Malocclusion Angle's classification:Malocclusions can be divided mainly into three types,based on the relative position of the maxillary 1st molar. The mesiobuccal cusp of the upper first molar should rest on the mesiobuccal groove of the mandibular first molar. 190 NIVER Malocclusion Angle's classification: Malocclusions can be divided mainly into three types, based on the relative position of the maxillary 1st molar. The mesiobuccal cusp of the upper first molar should rest on the mesiobuccal groove of the mandibular first molar