Orthodontics Angle’s Classification British Standard Incisor Classification

Angle’s Classification Described by Edward H Angle in 1899 based on relative AP position of the first molars Angle assumed that first molars erupted in constant position within the arches so their r/ship could be used to identify AP skeletal r/ship

Angle classification of malocclusion classificationNotes Class IBuccal groove of the mandibular first permanent molar should occlude with the mesio-buccal cusp of maxillary first molar. This is considered to be a normal relationship. Class IIThe buccal groove of the mandibular first permanent molar occludes posterior to the mesio-buccal cusp of the maxillary first molar. The degree of discrepancy is described as a fraction of the mesio-distal width of a premolar unit. division 1The maxillary central incisors are proclined or normally inclined and the overjet is increased. division 2The maxillary central incisors are retroclined Class IIIThe buccal groove of the mandibular first permanent molar occludes anterior to the mesio-buccal cusp of the maxillary first molar.

British Standard Incisor Classification (BSI) A classification of malocclusion based on the incisors is advantageous as treatment is often primarily aimed at correcting this relationship. In clinical practice this is often used in association with the Angle’s molar relationship.

British Standard Incisor Classification (BSI) Incisor ClassificationDefinition Class IThe lower incisor edges occluded on or lie below the cingulum plateau of the upper incisors. Class II, division 1The lower incisor edged occluded behind the cingulum plateau of the upper incisors and the upper incisors are normally inclined or proclined. Class II, division 2The lower incisor edges occluded behind the cingulum plateau of the upper incisors and the upper incisors are retroclined. Class IIIThe lower incisor edges occlude anterior to the cingulum plateau of the upper incisors.