The maxillary second molar is the tooth located laterally from both the maxillary first molars of the mouth but mesially from both maxillary third molars. This is true only in permanent teeth. In deciduous teeth, the maxillary second molar is the last tooth in the mouth and does not have a third molar behind it. The deciduous maxillary second molar is also the most likely of the deciduous teeth to have an oblique ridge. There are usually four cusps on maxillary molars, two buccal and two palatal.