Actuallythis is a complication that can occur on about 3% of wisdom teeth extractions. It is called paresthesia of the mandibular and lingual nerves. These nerves are present  very close to the lower right wisdom tooth, and while removing the tooth, they sometimes get  injured and this leads to numbness in the areas supplied by these nerves. That is why theright side of the tongue is still numb. Almost always, with time, the feeling will return to the lip and tongue on that side, but since nerve tissue heals very slowly, it will take quite a while. How long depends on how badly the nerves were damaged. It could take weeks or several months, before things get back to normal.You can go back to ur dentist and have a word with him on this complication however it will take time to heal , may be weeks or months ...................for more info refer the link.................................http://www.identalhub.com/forum_wisdom-tooth-numbness-after-2-weeks-of-extraction-2955.aspx