48 obstructive teeth is a special expression in the dental profession, refers to the right lower jaw wisdom teeth appear obstructed, is a diagnosis method. 8 refers to the eighth tooth, from the middle of the back to count the eighth tooth is exactly wisdom teeth, professional also called the third molar. In general, the dental profession will divide the mouth into 4 quadrants, the upper and lower jaws are the corresponding horizontal lines, the upper and lower center is the midline, thus divided into 1, 2, 3, 4, 4 quadrants corresponding to the right upper jaw, left upper jaw, left lower jaw and right lower jaw. The teeth of the right lower jaw are the 1-8 teeth headed by 4, and the 8th one is the wisdom tooth of the right lower jaw.