AP discrepancies

Question 1

Class 2 malocc

% gen pop/US pts

Answer 1

The class II malocclusion is among the most common developmental anomalies with a prevalence of around 30% in the general population
* Affecting 33% of all orthodontic patients in the U.S.A.

Question 2

categories class 2

Answer 2

Maxillary excess
* Mandibular deficiency
* Combination

Question 3

etiology of class 2

Answer 3

The etiology may be of skeletal or dental origin

Question 4

most frequent problem seen in ortho clinics

Answer 4

class 2

Question 5

The etiology of class II malocclusion has been linked to?

Answer 5

The etiology of class II malocclusion has been linked to hereditary and environmental factors

Question 6

Diagnosis & Clinical Features of class 2:
* Class II malocclusions may be identified by?
* Class II malocclusions may reflect:

Answer 6

• Class II malocclusions may be identified by precise clinical evaluation
• Class II malocclusions may reflect:
• Maxilla-Mandible disharmony with underdevelopment of mandibular growth
• Dental disharmony (Angle classification)
• Combination

Question 7

Answer 7

class 2

Question 8

Diagnosis & Clinical Features of class 2
* Maxillary first molar position?
* Two different types of Class II malocclusions?

Answer 8

• Maxillary first molar in a mesial position in relation to the
  mandibular first molar (distocclusion, lower M to the D)
• • Two different types of Class II malocclusions
• Class II Divivion1
• • Class II Division 2

Question 9

class 2 div 1

• profile,
• mandible
• facial height,
• overjet

Answer 9

• Convex profile,
• mandibular retrognathism,
• variable facial height,
• increased overjet (proclined maxillary incisors)

Question 10

class 2 div 2

• profile,
• lower facial height,
• overjet,
• overbite,
• maxillary central incisors,
• maxillary lateral incisors

Answer 10

• straight to convex profile,
• decreased lower facial height,
• normal overjet,
• deep overbite,
• retroclined maxillary central incisors,
• labially inclined maxillary lateral incisors

Question 11

Class II Division 1
* In severe (skeletal) class II division 1, the lips?
* Proclination of?
* Increased ?
* maxillary arch?

Answer 11

• In severe (skeletal) class II division 1, the lips
  are usually incompetent
• Proclination of upper incisors
• Increased overjet
• Narrow and tapered upper maxillary arch

Question 12

Class II Division 2
* Vertical dimension is usually?
* Dental crowding is created by?
* overbite?

Answer 12

• Vertical dimension is usually decreased in comparison with Class II division 1
• Dental crowding is created by retroclination of the maxillary central incisors
• Deep overbite caused by the over eruption of the maxillary central incisors and lower incisors

Question 13

Skeletal Class II
* Skeletal class II malocclusion components may be classified by:

Answer 13

• Maxillomandibular relationship: Mandibular retrognathism, midface protrusion or both
• Vertical discrepancy: Anterior upper face height often greater than normal, and steep occlusal plane

Question 14

tx of skeletal class 2

• Treatment strategies of class II
  malocclusion are categorized based on:

Answer 14

categorized based on: Growing and Non‐growing status of patients.
* Growing patients: Ideally, treatment of Class II malocclusions should focus first on improving the skeletal discrepancy
* Using Functional Appliances while the individual is still growing. (Growth Modification)

Question 15

class 2 skeletal in adults tx

Answer 15

In adults, repositioning of the maxilla and mandible can be achieved with:
* Orthognathic surgery: Adjusting the position of both in relation to the cranial base in the three dimensions and improving overall facial esthetics.
* Dentoalveolar compensation alone: Camouflage dental treatment

Question 16

class 2 malocc tx flowchart

Answer 16

Question 17

Removable Functional
Appliances:
* Both removable functional appliances and headgear therapy depend on?
* Among the different removable appliances, what is used more often?
how does it work?

Answer 17

• Both removable functional appliances and headgear therapy depend on the
  cooperation of the patients.
• Among the different removable appliances, Twin‐block is used more often, which can efficiently promote mandibular growth/enhance dif growth, restrict further forward growth of the maxilla, and improve skeletal relationships in growing skeletal class II individuals with mandibular retrusion.

Question 18

Fixed Functional Appliances
* The key differences between removable and fixed appliances are?
* Dental changes with fixed appliances compared t skeletal changes w removal app?

Answer 18

• The key differences between removable and fixed appliances are different working hours (intermittent vs. continuous), and also optimal treatment timing (before puberty growth vs. at or after puberty spurt) and direction of further growth.
• Dental changes with fixed appliances including mesial movement of lower molars and proclination of lower incisors were more significant than skeletal changes when compared to removable appliance

Question 19

Late Management Class II malocclusions
* In contrast to growing patients?
* Depending on the severity of malocclusion:
* Orthognathic surgical modalities may be used to ?

Answer 19

• In contrast to growing patients, limited range of treatment modalities can be used for adult cases with class II skeletal and dental malocclusions.
• Depending on the severity of malocclusion: Class II elastics, compensatory extractions (maxillary premolars and/or mandibular premolars)
• Orthognathic surgical modalities may be used to alleviate the functional and esthetic problems associated with this type of malocclusion.

Question 20

Severe Class II malocclusions tx
* Orthognathic surgery:
* The proper presurgical requirement?
* Although orthognathic surgery could be an efficient treatment modality in severe class II patients, what prevents this

Answer 20

• Orthognathic surgery:
  Mandibular advancement with or without maxillary impaction (
  Class II openbite)
• The proper presurgical orthodontic tooth movements and alignment of arches are essential to maximize the amount of discrepancy correction during surgery.
• Although orthognathic surgery could be an efficient treatment modality in severe class II patients, both the cost of the surgery and the fear of undergoing surgery normally prevent patients from
  choosing this treatment option.

