Etiology of Malocclusions Part 2 Flashcards
what is a deep bite caused by
- skeletal
- overeruption of incisors
- undereruption of molars
the transverse is usually a _____ deficiency
maxillary transverse
what are transverse dimension deficiencies caused by
- overdeveloped mandible
- unfavorable dental angulations
what are the disturbances of dental development
- congenitally missing teeth
- malformed and supernumerary teeth
- interference with eruption
- ectopic eruption
- early loss of primary teeth
how common is anodontia
very rare
what is oligodontia
several teeth missing
what are Dr. Moyer’s explanations for congenitally missing teeth
- heredity
- ectodermal dysplasia
- localized inflammations or infections
- systemic conditions e.g. ricketts
- evolutionary changes in the dentition- especially third molars
what features are seen in ectodermal dysplasia
- oligodontia
- poorly shaped teeth
what are the most frequently missing teeth
- upper lateral incisors
- lower second premolars
- lower central incisor
what are the commonly malformed teeth
- peg maxillary lateral incisors
- crown may be misshaped
- root may be shortened
what is the mesio- distal size of the dentition
proportionality of tooth sizes within a dentition
what is another name for the mesio-distal size of the dentition
bolton ratio
what is the bolton ratio
the size of the lower dentition in relation to the size of the upper dentition
in order to develop a proper overbite and overjet:
the size of the lower dentition must be proportional to the size of the upper dentition
what is the overall bolton ratio
sum of mandibular 6-6mm/ sum of maxillary 6-6mm
