Orthodontic therapy Flashcards
Basic flashcards for Orthodontic therapy/nursing students
Name 3 types of orthodontic appliances
Fixed
Functional
Removable
What is proclination?
The upper and lower incisors are inclined labial to a greater degree than normal
What is retroclination
The upper and lower incisors are inclined palatal
to a greater extent than normal
Name 3 components of a URA
Base plate, retentive components, active components
Name the components of a fixed appliance
Brackets Bands Ligatures Archwires Auxiliaries
What is a class I (incisor relationship)
The lower incisal edge occludes below the cingulum plateau of upper incisors.
What is a Class II Div I (incisor relationship)
The lower incisal edge occludes behind the cingulum plateau of upper incisors. Upper incisors are usually inclined or proclined and overjet usually increased.
What is a Class II Div II (incisor relationship)
The lower incisal edge occludes behind the cingulum plateau of upper incisors. Upper incisors usually retronclined and overbite usually increased.
What is a Class III (incisor relationship)
Lower incisal edge occludes anterior to cingulum plateau of upper incisors. Overbite edge to edge or in reverse.
What is the curve of spee?
Flat occlusal plane
Define the term scissor bite?
One or more buccal segment teeth occlude entirely buccal to the lower arch teeth
What amount of force is required intrusion?
10-20gm
What amount of force is required for extrusion and tipping?
35-60gm
What amount of force is required for bodily movement?
70-120gm
What are the limitations of orthodontic treatment?
Medical history Dental history Patient compliance Hypodontia Tooth size discrepancy Skeletal discrepancy
What are the stages of Orthodontic treatment?
Planning
Active
Retention
Describe the sequencing of archwires.
Levelling & aligning
Space closure
Finishing & detailing
What is parallax?
The principle of radiographic parallax is employed to determine whether the impacted canine is placed buccal or palatal to adjacent teeth.
What force is required for anchorage?
20-25 gm
What is anchorage?
The resistance to unwanted tooth movement
Explain Newton’s 3rd law
To every action, there is an equal and opposite reaction
Name as many methods of anchorage as you can
Transpalatal arch Nance Elastics URA TAD's (temporary anchorage device)
On average how many (mm) reduction in the overjet should we expect per month?
1mm
What are TAD’s, and what do they do?
Temporary anchorage device, used as headgear alternative, aid space closure, help create asymmetric arches.
Why would you use a NITI coil spring?
Space closure and OJ reduction
Name the active components of a removable appliance
T/Z Springs (buccal movement) Finger Springs (mesio-distal movement) Labial bow (reduces OJ) Expansion screw (expands maxillary width) Biteplane (reduces OB)
Name the retentive components of a removable appliance
Adams clasps
Cribs
Arrowheads
List the 6 Andrews Keys
Correct molar relationship Correct crown angulation (Tip) Correct crown inclination (torque) No rotations No spaces Curve of spee
What is abfraction?
Non carious tooth loss, occurs around gingival margin, can occur from traumatic force caused by bruxism
Where are the following supernumary teeth located?
Mesiondens
Distomolar
Paramolar
Mesiondens - Maxillary central & incisors (most common supernumary)
Distomolar - Distal to 3rd molar
Paramolar - buccal or lingual to molar
What is hylanisation?
Too much force is used, roots start to resorb, tooth mobility, movement stops
What is the ‘leeway space’?
Difference in space in the arch when the D’s & E’s exfoliate and the 4’s & 5’s erupt.