Question 21

what can be seen when class2 div1 is moved to class 1?

Answer 21

transverse discrepancy: due to narrow tapered mx arch

Question 22

how do twin blocks work?

Answer 22

pushes man forward when pt bites

Question 23

how does a herbst device work?

Answer 23

fixed app, pushes man forward when pt bites

Question 24

Severe Class II malocclusions
* Orthognathic surgery:
* The proper presurgical tasks?
* Although orthognathic surgery could be an efficient treatment
modality in severe class II patients, what stops this?

Answer 24

• Orthognathic surgery: Mandibular advancement with or without maxillary impaction (
  Class II openbite)
• The proper presurgical orthodontic tooth movements and alignment of arches are essential to maximize the amount of discrepancy correction during surgery.
• Although orthognathic surgery could be an efficient treatment modality in severe class II patients, both the cost of the surgery and the fear of undergoing surgery normally prevent patients from choosing this treatment option.

Question 25

difficulty of tx class 3

Answer 25

most diff and complex

Question 26

skeletal class 3 characterized by:

Answer 26

* Mandibular prognathism * Maxillary deficiency * Some combination of these two feature

Question 27

CLass 3 prev in dif ethnicities

Answer 27

* The prevalence in Caucasians ranges between 1% and 4%. * A high prevalence has been reported in Asians 20% of Japanese .

Question 28

class 3 etiologies? more than half reported to be from? precise %?

Answer 28

* Like other types of malocclusions, the etiology of class III malocclusion has been linked to hereditary and environmental factors . * More than half of all skeletal Class III malocclusions are reported to result from maxillary deficiency. * More precisely, the incidence of Class III malocclusions suffering from maxillary deficiency was reported to be 65–67%

Question 29

Extraoral features of class 3 * profile? * Anterior facial * Prominent third?

Answer 29

Extraoral features : * Concave profile. * Anterior facial divergence. * Prominent lower third of face/chin

Question 30

introral features of class 3 * molar and canine relationship. *upper arch. * overjet. * Crowding?

Answer 30

* Class III molar and canine relationship. * Narrow upper arch. * Decreased or reverse overjet. * Crowding in upper arch.

Question 31

Etiology of Class III * The etiology is associated with? * The etiological factors of this malocclusion have been classified into two groups:

Answer 31

Etiology of Class III * The etiology is associated with environmental and genetic factors. * The etiological factors of this malocclusion have been classified into three groups: 1. Skeletal: Hypoplastic maxilla. Hyperplastic mandible. Combination 2. Dental: Anterior crossbite of functional origin

Question 32

Functional/pseudo Class III characterized by:

Answer 32

* Anterior crossbite * Due to a forward functional displacement of the mandible * CR-CO Shift * Not a true Class III malocclusion if corrected early

Question 33

Functional Class III Treatment * In most cases, what is the main etiological factor of a pseudo-Class III malocclusion. * Correction of ?

Answer 33

* In most cases, retroclined maxillary incisors is the main etiological factor of a pseudo-Class III malocclusion. * Correction of the anterior crossbite must be carried out as soon as it is detected to increase the orthopedic effects, thereby increasing the long-term stability of the treatment results.

Question 34

Functional Anterior Crossbite: Centric occlusion to Centric relation occ end to end?

Answer 34

Manipulate the condyles in their physiologic rest position. If the occlusion is end to end it is probable that the crossbite is functional

Question 35

class 3 malocc tx flowchart

Answer 35

Question 36

Treatment Growing Patients: Maxillary Expansion-Protraction face mask Goals:

Answer 36

Goals: Expand upper jaw to accommodate the lower dentition . Apply traction to the maxilla to reposition it more anteriorly. Slow down growth of mandible

Question 37

facemask mechanism and age restriction

Answer 37

* A facemask attached to a maxillary expansion appliance to promote anterior maxilla repositioning by inducing growth at the maxillary sutures. * The chance of true skeletal change appears to decline beyond age 8, and the chance of clinical success declines at age 10 to 11.

Question 38

how long are facemasks used

Answer 38

12h/day for 1 yr

Question 39

Late Management Class III malocclusions * The principles involved in the comprehensive treatment of Class III dentoalveolar malocclusions are: * Relief of ? * Level and align? * Increase? * Compensation by?

Answer 39

* Relief of crowding * Level and align arches * Increase overbite and overjet * Compensation by over proclination of upper incisors and retroclination of lower incisors

Question 40

Late Management Class III malocclusions * In cases with moderate or severe Class III anteroposterior skeletal discrepancies, a combination of? * Usually, what is done? * More rarely a?

Answer 40

* In cases with moderate or severe Class III anteroposterior skeletal discrepancies, a combination of orthodontic treatment and orthognathic surgery at the completion of skeletal growth (earlier in females than males) will be required to create an acceptable and stable Class I occlusion. * Usually, an anterior and vertical maxillary repositioning is done * More rarely a mandibular set back

Question 41

Late Management Class III malocclusions * Presurgical orthodontic treatment usually involves? * what is often required after surgery to finish and detail the occlusion.

Answer 41

* Presurgical orthodontic treatment usually involves to align themaxillary and mandibular arches, in order that they will co-ordinate when their respective skeletal bases have been surgically repositioned. (Decompensation) * A short period of orthodontic treatment (ideally less than 6 months) is often required after surgery to finish and detail the occlusion.