48. Angle diagnostic system. Flashcards
- The angle classification?
based on: anteroposterior relationship of the jaws
- Class I molar (65%) - neutralocclusion
- Class II molar (30%) - distocclusion
- Class III molar (5%) - mesiocclusion
- The angle classification
a/ Characteristics of Angle I. Neutralocclusion
- Mesiobuccal cusp of maxillary 1st molar, occluded to the mesiobuccal groove of mandibular 1st molar
- The molar relationship of occlusion is normal but incorrect line of occlusion
- The angle classification
b/ Problems of Angle I. Neutralocclusion
- Crowding, narrowing, lack of place
- Open bite
- Diasthema medianum
- Impacted wisdom teeth
- The angle classification
c/ Characteristics of Angle II. - Distocclusion
1/ The mandible is backword or/and the maxilla is forward
2/ 2 divisions:
- Division 1: maxillary anterior teeth protruding
- Division 2: maxillary central incisors retroclined and lateral teeth overlapping
- The angle classification
d/ characteristics of Class III – mesioocclusion
Types for Class III
1/ true class III – skeletal origin, genetic, excessive mandible or smaller than normal maxilla
2/ pseudo class III – false or postural origin
- mandible shifts forward during last part of closure due to contact of incisors with canines
- due to premature loss of deciduous posterior teeth
3/ Class III subdivision – class III on one side only. Normal or Class I on the other side
What are the treatments of class III
1/ Real prognathism Surgery after the age of 18 (for boys sometimes even later)
2/ Pseudoprognathism
- The etiology of this anomaly is the underdeveloped maxilla
- It should be treated in the early mixed dentition
- Types of treatments: Hyrax – DeLaire-maszk Hansa III, Frankel III
3/ Milder skeletal anomalies – functional problems –
dentoalveolar compensation – (if the incisors can be adjusted into an edge-to-edge bite)
- Fixed appliance
- Frankel III., Hansa III.
