Dentition mammals the infants have a set of teeth that fall out and are replaced by adult teeth. These are called deciduous teeth, primary teeth, baby teeth or milk teeth. Animals that have two sets of teeth, one followed by the other, are said to be diphyodont. Normally the dental formula for milk teeth is the same as for adult teeth except that the molars are missing. Because mammal teeth are specialised for different functions, many mammal groups have lost teeth not needed in their adaptation. Tooth form has also undergone evolutionary modification as a result of natural selection for specialised
U Should've Known Better April 2004, and features rapper Young Buck appears in the video as her love interest. The video follows the single's topic of a misunderstandings in a relationship, showing Monica as the girlfriend, with the boyfriend held in a Mexico hold-prison. With Monica getting help from a guy friend, her boyfriend's best friend sees them and thinks otherwise. Monica drives through the desert of Mexico to get him out of prison. The video ends with Monica and her boyfriend hugging at the end and going home together. The "U Should've Known Better" video premiered worldwide in May 2004 at the end