The appearance of normal teeth varies, especially the molars. Abnormally shaped teeth can result from many different conditions. Specific diseases can have a profound effect on tooth shape, tooth color, time of appearance, or absence of teeth. Update Date: 05/28/2008Jason S. Baker, DMD, Oral and Maxillofacial Surgeon, Private Practice, Yonkers, New York. Review provided by VeriMed Healthcare Network