2/26: Occlusal Examination and Evaluation Flashcards
What is malocclusion?
A condition in which there is a deflection from the normal relation of the teeth to other teeth in the same arch and/or to teeth in the opposing arch
What is angle’s classifications based on?
The relationship of the MB cusp of the maxillary 1st molar and the buccal groove of mandibular 1st molar
What is angle’s class I?
MB cusp of max 1st molar
bisects buccal groove of
mand 1st molar
What is class 1 malocclusion?
Same as normal occlusion but characterized by crowding, rotations, and other positional irregularities
What is angle’s class II?
MB cusp of max 1st molar is
mesial to mand 1st molar’s
buccal groove
- “overbite”
What is angle’s class III?
MB cusp of max. 1st molar is distal to buccal groove of mand 1st molar
- “underbite”
What is overjet?
The horizontal overlap of the maxillary central incisors over the mandibular central incisors
What is overjet measured by?
Periodontal probe
- usually 2-3mm
What is overbite?
The vertical overlap of the maxillary central incisors over the mandibular central incisors
- how much of the maxillary teeth cover up the mandibular teeth
How is overbite measured?
Using the probe vertically
- normal overbite is usually 2-3mm or approx 20-30% of the height of the mandibular incisors
What is anterior crossbite?
The horizontal growth of the mandible exceeds the horizontal development of
the maxilla, and the lower anterior teeth end up in front of the upper anterior
teeth
What can anterior crossbite result from?
Underdevelopment of the maxilla
What is the etiology of dental wear?
multifactorial with complex relationships between attrition, abfraction, abrasion and erosion
What is erosive tooth wear classified according to?
The specific mechanism that is responsible for the wear
What are classifications of erosive tooth wear?
- erosion
- ebfraction
- abrasion
- attrition
What is evidence of bruxism?
- Bony ridges-exostosis, tori
- Gingival recession
- Abfractions- loss of cervical area due to bruxism
- Broken teeth & restorations
- Excessive attrition
What is evidence of occlusal wear/trauma?
- Wear facets
- Broken restorations
- Chipped teeth
What is attrition?
Mechanical wear of the incisal or occlusal surface as
a result of functional or para-functional movements
of the mandible (tooth-to-tooth contact)
What accelerates attrition?
Bruxism
What can attrition be related to?
Age
What is abfraction?
Wear along the gingival margin that is not caused by acid activity
What is the shape of abfraction?
Cervical wedge-shaped defects
What can bruxism result in?
Abfractions because cervical area of the tooth flexes under the load
What is abrasion?
Abnormal tooth surface loss
resulting from direct frictional forces between the teeth and external objects or from frictional forces between contacting teeth in the presence of an abrasive medium
