth but open the mouth till pain is there and don’t go beyond that. If you can easily put your 3 fingers in mouth that means the opening is normal and if it is less then you have to try to open more and more gradually till you are able to put 3 fingers in the mouth.TMJ dysfunction after teeth extraction is unusual and temporary and to treat condition, heat therapy, anti-inflammatory meds and splint therapy can be given. You can continue with warm saline rinses for faster healing to take place. Keep tooth extraction socket area clean to avoid any secondary infections. It may take 3 weeks to 3 months for complete healing of wisdom tooth extraction socket to take place depending on method of teeth extraction and trauma to supporting tissues during tooth extraction. If mouth opening doesn’t seem to get better, then you can visit your oral surgeon for evaluation.  For more info on complications after teeth extraction, visit……    http://www.identalhub.com/dental-complications-after-tooth-extraction-881.aspx